Date   

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

Conrad, PA5Y
 

If there are enough excellent signals then maybe slowly the culture will change. When the manufacturers move on to a clean TX being the marketing differentiator then I am sure it will improve. Why is OT4A’s signal so bad? Almost certainly not his TS-890S unless it is grossly maladjusted. Must be his big value (sic) amplifier?

 

Imagine how bad it would be if he used an IC-7300 which only yesterday you described as excellent.  Which I demonstrated it is not!

 

73

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 23 February 2022 08:51
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Mark,

 

What your description below shows is a very poor PA somewhere in your chain. I agree that PS can clean this up and indeed should be used, but for myself the first step would be to generate as clean a signal as possible before looking at PS. Hermes Lite 2, FDM DUO and Hermes 14-bit have very clean outputs, so we’re starting from a good base. PS should not be used as an excuse for shipping a poor PA.

 

There’s a station in Belgium – OT4A – uses a TS890s and a *big* value amplifier. His signal is truly horrible, many tell him this but he doesn’t care. So even though your signal may be excellent it’s others such as OT4A who you can’t correct .

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob@...
Sent: 23 February 2022 03:07
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

[Edited Message Follows]

On Tue, Feb 22, 2022 at 01:08 AM, Max wrote:

Never quite sure what the obsession is with Pure Signal?

Max

I'd like to try and answer that, at least to the degree that I own and operate an ANAN 7000.

Firstly, strictly in terms of splatter the cleanness of my transmitted signal running PS is unmatched anywhere else in the amateur radio kingdom, including from the finest Class A amplifiers. Nothing else even comes close to the transmit splatter level of between -60 and -70 dB when using PS (I routinely observe between -62 and -65 dB as measured with a tap at the output of my AL-80B). A simple calculation reveals that at 1KW transmit level the total splatter from both sides of an SSB transmission at -62 dB IMD is less than 1 milliwatt. Think about that! At that level, another ham on a high quality receiver 3 houses away from mine could be listening on a frequency immediately adjacent to mine and he'd never know I was there. That's called being a good neighbor.

Secondly, the fact that I'm basically not wasting any power at all in splatter means that all of my transmitted signal is actual talk power. So my transmitted signal (and thus audio strength) is greater than it would be if I wasn't running PS. Basically, that's free power! In fact, I've read a lab review of an ANAN radio where the reviewer remarked that when he engaged PS he observed that the power density of the transmitted signal increased (I can't find that review atm but if I do I'll post a link).

Thirdly, the purity of the audio also improves, because the IMD component of the amplifier also adversely affects the audio signal as well as the RF signal. So my audio is not only stronger but also cleaner when I'm running PS.

Fourthly, the external sampling tap available on the back of the ANAN 7000 allows the PS algorithm to correct the IMD component for the entire PA train, including my AL-80B, such that the full strength of the signal being delivered to the antenna is cleaned up, not just the barefoot signal coming out of the ANAN.

Fifthly, there are a number of niche band slices in the HF bands where 4kHz ESSB is typically employed (3.870 and 7.235 are often active in the States) and other HF amateur freqs where 8kHz wide AM is employed. So it's certainly not overkill to strive for superior audio on amateur HF. I run an AT2035 mic (yeah, it requires 48v phantom) and I wouldn't trade it for any dynamic mic, because there's simply no comparison between a good large diaphragm condenser mic and any dynamic mic. True, my mic needs a quiet shack but I've gone to the effort to build a quiet shack.

Hope that helps,

Mark K1LSB

Edit: If I neglected to mention it, I'm a huuuge fan of PureSignal. PS is the main reason I bought my ANAN, and I'll never own another radio. As far as I'm concerned, every other radio runs a distant second place to the ANAN with regards to cleanness of the transmitted signal.


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

Simon Brown
 

Mark,

 

What your description below shows is a very poor PA somewhere in your chain. I agree that PS can clean this up and indeed should be used, but for myself the first step would be to generate as clean a signal as possible before looking at PS. Hermes Lite 2, FDM DUO and Hermes 14-bit have very clean outputs, so we’re starting from a good base. PS should not be used as an excuse for shipping a poor PA.

