Date   

Re: Transmit AX.25

Siegfried Jackstien
 

wrong ... for tx into console you can use a few ways

via virtual comport ... (depends what packet software you use)

or with using vox (that works for sure)

then sdr console will switch tx on (and also pluto or lime will go into tx mode)

tx from hardware sdr to pa?? pluto can have a ptt relais installed ... lime has gpo pins that support ptt out ... and sdr console can control usb relais ... so also a few options to solve ptt towards power amp (and a koax relais)

now where is the problem??

a few options for ptt in ... and ptt out

greetz sigi dg9bfc

Am 26.02.2022 um 21:55 schrieb Douglas Pervine:

Easier said than done.

The problem is keying PTT.  SDR software doesn't have a way to PTT transmit on and off.
and/or
SDR devices (i.e. LimeSDR Mini / Adalm-Pluto) can't accept a PTT.

Transmit is a constant right now.  (VOX doesn't work at all.)


Re: Transmit AX.25

Simon Brown
 

VOX should work – add a screenshot of the whole console.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Douglas Pervine
Sent: 26 February 2022 20:55
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Transmit AX.25

 

Easier said than done.

The problem is keying PTT.  SDR software doesn't have a way to PTT transmit on and off.
and/or
SDR devices (i.e. LimeSDR Mini / Adalm-Pluto) can't accept a PTT.

Transmit is a constant right now.  (VOX doesn't work at all.)


--
- + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Re: Transmit AX.25

Douglas Pervine
 

Easier said than done.

The problem is keying PTT.  SDR software doesn't have a way to PTT transmit on and off.
and/or
SDR devices (i.e. LimeSDR Mini / Adalm-Pluto) can't accept a PTT.

Transmit is a constant right now.  (VOX doesn't work at all.)


Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Daniel Young
 

Hi Mark, exactly we have several new foundation licence holders and QTH of some club members S9+ noise.
Finances may mean a Frankenstein rig for some. The Dow key will take 100watts?

I've been playing with an Andrus SDR MK1.5  modified and a Pluto hacked to duel core and 70mhz-6ghz 

I'm very much interested in the HPSDR etc.

Regards
Dan

On Sat, 26 Feb 2022, 14:16 Mark Cayton, <oldjackbob@...> wrote:
Daniel,

My first ham station consisted of an 897 for transmit, a FUNcube Pro Plus dongle and SDRC (running on a 40 inch 4k screen) for receive, a single G5RV shared between the 897 and FCPP, and a Dow-Key coax relay that switched the antenna between the 897 for transmit and the FCPP for receive.

That setup worked beautifully. The 12-volt Dow-Key unit was a fail-safe unit (break-before-make so there was never any risk of pumping any transmit power into the Funcube dongle) triggered by the amp relay circuit on the 897. OmniRig ran the interface between the 897 and SDRC.

I really loved that setup, it worked so well that I never even bothered to learn how to use the receiver on the 897, lol.

Mark K1LSB


Re: IC-7300 composite noise

Siegfried Jackstien
 

the si5323 has some high phase noise ... not?!?

dg9bfc sigi

Am 25.02.2022 um 20:47 schrieb Larry Dodd:

Often the clock phase noise is the same whether run on an analog mains power supply or a DC battery. The total noise is inherent in the clock and other circuit design not its necessarily just the source of power. I run my station clock reference through a Silicon Labs Si5323 to clean up and stabilize the clock. 
Larry K4LED

On 2/25/2022 17:52:38, jdow <jdow@...> wrote:

On a hunch - run the radio on batteries. That this could be power supply noise modulating one of the stages or (horrors) the D/A converter's reference. (And I sort of wonder what the instrument's own phase noise is. Those numbers look a little too good. I'll check when I get up. It's bed time on my awfully skewed personal clock. Joanne Standard Time. The time zone changes UTC offset daily by as much as 6 hours. Insomnia is a way of life.)

{^_^}

On 20220225 06:59:57, Conrad, PA5Y wrote:

The Keysite picture was showing the spurs from a Hermes at 28.4 MHz with a 192kHz sample rate using the V1 firmware. it has nothing to do with the IC7300.

 

I have spare time now so I will repost the image of the IC-7300.

 

IC-7300 is at 30W output on 28.2 MHz with offsets from 10Hz to 1MHz, Blue trace is PN, Black trace is AM noise, Green trace is composite noise. This uses the FSWP which can measure AM noise and PN simultaneously.

 

Then I will go away for a while.

 

 

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Looking at the Keysight picture you posted it's hard to tell the characteristics of the peaks that appear beside the (was it?) 28.4 MHz signal. (The screen notation of 390 kHz is confusing. That is the marker's offset?)

It appears like the 7300 is using a digital frequency synthesizer with way too few bits to make a good signal. If I got a rig that bad I think I'd have some stern words with ICOM about it. While it might be marginally legal it is unethical to sell something that bad. (And at 100W I thought the limit was -70 dB in the US.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 



Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Siegfried Jackstien
 

or "spread the elbows" a bit to have some room ... they splatter as wide as a barn door that nobody may sit next to them (and splatter in their passband)

dg9bfc sigi

Am 26.02.2022 um 19:35 schrieb Robert Lorenzini:

You don't know anything about contesting. :-) They want the dirtiest signal possible
to keep the enemy at arms length.

