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

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}

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

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

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

Military contracts fall into the code names and acronyms to the point whole conversations seem to exclusively use acronyms without normal nouns, verbs, and stuff. I'm glad I am out of that now.
{o.o}

OK Simon.
I guess the filter tracking is generic to the HPSDR concept, let it be ANAN or Hermes.
Thanks for the info, good to know.
A name is just a name, is it an acronym for something? It might just be shorter to use a name rather than a full description.
The HPSDR crew seem to be very happy with naming the different parts. I have not been able to see any coupling between name and function on any of them.
Coming from the cellular base-station industry, I am fostered with acronyms for everything ;-) functions, products or projects, let it be that it looks like names and possible to pronounce :-)
Some of them needed a lot of fantasy and imagination to decode :-) and were created with the same amount of fantasy and imagination. LOF :-)
73 / Ingolf

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

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

Simon and Conrad.
It seems to me that you maybe are talking about two different parameters when it comes to a clean Tx-signal from the IC-7300.
I get that Simon is referring to splatter from the intended modulation.
I interpret that Conrad is looking at composite noise from a carrier.
I guess you are both correct.
If some kind of static Pre-Distortion is improving the the splatter levels from a SSB transmission it is very nice.
Still, the composite noise will be there in-between the modulation and also outside the modulation BW.
Splatter and composite noise will for sure have very different QRM characteristics on the band.
Can it be that the composite noise seen, is an artifact of the Pre-Distortion process?
Just a thought.....as I have never been deep diving into Pre-Distortion engineering. But usually there is a price to pay, if you are not very cautious with the details, when engineering a solution.
I am sure someone here is more into this and can explain.
73 / Ingolf, SM6FHZ

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

OK Simon.
I guess the filter tracking is generic to the HPSDR concept, let it be ANAN or Hermes.
Thanks for the info, good to know.
A name is just a name, is it an acronym for something? It might just be shorter to use a name rather than a full description.
The HPSDR crew seem to be very happy with naming the different parts. I have not been able to see any coupling between name and function on any of them.
Coming from the cellular base-station industry, I am fostered with acronyms for everything ;-) functions, products or projects, let it be that it looks like names and possible to pronounce :-)
Some of them needed a lot of fantasy and imagination to decode :-) and were created with the same amount of fantasy and imagination. LOF :-)
73 / Ingolf

So I learned as I read messages. I was suspicious that some meta data had gotten stripped off in the editor he used.
{^_^}

Data File Editor, found a stupid bug which I’m revisiting.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 25 February 2022 06:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] I/Q editor behavior

 

How did you edit the file?
{o.o}

On 20220224 08:00:00, michel soldevila wrote:

HI
A phenomenon that I don't understand: I made an I/Q recording, then I deleted part of it with the I/Q file editor, keeping only one hour.
The signal levels shown on the 2 pictures attached are very different between the 2 files, with the same contrast setting.
Why ?
73, Michel (F1GOC)

 

--

- + - + -

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

Data File Editor, found a stupid bug which I’m revisiting.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 25 February 2022 06:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] I/Q editor behavior

 

How did you edit the file?
{o.o}

On 20220224 08:00:00, michel soldevila wrote:

HI
A phenomenon that I don't understand: I made an I/Q recording, then I deleted part of it with the I/Q file editor, keeping only one hour.
The signal levels shown on the 2 pictures attached are very different between the 2 files, with the same contrast setting.
Why ?
73, Michel (F1GOC)

 

--

- + - + -

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

Data File Editor, found a stupid bug which I’m revisiting.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 25 February 2022 06:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] I/Q editor behavior

 

How did you edit the file?
{o.o}

On 20220224 08:00:00, michel soldevila wrote:

HI
A phenomenon that I don't understand: I made an I/Q recording, then I deleted part of it with the I/Q file editor, keeping only one hour.
The signal levels shown on the 2 pictures attached are very different between the 2 files, with the same contrast setting.
Why ?
73, Michel (F1GOC)
Full recoding duration.jpg

duration limited to one hour .jpg

 

--

- + - + -

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

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

Hi Simon.

Do you have any thoughts about supporting the Hermes accompanying filter "Alex"?
http://openhpsdr.org/alex.php
What now may be needed for the filter to follow the Hermes frequency settings.

73 / Ingolf, SM6FHZ

How did you edit the file?
{o.o}

HI
A phenomenon that I don't understand: I made an I/Q recording, then I deleted part of it with the I/Q file editor, keeping only one hour.
The signal levels shown on the 2 pictures attached are very different between the 2 files, with the same contrast setting.
Why ?
73, Michel (F1GOC)
Full recoding duration.jpg

duration limited to one hour .jpg

HI
A phenomenon that I don't understand: I made an I/Q recording, then I deleted part of it with the I/Q file editor, keeping only one hour.
The signal levels shown on the 2 pictures attached are very different between the 2 files, with the same contrast setting.
Why ?
73, Michel (F1GOC)
Full recoding duration.jpg

duration limited to one hour .jpg