 

There’s a station in Belgium – OT4A – uses a TS890s and a *big* value amplifier. His signal is truly horrible, many tell him this but he doesn’t care. So even though your signal may be excellent it’s others such as OT4A who you can’t correct .

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of oldjackbob@...
Sent: 23 February 2022 03:07
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

[Edited Message Follows]

On Tue, Feb 22, 2022 at 01:08 AM, Max wrote:

Never quite sure what the obsession is with Pure Signal?

Max

I'd like to try and answer that, at least to the degree that I own and operate an ANAN 7000.

Firstly, strictly in terms of splatter the cleanness of my transmitted signal running PS is unmatched anywhere else in the amateur radio kingdom, including from the finest Class A amplifiers. Nothing else even comes close to the transmit splatter level of between -60 and -70 dB when using PS (I routinely observe between -62 and -65 dB as measured with a tap at the output of my AL-80B). A simple calculation reveals that at 1KW transmit level the total splatter from both sides of an SSB transmission at -62 dB IMD is less than 1 milliwatt. Think about that! At that level, another ham on a high quality receiver 3 houses away from mine could be listening on a frequency immediately adjacent to mine and he'd never know I was there. That's called being a good neighbor.

Secondly, the fact that I'm basically not wasting any power at all in splatter means that all of my transmitted signal is actual talk power. So my transmitted signal (and thus audio strength) is greater than it would be if I wasn't running PS. Basically, that's free power! In fact, I've read a lab review of an ANAN radio where the reviewer remarked that when he engaged PS he observed that the power density of the transmitted signal increased (I can't find that review atm but if I do I'll post a link).

Thirdly, the purity of the audio also improves, because the IMD component of the amplifier also adversely affects the audio signal as well as the RF signal. So my audio is not only stronger but also cleaner when I'm running PS.

Fourthly, the external sampling tap available on the back of the ANAN 7000 allows the PS algorithm to correct the IMD component for the entire PA train, including my AL-80B, such that the full strength of the signal being delivered to the antenna is cleaned up, not just the barefoot signal coming out of the ANAN.

Fifthly, there are a number of niche band slices in the HF bands where 4kHz ESSB is typically employed (3.870 and 7.235 are often active in the States) and other HF amateur freqs where 8kHz wide AM is employed. So it's certainly not overkill to strive for superior audio on amateur HF. I run an AT2035 mic (yeah, it requires 48v phantom) and I wouldn't trade it for any dynamic mic, because there's simply no comparison between a good large diaphragm condenser mic and any dynamic mic. True, my mic needs a quiet shack but I've gone to the effort to build a quiet shack.

Hope that helps,

Mark K1LSB

Edit: If I neglected to mention it, I'm a huuuge fan of PureSignal. PS is the main reason I bought my ANAN, and I'll never own another radio. As far as I'm concerned, every other radio runs a distant second place to the ANAN with regards to cleanness of the transmitted signal.


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Re: Elad FDM DUO - no RX / input stream #EladDUOrxtx

Simon Brown
 

OK,

 

Now I have time to think about this.

 

  1. Let’s see the firmware you have installed: Click the Options link in the Radio window, select the Firmware tab, show me this. My current firmware is below:

    Firmware        Cmd  Value
    --------------------------
    User interface  VSI  04.87
    FPGA            VSF  02.00
    USB             VSU  04.09
    Rx demodulator  VSR  01.50
    Tx modulator    VST  01.35





  2. Let’s set the maximum display scale:
    1. Ribbon Bar, View, Scale – High = 0dBM
    2. Ribbon Bar, View, Scale – Low = -160dBM
  3. Show me the logfile: Ribbon Bar, Tools, Logfile (add as an attachment).
  4. In the Radio window check Filter: {x} Low-pass.