Bob - wd6dod

On 2/25/2022 10:22 PM, jdow wrote:
I am not sure why contesters at multi-op stations don't use rigs with the best TX signals they can get. With adequate antenna separation you can place more operators on the same band. It's a serious points increase opportunity. (But, I don't do contests so what do I know? I just go back to an old and maybe current military goal to have two radios on separate antennas on a jeep and use them as ad hoc repeaters. And, yes, jeep. It goes back that far.)

{^_^}

On 20220225 11:38:38, Larry Dodd wrote:
Right on.  Not many amateur radio operators or radio enthusiasts are in a position to pay >$10k for a receiver or transceiver. In reality they don't "need" that level of precision even though its desired. Far surpasses the minimum requirements of the FCC rules. Yes its great to pursue and more power to those that are capable of doing so. Pure Signal is a great achievement.  Can't imagine the dollars spent on high end microphones and audio equipment that are far beyond what is necessary for voice communications. The ultimate is that 24k Gold Plated CW key.
Larry K4LED


On 2/25/2022 18:06:02, jdow <jdow@...> wrote:

There is an economics pressure here. Who is going to be the first company to give up being price competitive in a small commodity market and will that company survive the hit to its bottom line? A LOT of pressure from actual customers will be required to advance the commodity transceiver state of the art.

(And this thread is about the Hermes with it as a proof of concept for more general improvements - and their failures. It's been interesting.)

{o.o}

On 20220225 06:50:24, Conrad, PA5Y wrote:

Hello I never meant to come across as acrimonious, just insistent.

 

The plot is from a Rohde and Swartz FSUP signal source analyser in this case.

https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSUP_bro_en.pdf

 

The LO I used is from Kuhne electronics and is known as the XO1, it was intended as a 116MHz LO for use with 144 MHz transverters. It is not a custom product. It is simple Xtal oscillator with a narrow band PLL. The plot shows its performance when locked to a Leo Bodnar GPSDO at 10MHz.

 

It is normalised to 1Hz so in an SSB BW you can add 68dB to this plot assuming 2400Hz BW for SSB. I do not agree that this performance levels are only obtainable by special equipment. In fact older equipment like the IC-202 used to fair better. New equipment is making a pigs ear of this and transmitters are getting worse. A K3S and a transverter is all you need, or indeed a FDM Duo, Hermes, Flex or ANAN SDR.

 

These radios are all capable of meeting the code of conduct which in practice does have a positive effect. Not perfect but its existence is useful.

 

Now that we have such excellent receivers maybe we should pay attention to the TX chain?

 

This thread was about the Hermes, I apologise for hijacking it.

 

Regards

 

Conrad

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:30
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Um, I am not sure I understand that picture. That is the analyzer's specification or something very custom you have put together? I'm answering both emails here.

If that is the noise level you are insisting everybody meet I suspect you are going to be a very frustrated gentleman for the rest of your life. (Some old rigs never die. They simply make more noise.) The IC7300 might be capable of being tamed with a reference oscillator replacement. But I bet more bits in the D/A are required for that design than exist in reasonably priced D/A converters. Regardless "state of the art" only appears in hand tweaked radios or VERY expensive military or scientific equipment where there is a perceived need. (And codes of conduct are not worth the bits they fill on an exabyte storage array. Cats and humans cannot be herded.)

Even if 7300s are not "clean" as you would have it are they cleaner than their peers on the commercial market? From your complaints I suspect they are not. But it is a point worth asking. I ignored the argument until it got acrimonious.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 





Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Robert Lorenzini
 

You don't know anything about contesting. :-) They want the dirtiest signal possible
to keep the enemy at arms length.

Bob - wd6dod

On 2/25/2022 10:22 PM, jdow wrote:

I am not sure why contesters at multi-op stations don't use rigs with the best TX signals they can get. With adequate antenna separation you can place more operators on the same band. It's a serious points increase opportunity. (But, I don't do contests so what do I know? I just go back to an old and maybe current military goal to have two radios on separate antennas on a jeep and use them as ad hoc repeaters. And, yes, jeep. It goes back that far.)

{^_^}

On 20220225 11:38:38, Larry Dodd wrote:
Right on.  Not many amateur radio operators or radio enthusiasts are in a position to pay >$10k for a receiver or transceiver. In reality they don't "need" that level of precision even though its desired. Far surpasses the minimum requirements of the FCC rules. Yes its great to pursue and more power to those that are capable of doing so. Pure Signal is a great achievement.  Can't imagine the dollars spent on high end microphones and audio equipment that are far beyond what is necessary for voice communications. The ultimate is that 24k Gold Plated CW key.
Larry K4LED


On 2/25/2022 18:06:02, jdow <jdow@...> wrote:

There is an economics pressure here. Who is going to be the first company to give up being price competitive in a small commodity market and will that company survive the hit to its bottom line? A LOT of pressure from actual customers will be required to advance the commodity transceiver state of the art.

(And this thread is about the Hermes with it as a proof of concept for more general improvements - and their failures. It's been interesting.)

{o.o}

On 20220225 06:50:24, Conrad, PA5Y wrote:

Hello I never meant to come across as acrimonious, just insistent.