 

I have a small idea what may be happening but to be honest I’m struggling here.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of hb9bhu@...
Sent: 19 February 2022 09:55
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Elad FDM DUO - no RX / input stream #EladDUOrxtx

 

disabeling of auto mute and NB didn't help too


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

Mark Cayton
 
Edited

On Tue, Feb 22, 2022 at 01:08 AM, Max wrote:
Never quite sure what the obsession is with Pure Signal?
Max
I'd like to try and answer that, at least to the degree that I own and operate an ANAN 7000.

Firstly, strictly in terms of splatter the cleanness of my transmitted signal running PS is unmatched anywhere else in the amateur radio kingdom, including from the finest Class A amplifiers. Nothing else even comes close to the transmit splatter level of between -60 and -70 dB when using PS (I routinely observe between -62 and -65 dB as measured with a tap at the output of my AL-80B). A simple calculation reveals that at 1KW transmit level the total splatter from both sides of an SSB transmission at -62 dB IMD is less than 1 milliwatt. Think about that! At that level, another ham on a high quality receiver 3 houses away from mine could be listening on a frequency immediately adjacent to mine and he'd never know I was there. That's called being a good neighbor.

Secondly, the fact that I'm basically not wasting any power at all in splatter means that all of my transmitted signal is actual talk power. So my transmitted signal (and thus audio strength) is greater than it would be if I wasn't running PS. Basically, that's free power! In fact, I've read a lab review of an ANAN radio where the reviewer remarked that when he engaged PS he observed that the power density of the transmitted signal increased (I can't find that review atm but if I do I'll post a link).

Thirdly, the purity of the audio also improves, because the IMD component of the amplifier also adversely affects the audio signal as well as the RF signal. So my audio is not only stronger but also cleaner when I'm running PS.

Fourthly, the external sampling tap available on the back of the ANAN 7000 allows the PS algorithm to correct the IMD component for the entire PA train, including my AL-80B, such that the full strength of the signal being delivered to the antenna is cleaned up, not just the barefoot signal coming out of the ANAN.

Fifthly, there are a number of niche band slices in the HF bands where 4kHz ESSB is typically employed (3.870 and 7.235 are often active in the States) and other HF amateur freqs where 8kHz wide AM is employed. So it's certainly not overkill to strive for superior audio on amateur HF. I run an AT2035 mic (yeah, it requires 48v phantom) and I wouldn't trade it for any dynamic mic, because there's simply no comparison between a good large diaphragm condenser mic and any dynamic mic. True, my mic needs a quiet shack but I've gone to the effort to build a quiet shack.

Hope that helps,

Mark K1LSB

Edit: If I neglected to mention it, I'm a huuuge fan of PureSignal. PS is the main reason I bought my ANAN, and I'll never own another radio. As far as I'm concerned, every other radio runs a distant second place to the ANAN with regards to cleanness of the transmitted signal.


Re: coexist SDRuno 1.41.1 with SDRconsole3.1 with RSPdx?

jdow
 

That sounds VERY much like auto-mute is turned on.
{^_^}

On 20220222 06:18:55, Kurt Hechler wrote:
Hi Folks,

did now a no antenna test like jdow suggested.

But first of all, if I switch the AGC to on  the SDR RX went quiet and no spectrum/waterfall is displayed.   So all further test are made with AGC off!  RSPdx Bandwith at start is 2MHz

Do not have a good signal generator just a Elecraft XG3 with -107dBm, -73dBm and -33dbm

First test:
Signal -73 dBm  //  IF-Gain -50 // Visual Gain 0.  Adjusting RF-Gain to 20 to show S-Meter S9.   Now putting signal to -107dBm  S-Meter shows S2 and signal is hardly heard.

Now putting signal to -33dBm  (s9 +40)  SDRconsole stop to work  (means no RX no spectrum and waterfall. Putting back to -73dBm everything RX is working spectrum and waterfall too.


My point of view:  dynamic range is bad and I can not explain why that happen now  after my update.

Repeat my measurement within SDRuno without any problem.   XG3 seems to be not so accurate.  Measure -108dBm(snr 6dB),    -75dBm(snr 40dB) and     -35dBm(snr 75dB)

My first idea HW should be okay. 

Test are made on 3520.0 kHz  (80m)

Any ideas???

As I asked:  Can I go back to 3.0.27  to do these test there?  Or do I run in trouble when if downgrade to 3.0.27. Is version 0.27 working with SDRuno 1.41.1 ???

73
Kurt





Am 21.02.2022 um 23:58 schrieb jdow:
There is a mute setting. Overload usually means you are transmitting. This prevents feedback. In your case the antenna switch made sufficient signal level change that it looked like you were transmitting. At least that's by guess.

And one important note should be appended here. If you connect the antenna and the receiver noise level goes up 6 dB. If it goes up more than 6 dB you are simply wasting dynamic range.  Add front end attenuation. That's the rule for traditional receivers.

For SDRs you can squeak out a little more dynamic range by performing the no antenna test with a signal generator giving you a fairly weak signal. SDRs are sort of magic. They can interpolate between levels. A big signal can put a signal not making 1/2 ADC step can pop out when another signal at say 3 ADC steps. How many times does it hit 2 vs 3 vs 4? You average and there is your 1/2 level signal.

The final trick is purely subjective although SDRC's SNR meter helps. Select a very weak constant signal, SNR maybe 20 dB with the gain up high. Reduce the gain until the SNR drops a couple dB. You'll be set almost perfectly. Then if you connet an antenna with a whole lot more gain, an attenuator is the appropriate fix on HF. At low HF frequencies you can get a natural noise level equivalent to a  40 dB noise figure receiver.

It is hard to accidentally make a receiver that bad. I have done that, though, for a test. Now I run my apparently deceased ProII with 30 dB of attenuation on all the time when on 75 meters. I get the same SNRs as without the attenuation. And the strong 1590 kHz or so signal a couple miles away does not overload anything.

{^_^}    (ProII is about to become an organ donor - it's RF chassis is still just fine.)

On 20220221 12:57:43, Kurt Hechler wrote:
Hi Simon,

from my understanding is the USBpower sufficent.  See attached files.

Maybe I found the problem.  If I was for example on 40m I have to move RF Gain to round about 18 to see the SSB signals. If I go now to 80m and switch from the short dipole to the LW the Console is in overload and does not show spectrum as well the RX is quiet.  If I now minimize the RF gain to round about 10 the Console comes back.  IF Gain is -45, AGC off.   I do not know such a behavior from the early version. Even with the minimized settings the RX is sometimes switching on/off.  Bay the way SDRuno do not show that behavior.

73
Kurt
sdrcons4.JPG

sdrcons3.JPG




Re: coexist SDRuno 1.41.1 with SDRconsole3.1 with RSPdx?

jdow
 

tools menu->options
Click on "Auto-mute" on the left.

On the right make sure "Enable" is not checked. The auto-mute function is on the lower right and is worth reading.

{^_^}

On 20220222 05:08:50, Kurt Hechler wrote:
Hallo jdow,

many thanks for your detailed answer!

Now I have a lot to do.

One hand: really to understand all your suggestions because my english could be better and
one the other hand to try these things out.

For me it is a difficult to understand the difference between V3.0.26 and 3.1.  Never had that "muting" phenomenon with the old version.  Did nothing else as a update.
Also I am not a programmer and so it is more then difficult to understood all these things within the SDRconsole.  But anyway I will do my best to go further with this topic.  The only thing what could happen I will learn more about SDR and Windows administrating:-)))  and I could remember that was the beginning of amateurradio, I guess.

73
Kurt, DL9FBF


Am 21.02.2022 um 23:58 schrieb jdow:
There is a mute setting. Overload usually means you are transmitting. This prevents feedback. In your case the antenna switch made sufficient signal level change that it looked like you were transmitting. At least that's by guess.

And one important note should be appended here. If you connect the antenna and the receiver noise level goes up 6 dB. If it goes up more than 6 dB you are simply wasting dynamic range.  Add front end attenuation. That's the rule for traditional receivers.

For SDRs you can squeak out a little more dynamic range by performing the no antenna test with a signal generator giving you a fairly weak signal. SDRs are sort of magic. They can interpolate between levels. A big signal can put a signal not making 1/2 ADC step can pop out when another signal at say 3 ADC steps. How many times does it hit 2 vs 3 vs 4? You average and there is your 1/2 level signal.