 

The plot is from a Rohde and Swartz FSUP signal source analyser in this case.

https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSUP_bro_en.pdf

 

The LO I used is from Kuhne electronics and is known as the XO1, it was intended as a 116MHz LO for use with 144 MHz transverters. It is not a custom product. It is simple Xtal oscillator with a narrow band PLL. The plot shows its performance when locked to a Leo Bodnar GPSDO at 10MHz.

 

It is normalised to 1Hz so in an SSB BW you can add 68dB to this plot assuming 2400Hz BW for SSB. I do not agree that this performance levels are only obtainable by special equipment. In fact older equipment like the IC-202 used to fair better. New equipment is making a pigs ear of this and transmitters are getting worse. A K3S and a transverter is all you need, or indeed a FDM Duo, Hermes, Flex or ANAN SDR.

 

These radios are all capable of meeting the code of conduct which in practice does have a positive effect. Not perfect but its existence is useful.

 

Now that we have such excellent receivers maybe we should pay attention to the TX chain?

 

This thread was about the Hermes, I apologise for hijacking it.

 

Regards

 

Conrad

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:30
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Um, I am not sure I understand that picture. That is the analyzer's specification or something very custom you have put together? I'm answering both emails here.

If that is the noise level you are insisting everybody meet I suspect you are going to be a very frustrated gentleman for the rest of your life. (Some old rigs never die. They simply make more noise.) The IC7300 might be capable of being tamed with a reference oscillator replacement. But I bet more bits in the D/A are required for that design than exist in reasonably priced D/A converters. Regardless "state of the art" only appears in hand tweaked radios or VERY expensive military or scientific equipment where there is a perceived need. (And codes of conduct are not worth the bits they fill on an exabyte storage array. Cats and humans cannot be herded.)

Even if 7300s are not "clean" as you would have it are they cleaner than their peers on the commercial market? From your complaints I suspect they are not. But it is a point worth asking. I ignored the argument until it got acrimonious.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 





Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Mark Cayton
 

Daniel,

My first ham station consisted of an 897 for transmit, a FUNcube Pro Plus dongle and SDRC (running on a 40 inch 4k screen) for receive, a single G5RV shared between the 897 and FCPP, and a Dow-Key coax relay that switched the antenna between the 897 for transmit and the FCPP for receive.

That setup worked beautifully. The 12-volt Dow-Key unit was a fail-safe unit (break-before-make so there was never any risk of pumping any transmit power into the Funcube dongle) triggered by the amp relay circuit on the 897. OmniRig ran the interface between the 897 and SDRC.

I really loved that setup, it worked so well that I never even bothered to learn how to use the receiver on the 897, lol.

Mark K1LSB


Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Daniel Young
 

The 7300 is a relatively affordable radio,
Personally I use an sdr switch box and cat rig control with local SDR or even websdr.
Different strokes for different folks.
Omnirig and an sdr switch and receiver may be a way of modernising hardware people use.

The second point is certain conditions as pointed out traditional reciever may have better unwanted signal rejection.

I even have an 847 with IF tap  as hybrid sdr

On Fri, 25 Feb 2022, 18:55 Conrad, PA5Y, <g0ruz@...> wrote:

Wooooaahhh hold on. I most certainly am not a PS hater. Its great! You really have got the wrong end of the stick. The ANAN-7000 is a fine radio and is definitely capable of better performance with PS than either of my beloved radios. However, for me, driving transverters I have no need for Pure signal.

 

I have no idea where ANY of that came from.

 

I do dislike the IC-7300s because I have loads of the bloody things nearby on 6m and it is not clean. No way. However, when things were properly described I accept that it is good enough on the low bands where the noise floor is MUCH higher.

 

The ANAN-7000 even without PS knocks spots off it.

 

So, we agree.

 

73

 

Conrad PA5Y

 

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 25 February 2022 19:42
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Conrad,

And it's not our fault that we're all talking apples (HF) and you're talking oranges (950 MHZ!) lol.

It's clear you're a PS hater, you've made that abundantly clear in numerous posts in this thread, when in reality there's nothing to hate about PS. It brings a quantum improvement (at least 20 dB) in signal cleanness to the table, for free! The algorithm is open source and can be implemented in software and minimal circuitry. You just can't stomach the fact that your beloved K3S and 890S will never hold a candle to any ANAN (or even a lowly IC-7300) for signal purity.

I'm done with this topic.

Mark


Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Conrad, PA5Y
 

Excellent!

 

Conrad

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 25 February 2022 20:37
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Getting PS working is a major goal for Q2. I actually have a lot of code in place…

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Conrad, PA5Y
Sent: 25 February 2022 19:35
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

No problem Mark. Really!

 

I also got uppity about the IC7300 😊

 

I think that we would both like PS to be available on SDRC, but that is far from trivial and a lot to ask of Simon.

 

73

 

Conrad

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 25 February 2022 20:20
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Conrad,

My apologies for my untoward attitude, you're a good man. This whole discussion has just got me really worked up for some reason so I need to back away from the thread.

Best regards,

Mark  K1LSB


--

- + - + -

Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.


Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

Larry Dodd
 

Glad to be of service!  I experience that same phenomena from time to time. Especially with flashes of nostalgic thoughts. 
Larry K4LED 

------------
K4LED Links:
https://101science.com

https://www.101science.com/radiojove.html


http://youtube.com/channel/UCtawz3MnMBwjz9ShhSC0ygQ/live


On Feb 26, 2022, at 1:27 AM, jdow <jdow@...> wrote:

 I have a SICK SICK mind. You made a broad statement and my head wondered if the 24 caret Gold Plated CW Key was all that absurd. I experienced my typical blur of possibilities fly through my mind and a card dropped out. It actually could be a benefit if the plating was thick enough. Gold is soft. The thick plating might stop some key bounce. Of course, I suspect lead would work as well for the same reason. I really wonder if that might be some form of a good idea.

(I can't help it. My mind does this to me and I can't stop it. I can't even pull up the failed ideas in my memory. It's frustrating and in a way fun.)

Thanks for bumping my mind this way. It's a fun trip when it happens. You made my day.

{O.O}

On 20220225 11:38:38, Larry Dodd wrote:
Right on.  Not many amateur radio operators or radio enthusiasts are in a position to pay >$10k for a receiver or transceiver. In reality they don't "need" that level of precision even though its desired. Far surpasses the minimum requirements of the FCC rules. Yes its great to pursue and more power to those that are capable of doing so. Pure Signal is a great achievement.  Can't imagine the dollars spent on high end microphones and audio equipment that are far beyond what is necessary for voice communications. The ultimate is that 24k Gold Plated CW key.
Larry K4LED


On 2/25/2022 18:06:02, jdow <jdow@...> wrote:

There is an economics pressure here. Who is going to be the first company to give up being price competitive in a small commodity market and will that company survive the hit to its bottom line? A LOT of pressure from actual customers will be required to advance the commodity transceiver state of the art.

(And this thread is about the Hermes with it as a proof of concept for more general improvements - and their failures. It's been interesting.)

{o.o}

On 20220225 06:50:24, Conrad, PA5Y wrote:

Hello I never meant to come across as acrimonious, just insistent.

 

The plot is from a Rohde and Swartz FSUP signal source analyser in this case.

https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSUP_bro_en.pdf

 

The LO I used is from Kuhne electronics and is known as the XO1, it was intended as a 116MHz LO for use with 144 MHz transverters. It is not a custom product. It is simple Xtal oscillator with a narrow band PLL. The plot shows its performance when locked to a Leo Bodnar GPSDO at 10MHz.

 

It is normalised to 1Hz so in an SSB BW you can add 68dB to this plot assuming 2400Hz BW for SSB. I do not agree that this performance levels are only obtainable by special equipment. In fact older equipment like the IC-202 used to fair better. New equipment is making a pigs ear of this and transmitters are getting worse. A K3S and a transverter is all you need, or indeed a FDM Duo, Hermes, Flex or ANAN SDR.

 

These radios are all capable of meeting the code of conduct which in practice does have a positive effect. Not perfect but its existence is useful.

 

Now that we have such excellent receivers maybe we should pay attention to the TX chain?

 

This thread was about the Hermes, I apologise for hijacking it.

 

Regards

 

Conrad

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:30
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Um, I am not sure I understand that picture. That is the analyzer's specification or something very custom you have put together? I'm answering both emails here.

If that is the noise level you are insisting everybody meet I suspect you are going to be a very frustrated gentleman for the rest of your life. (Some old rigs never die. They simply make more noise.) The IC7300 might be capable of being tamed with a reference oscillator replacement. But I bet more bits in the D/A are required for that design than exist in reasonably priced D/A converters. Regardless "state of the art" only appears in hand tweaked radios or VERY expensive military or scientific equipment where there is a perceived need. (And codes of conduct are not worth the bits they fill on an exabyte storage array. Cats and humans cannot be herded.)

Even if 7300s are not "clean" as you would have it are they cleaner than their peers on the commercial market? From your complaints I suspect they are not. But it is a point worth asking. I ignored the argument until it got acrimonious.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 




Re: IC-7300 composite noise

jdow
 

It may be an internal powersupply that takes 13.8 VDC down to 5 VDC. In that case there is no help for it without significant surgery.

{^_^}

On 20220225 11:49:05, Conrad, PA5Y wrote:

I thought the same and so indeed I tried batteries with the same result. Also, I tried a variety of lab grade PSUs, prior to trying batteries. Always the same. At this point I gave up and sold my IC-7300. It is good value for money but not suitable for 10m and above if used with an amplifier.

 

Regards

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 18:52
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] IC-7300 composite noise

 

On a hunch - run the radio on batteries. That this could be power supply noise modulating one of the stages or (horrors) the D/A converter's reference. (And I sort of wonder what the instrument's own phase noise is. Those numbers look a little too good. I'll check when I get up. It's bed time on my awfully skewed personal clock. Joanne Standard Time. The time zone changes UTC offset daily by as much as 6 hours. Insomnia is a way of life.)

{^_^}

On 20220225 06:59:57, Conrad, PA5Y wrote:

The Keysite picture was showing the spurs from a Hermes at 28.4 MHz with a 192kHz sample rate using the V1 firmware. it has nothing to do with the IC7300.

 

I have spare time now so I will repost the image of the IC-7300.

 

IC-7300 is at 30W output on 28.2 MHz with offsets from 10Hz to 1MHz, Blue trace is PN, Black trace is AM noise, Green trace is composite noise. This uses the FSWP which can measure AM noise and PN simultaneously.

 

Then I will go away for a while.

 

 

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:39
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Looking at the Keysight picture you posted it's hard to tell the characteristics of the peaks that appear beside the (was it?) 28.4 MHz signal. (The screen notation of 390 kHz is confusing. That is the marker's offset?)

It appears like the 7300 is using a digital frequency synthesizer with way too few bits to make a good signal. If I got a rig that bad I think I'd have some stern words with ICOM about it. While it might be marginally legal it is unethical to sell something that bad. (And at 100W I thought the limit was -70 dB in the US.

{^_^}


On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}



On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}




On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark





 

 

 

 



Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

jdow
 

I have a SICK SICK mind. You made a broad statement and my head wondered if the 24 caret Gold Plated CW Key was all that absurd. I experienced my typical blur of possibilities fly through my mind and a card dropped out. It actually could be a benefit if the plating was thick enough. Gold is soft. The thick plating might stop some key bounce. Of course, I suspect lead would work as well for the same reason. I really wonder if that might be some form of a good idea.

(I can't help it. My mind does this to me and I can't stop it. I can't even pull up the failed ideas in my memory. It's frustrating and in a way fun.)

Thanks for bumping my mind this way. It's a fun trip when it happens. You made my day.

{O.O}

On 20220225 11:38:38, Larry Dodd wrote:

Right on.  Not many amateur radio operators or radio enthusiasts are in a position to pay >$10k for a receiver or transceiver. In reality they don't "need" that level of precision even though its desired. Far surpasses the minimum requirements of the FCC rules. Yes its great to pursue and more power to those that are capable of doing so. Pure Signal is a great achievement.  Can't imagine the dollars spent on high end microphones and audio equipment that are far beyond what is necessary for voice communications. The ultimate is that 24k Gold Plated CW key.
Larry K4LED


On 2/25/2022 18:06:02, jdow <jdow@...> wrote:

There is an economics pressure here. Who is going to be the first company to give up being price competitive in a small commodity market and will that company survive the hit to its bottom line? A LOT of pressure from actual customers will be required to advance the commodity transceiver state of the art.

(And this thread is about the Hermes with it as a proof of concept for more general improvements - and their failures. It's been interesting.)

{o.o}

On 20220225 06:50:24, Conrad, PA5Y wrote:

Hello I never meant to come across as acrimonious, just insistent.

 

The plot is from a Rohde and Swartz FSUP signal source analyser in this case.

https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSUP_bro_en.pdf

 

The LO I used is from Kuhne electronics and is known as the XO1, it was intended as a 116MHz LO for use with 144 MHz transverters. It is not a custom product. It is simple Xtal oscillator with a narrow band PLL. The plot shows its performance when locked to a Leo Bodnar GPSDO at 10MHz.

 

It is normalised to 1Hz so in an SSB BW you can add 68dB to this plot assuming 2400Hz BW for SSB. I do not agree that this performance levels are only obtainable by special equipment. In fact older equipment like the IC-202 used to fair better. New equipment is making a pigs ear of this and transmitters are getting worse. A K3S and a transverter is all you need, or indeed a FDM Duo, Hermes, Flex or ANAN SDR.

 

These radios are all capable of meeting the code of conduct which in practice does have a positive effect. Not perfect but its existence is useful.

 

Now that we have such excellent receivers maybe we should pay attention to the TX chain?

 

This thread was about the Hermes, I apologise for hijacking it.

 

Regards

 

Conrad

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:30
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Um, I am not sure I understand that picture. That is the analyzer's specification or something very custom you have put together? I'm answering both emails here.

If that is the noise level you are insisting everybody meet I suspect you are going to be a very frustrated gentleman for the rest of your life. (Some old rigs never die. They simply make more noise.) The IC7300 might be capable of being tamed with a reference oscillator replacement. But I bet more bits in the D/A are required for that design than exist in reasonably priced D/A converters. Regardless "state of the art" only appears in hand tweaked radios or VERY expensive military or scientific equipment where there is a perceived need. (And codes of conduct are not worth the bits they fill on an exabyte storage array. Cats and humans cannot be herded.)

Even if 7300s are not "clean" as you would have it are they cleaner than their peers on the commercial market? From your complaints I suspect they are not. But it is a point worth asking. I ignored the argument until it got acrimonious.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 




Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

jdow
 

I am not sure why contesters at multi-op stations don't use rigs with the best TX signals they can get. With adequate antenna separation you can place more operators on the same band. It's a serious points increase opportunity. (But, I don't do contests so what do I know? I just go back to an old and maybe current military goal to have two radios on separate antennas on a jeep and use them as ad hoc repeaters. And, yes, jeep. It goes back that far.)

{^_^}

On 20220225 11:38:38, Larry Dodd wrote:

Right on.  Not many amateur radio operators or radio enthusiasts are in a position to pay >$10k for a receiver or transceiver. In reality they don't "need" that level of precision even though its desired. Far surpasses the minimum requirements of the FCC rules. Yes its great to pursue and more power to those that are capable of doing so. Pure Signal is a great achievement.  Can't imagine the dollars spent on high end microphones and audio equipment that are far beyond what is necessary for voice communications. The ultimate is that 24k Gold Plated CW key.
Larry K4LED


On 2/25/2022 18:06:02, jdow <jdow@...> wrote:

There is an economics pressure here. Who is going to be the first company to give up being price competitive in a small commodity market and will that company survive the hit to its bottom line? A LOT of pressure from actual customers will be required to advance the commodity transceiver state of the art.