The final trick is purely subjective although SDRC's SNR meter helps. Select a very weak constant signal, SNR maybe 20 dB with the gain up high. Reduce the gain until the SNR drops a couple dB. You'll be set almost perfectly. Then if you connet an antenna with a whole lot more gain, an attenuator is the appropriate fix on HF. At low HF frequencies you can get a natural noise level equivalent to a  40 dB noise figure receiver.

It is hard to accidentally make a receiver that bad. I have done that, though, for a test. Now I run my apparently deceased ProII with 30 dB of attenuation on all the time when on 75 meters. I get the same SNRs as without the attenuation. And the strong 1590 kHz or so signal a couple miles away does not overload anything.

{^_^}    (ProII is about to become an organ donor - it's RF chassis is still just fine.)

On 20220221 12:57:43, Kurt Hechler wrote:
Hi Simon,

from my understanding is the USBpower sufficent.  See attached files.

Maybe I found the problem.  If I was for example on 40m I have to move RF Gain to round about 18 to see the SSB signals. If I go now to 80m and switch from the short dipole to the LW the Console is in overload and does not show spectrum as well the RX is quiet.  If I now minimize the RF gain to round about 10 the Console comes back.  IF Gain is -45, AGC off.   I do not know such a behavior from the early version. Even with the minimized settings the RX is sometimes switching on/off.  Bay the way SDRuno do not show that behavior.

73
Kurt
sdrcons4.JPG

sdrcons3.JPG




Re: Transmit settings, noise gate or downward expander?

Conrad, PA5Y
 

OK Simon thanks. I am sure that you realised that I am just (im)patiently waiting for hardware and getting bored.

 

Conrad

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 22 February 2022 16:38
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Transmit settings, noise gate or downward expander?

 

Denoiser, exists.

 

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: 22 February 2022 14:56
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Transmit settings, noise gate or downward expander?

 

I was looking at the TX audio section, which I have not used yet. I cannot see a noise gate or downward expander, perhaps I missed it. If it is not present is there any possibility of adding one? Should I go to the forum and add a user request?

 

73

 

Conrad PA5Y


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Re: Why do users do this to my servers?

allen KC2KLC
 

Never attribute to malice what you can attribute to ignorance and/or stupidity. "Maybe I'll get better reception if I turn everything up real high" might be one example (although I admit it's not terribly likely, given the level of expertise required to access a remote SDR in the first place).


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

Siegfried Jackstien
 

french press ..yepp thats good :-)

dg9bfc sigi

Am 22.02.2022 um 07:58 schrieb TOM - K2TC:

Simon –

 

Coffee is my friend all day long 😊

The K-cup machine here gets a work out….Peet’s Major Dickenson’s Blend is on auto replenishment monthly.

I think I’m going to reserve the weekends for a dedicated attempt to get back to the burr grinder and French Press….might have to try that Taylor’s Java.

 

I’m going to be looking for a 50W to 100W amp and a nice LPF board to build up for the Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card when it gets here….

I already have in the shack the HPF and Switching boards.

 

 

Tom – K2TC

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: Tuesday, February 22, 2022 1:18 AM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Coffee is my best friend in the morning.

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 21 February 2022 23:01
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Actually thin. Maybe I need to take up coffee.
{O,o}

On 20220221 14:33:53, jdow wrote:

Er thick not think. Just got up.
{O.O}

On 20220221 05:10:24, Simon Brown wrote:

Hole cutter…

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 21 February 2022 13:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Yes it was.

 

I have used both the 10E (14 bit) and 10 (16 bit). What I don’t like is lack of cooling in these designs, so I will put in a diecast box, add heatsinks and somehow cut a hole on the top for a quiet fan.

 

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: 21 February 2022 12:54
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hi Simon, can you confirm that this was with an ANAN-10E? The 14 bit device?

 

Conrad

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 21 February 2022 12:53
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I have only used V2.