(And this thread is about the Hermes with it as a proof of concept for more general improvements - and their failures. It's been interesting.)

{o.o}

On 20220225 06:50:24, Conrad, PA5Y wrote:

Hello I never meant to come across as acrimonious, just insistent.

 

The plot is from a Rohde and Swartz FSUP signal source analyser in this case.

https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/dl_common_library/dl_brochures_and_datasheets/pdf_1/FSUP_bro_en.pdf

 

The LO I used is from Kuhne electronics and is known as the XO1, it was intended as a 116MHz LO for use with 144 MHz transverters. It is not a custom product. It is simple Xtal oscillator with a narrow band PLL. The plot shows its performance when locked to a Leo Bodnar GPSDO at 10MHz.

 

It is normalised to 1Hz so in an SSB BW you can add 68dB to this plot assuming 2400Hz BW for SSB. I do not agree that this performance levels are only obtainable by special equipment. In fact older equipment like the IC-202 used to fair better. New equipment is making a pigs ear of this and transmitters are getting worse. A K3S and a transverter is all you need, or indeed a FDM Duo, Hermes, Flex or ANAN SDR.

 

These radios are all capable of meeting the code of conduct which in practice does have a positive effect. Not perfect but its existence is useful.

 

Now that we have such excellent receivers maybe we should pay attention to the TX chain?

 

This thread was about the Hermes, I apologise for hijacking it.

 

Regards

 

Conrad

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 14:30
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Um, I am not sure I understand that picture. That is the analyzer's specification or something very custom you have put together? I'm answering both emails here.

If that is the noise level you are insisting everybody meet I suspect you are going to be a very frustrated gentleman for the rest of your life. (Some old rigs never die. They simply make more noise.) The IC7300 might be capable of being tamed with a reference oscillator replacement. But I bet more bits in the D/A are required for that design than exist in reasonably priced D/A converters. Regardless "state of the art" only appears in hand tweaked radios or VERY expensive military or scientific equipment where there is a perceived need. (And codes of conduct are not worth the bits they fill on an exabyte storage array. Cats and humans cannot be herded.)

Even if 7300s are not "clean" as you would have it are they cleaner than their peers on the commercial market? From your complaints I suspect they are not. But it is a point worth asking. I ignored the argument until it got acrimonious.

{^_^}

On 20220225 04:03:42, Conrad, PA5Y wrote:

Hi, no it is actually 5 different IC7300s tested by 3 different people, including Rob Sherwood. if you have time you can see the plots and some other data that I posted earlier just do a search. I’m in my lunch break or I would do it for you.

 

Yes my TX IS that good but it is easier for me because I use 0dBm transverter drives at 28Mhz and transverters with high quality Xtal local oscillators. The 0dBm from either my K3S or TS-890S is very good indeed. IMD3 from both is better than -50dBc.

 

On 144 MHz,  PN noise at 1kHz separation is -144dBc/Hz and close to 156dBc/Hz at 10kHz. This is with the LO PLL active, free running it is a little better. Composite noise is the same as in this case it is PN dominated. IM3 is -38dBc but more importantly the 7th and 9th orders are better than -80dBc. This is achieved by using tetrode finals on all bands.

 

432 and 1296 are of course worse as the LOs are multiplied from Xtals in the VHF region. However my TX is some 40dB better than an IC-9700 at 1.3GHz at 10kHz separation.

 

 

Only 50MHz is a little worse due to my TS-890S PA linearity but with the noise on 6m being higher it is acceptable. When I am on FT8 where linearity does not matter it is superb. But who cares we are all on the same ‘channel’.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 11:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I suspect your specification is still beyond the state of the art. Is your transmitter that good?

It sounds like the 7300 is cleaner than average close in but has some issues fairly far out. That is a little surprising. I wonder if the "IP+" technology is simply RF feedback to linearize the transmitter stages such as is seen in the old Collins kW SSB amplifiers. I can see that having an issue that depends on the charteristics of the feedback loop. But those are strange characteristics.

I take it the noise peaks are broadband, right? Do they depend on the transmit frequency in any way? It sounds very much like there is a defect in a specific radio near you. Is that the case or are hams measuring this in general? If this affects all the 7300s then the FPGA code will probably have to be reworked to fix the bug. I kinda wish I had one and a nice lab with lots of pertinent test equipment. I doubt Keysight and ICOM would set me up to do it. (It'd be better for them to set up a tiger team of their engineers with the equipment needed to suppress this possible bug.)

{^_^}


On 20220225 01:55:45, Conrad, PA5Y wrote:

By clean I mean - can I hear anything of sufficient magnitude to disturb the noise floor anywhere in band, and hence inhibit my ability to receive signals close to the noise floor. The noise floor in a semi-rural location on 28, 50 and 70MHz is not particularly low so I do not feel that this is unreasonable. The biggest problem with the IC7300 is the AM noise bump at 20kHz and 130kHz which is only 60dB down on the carrier when running at 30W on 28MHz. This power level is typical when driving an amplifier.  When modulated with an SSB signal this occupies a considerable amount of bandwidth.  The close in PN -s only -120dBc/Hz at 1kHz and  -130dBc/Hz at 10kHz. The composite noise is -115kHz at 10kHz, this is not what I would consider clean, even close in. The K3S( and a few others) is far better in this respect although the PA has quite poor linearity, especially on 6m.

 

The Hermes will do a much better job with any decent PA, even without pure signal. There are some spurs @ -65dBc which improve with a higher sample rate.  I have not checked these with the V2 firmware but I will do immediately I receive my Hermes from Apache.

 

I do not think that a transceiver at the IC-7300 price point has fixed pre-distortion. As you quite correctly say keeping it under control over temperature and voltage variation would be difficult. Also Icom would almost certainly have mentioned it in their advertising. What the IC7300 does well is manage audio overshoots by using a ‘look ahead’ algorithm. This is maybe where the impression of it having a clean TX comes from.

 

I think that the problem here is that so many transceivers are quite bad, so I can just about accept that the IC-7300 is less bad.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow via groups.io
Sent: 25 February 2022 10:27
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

OK, please refresh my mind what you mean by "clean". It certainly appears to be sending something much closer to pure signal concentrated within its intended bandwidth than most other transmitters. I also understand that it is not as good as it can be with full active predistortion. Both might generate increased noise at some significant separation from the intended signal frequency. I am not sure of the mechanism by which this would take place.

As an ornery critter there is nothing I would sit down and declare "clean" without a definition of "clean". I guess I am asking for your definition of the term or even of the term "clean enough".

{O.O}



On 20220225 01:13:11, Conrad, PA5Y wrote:

I KNOW for a fact that the IC7300 is not clean. Please provide me some evidence to the contrary. I have measurements with a R&S FSWP Signal analyser out to a 1MHz BW. You guys are looking in an SSB BW which is fine unless you happen to be 130kHz away, then you will hear plenty of splatter from the IC7300. I tested the IC-7300 as a result of hearing this on 50MHz. In other words the lab tests were driven by on air experience.

 

You are spreading misleading and incorrect information.

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 24 February 2022 23:12
To:
main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Wed, Feb 23, 2022 at 12:24 PM, Max wrote:

I just think if we follow good design and signal chain management that superb, clean signals can also be generated without the need for PS, that's all.

Max,

I disagree. My signal is my signature. Audio clarity is admittedly important but what matters most to me is a splatter-free signal, and in that regard nothing comes close to what PS can produce. As I stated earlier, even the best Class A amplifiers only have -40dB splatter. PS starts at -60db and often pushes -70dB. That means that PS reduces splatter to less than 1% (and at times only 1/10 of 1%) of what even the best traditional equipment can produce.

I also agree with Simon that the 7300 (and also the 7610 for that matter) produces an extremely sharp-edged signal with unarguably less splatter than is achievable with any other non-ANAN radio. It was explained to me by Ray N5LAX that the reason those radios are so clean splatter-wise is because ICOM embedded an algorithm into the firmware that functions very similarly to PS in the sense that it corrects for non-linearity in the PA, but it is a fixed-value (i.e., static) correction only, not a real-time self-adjusting correction value such as is employed by PS. NOTE: I have not been able to verify that info, but that is what was told to me over-the-air by Ray when I commented that I had no idea how the 7300 could produce such a clean, sharp-edged signal. So I'm repeating it here.

IMO it's unwise and short-sighted to summarily dismiss the game-changing value that PS brings to the hobby. Its benefits are so unarguable that I (and Rob Sherwood) often wonder why the big-name radios don't offer it as a standard feature. It's free, so utilize it for goodness sake!

73,

Mark




 

 

 




Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

jdow
 

Start as clean as  you can achieve then use PS if it is available. Both right. There is no single perfect correct way. Judiciously combine methods to make it better. (Wash hands, isolate from others as you can, and so forth. For an extra 10% maybe consider a mask.)

{^_-}

On 20220225 10:48:28, Conrad, PA5Y wrote:

Why so hostile? I am not trying to upset you. I made it perfectly clear that I was referring to the transverter port at 0dBm and that I only operate at 50MHz and above. I also said that the K3S PA was a disaster on 6m, it is and that is why I use the TS-890S. I also said that I cannot achieve these numbers on 50MHz but accept it because of the higher noise floor on 6m. My aim is to be a good radio neighbour and to try and get others to do the same. You are obviously one who cares about such things, so I think that we are on the same side here.  You did not bother to read my post because you have your own preconceptions. You just want agreement that PS on the ANAN-7000 is the cleanest possible signal available. I agree FWIW.

 

My measurements were on HF, 28MHz to be precise and appropriate for some potential users.

 

You made a statement that Class A amplifiers cannot be better than -40dBc 3rd orders, that is not correct. Analogue TV amplifiers are better than -50dBc and have been for years. They used to operate at 1kW or more. I just grabbed the first thing that I could find that was not heavily mathematical to show that class A amplifiers were not limited to the constraints you mentioned. A mini circuits datasheet seemed reasonable. It is harder to get good IMD at 950MHz.

 

I am not the only one who is going to use the Hermes with transverters, the thread was originally about Hermes. Simon said that it is better to start clean rather than use pure signal as a crutch. I agree.  The Hermes is a clean source.

 

Regards

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob via groups.io
Sent: 25 February 2022 18:48
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Fri, Feb 25, 2022 at 08:16 AM, Conrad, PA5Y wrote:

Look here at figure 3a, this is a Class A RF amplifier with no pre-distortion running at 2W per tone. The IM3 is -51.48dBc, this is at 950 MHz.

Conrad,

Good grief! This entire topic of your claims of wildly spectacular IMD3 numbers for your K3S and 890S has nothing to do with tiny amounts of power at 950 MHZ! The radios we're discussing (and the 7300 and the ANANs) operate at HF, not gigahertz!

And we've always been talking clearly in terms of final PA stage IMD3 levels, not some measurements taken at a transverter jack.

Show me the measured IMD3 from your K3S or 890S at the output of the PA finals at any power level over 5 watts, at any frequency the finals are designed to operate at, and show me it's anywhere near -50dB. Go ahead, I'll wait...

Mark



Re: Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

jdow
 

I was with you until that last snipe. It appears the 7300 MAY have a problem. If it has spurious at -3db from full output that are only 60 dB down removed 20 kHz and 100 kHz from the carrier that can wipe out portions of the band. I experienced this with somebody running PSK31 who had a subtle ground loop leading to some weak 120 Hz modulation on his (overdriven) PSK31 signal This made a portion of the spectrum within the PSK31 window at the time unusable for me. He lived in the same town so I got his signal at a high enough level for his spurious to be a problem.

{^_^}

On 20220225 10:42:22, oldjackbob@... wrote:

Conrad,

And it's not our fault that we're all talking apples (HF) and you're talking oranges (950 MHZ!) lol.

It's clear you're a PS hater, you've made that abundantly clear in numerous posts in this thread, when in reality there's nothing to hate about PS. It brings a quantum improvement (at least 20 dB) in signal cleanness to the table, for free! The algorithm is open source and can be implemented in software and minimal circuitry. You just can't stomach the fact that your beloved K3S and 890S will never hold a candle to any ANAN (or even a lowly IC-7300) for signal purity.

I'm done with this topic.

Mark



Re: Transmit AX.25

Siegfried Jackstien
 

if you can mary an sdr software together with a packet software via virtual audo cable then it is all you need

an sdr (hardware) like an rtl dngle .. or whatever

an sdr software (be it sdr console v3 ... or hdsdr .. or sdrsharp ... or...)

a packet software (be it direwolf or multipsk or ...)

virtual audio cable (to route the audio from sdr software to packet software)

hth

greetz sigi dg9bfc

Am 25.02.2022 um 23:41 schrieb Douglas Pervine:

I've been using SDR's for a couple years now, but I still consider myself a beginner.

I would like to use an SDR to transmit/receive AX.25.  Ideally, it would be great advantage to use Direwolf.  Is this possible?

Any assistance would be greatly appreciated. 


Transmit AX.25

Douglas Pervine
 

I've been using SDR's for a couple years now, but I still consider myself a beginner.

I would like to use an SDR to transmit/receive AX.25.  Ideally, it would be great advantage to use Direwolf.  Is this possible?

Any assistance would be greatly appreciated. 


Re: Open HPSDR Hermes Anan-10 Support

N2MS
 

I have the 16bit ANAN-10.

Thanks,

Mike N2MS

On 02/25/2022 3:10 PM Conrad, PA5Y <g0ruz@...> wrote:


Hi Mike if you have a 16bit ANAN-10, not 14bit 10E then you can find it here.

https://apache-labs.com/community/viewtopic.php?f=32&t=3310

73

Conrad PA5Y

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of N2MS via groups.io
Sent: 25 February 2022 21:05
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes Anan-10 Support

Simon,

Thanks. Would you know where I can find the protocol2 firmware?

Mike N2MS

On 02/25/2022 2:45 PM Simon Brown <simon@...> wrote:


Hi,

ANAN 10 already supported, not with PS though.

Simon Brown, G4ELI
https://www.sdr-radio.com

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of N2MS
Sent: 25 February 2022 19:44
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Open HPSDR Hermes Anan-10 Support

I've been following the discussion on support for the EP3C25 Transceiver Card.

Will SDRC support the ANAN-10? I assume I would have to install protocol2.

Mike N2M2







Re: Open HPSDR Hermes Anan-10 Support

Conrad, PA5Y
 

Hi Mike if you have a 16bit ANAN-10, not 14bit 10E then you can find it here.

https://apache-labs.com/community/viewtopic.php?f=32&t=3310

73

Conrad PA5Y

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of N2MS via groups.io
Sent: 25 February 2022 21:05
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes Anan-10 Support

Simon,

Thanks. Would you know where I can find the protocol2 firmware?

Mike N2MS

On 02/25/2022 2:45 PM Simon Brown <simon@...> wrote:


Hi,

ANAN 10 already supported, not with PS though.

Simon Brown, G4ELI
https://www.sdr-radio.com

-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of N2MS
Sent: 25 February 2022 19:44
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Open HPSDR Hermes Anan-10 Support

I've been following the discussion on support for the EP3C25 Transceiver Card.

Will SDRC support the ANAN-10? I assume I would have to install protocol2.

Mike N2M2

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