 

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: 21 February 2022 10:22
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hello Simon. Did you say that you had an ANAN—10E? This is the 14bit version I think? In which case there must be a usable V2 firmware available for the 14 bit device, I would like to use it with SDRC.

 

Regards

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 19 February 2022 20:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hi,

 

From memory you don’t need to change the firmware to change the port number.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of sm6fhz
Sent: 19 February 2022 17:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Larry, I asked this question on the openHPSDR reflector and got the answer from George, K9TRV:

Port number: 1024
And you probably have to change the FW in order to change it.

That is fine with me, and i will confirm it by your method when the board arrives in late March - early April.

73 / Ingolf


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

Robert Lorenzini
 

If you had an Anan you could see the difference graphically with the two tone test.
Depending on the amp it can be quite dramatic.

Bob - wd6dod

On 2/22/2022 1:08 AM, Max wrote:
On Tue, Feb 22, 2022 at 07:06 AM, Simon Brown wrote:
Although Pure Signal can clean up a poor PA you should aim for a clean signal without resorting to Pure Signal – the IC-7300 is spectacularly good in this respect, puts all other HF rigs to shame.
Never quite sure what the obsession is with Pure Signal? I've heard and seen my own signal on remote SDRs from my HL2 and RM Italy 150W linear (run at 2/3 power for 100W to ensure no nasties) and the signal looks and sounds very tidy, with very sharply defined clean edge cut-off, no splatter and decent quality audio. What more can one want than this? I'm aiming to further improve the audio quality with a better quality microphone (but not going overboard - Shure SM57 probably). 

Seems to me most poor signals on the bands are caused by poor audio signal chain management (no excuse for this in SDRC as the audio chain monitoring and tools are great) and overdriven PA stages? What am I missing about the need for Pure Signal?

I've noticed another (possibly related) obsession recently with many radio amateurs using multiple rack mounted audio processors that are normally used in professional sound recording studios, but the output ends up in a 2.8 kHz wide SSB signal. What's the point? Some basic EQ of course does not go amiss (again offered inside SDRC) but why all the paraphernalia? No harm in it of course, just total overkill IMHO

My pro background was technically related with national UK broadcaster for 40 years so I think I know what constitutes decent quality audio. Always willing to be proved wrong of course!

Max


Re: Transmit settings, noise gate or downward expander?

Simon Brown
 

Denoiser, exists.

 

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: 22 February 2022 14:56
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Transmit settings, noise gate or downward expander?

 

I was looking at the TX audio section, which I have not used yet. I cannot see a noise gate or downward expander, perhaps I missed it. If it is not present is there any possibility of adding one? Should I go to the forum and add a user request?

 

73

 

Conrad PA5Y


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


Transmit settings, noise gate or downward expander?

Conrad, PA5Y
 

I was looking at the TX audio section, which I have not used yet. I cannot see a noise gate or downward expander, perhaps I missed it. If it is not present is there any possibility of adding one? Should I go to the forum and add a user request?

 

73

 

Conrad PA5Y


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

Kriss Kliegle KA1GJU
 

Pure signal... because of 'amateurs' like this who are 18kHz wide at a distance of 1197 miles away:



I'm sure the folks on the Intercon Net on 14.300 were happy. 🙄
Try the attached movie for the full effect!

73 Kriss KA1GJU


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

Max
 

On Tue, Feb 22, 2022 at 11:18 AM, Simon Brown wrote:

Re: Audio,

 

  • Use a decent microphone such as the Sennheiser 835, these are cheaper than HEIL.
  • Use a good compander & limiter – as in SDR Console.
Yes, agree, Sennheiser 835 is also a good choice. My bad, I meant SM58 for the Shure mic, not SM57.

SM58 and 835 very similar animals. Lot of radio amateurs seem to opt for those recording studio style condenser mics in cradles, but (by design) they pick up quite a lot of background noise, although of course they look showy which I suspect is why they are used so much! They also need phantom power (not a big issue these days - most decent USB mic boxes have it). But for close up voice mic like we want you can't beat a good solid dynamic cardioid and they are cheap too!

73

Max


Re: coexist SDRuno 1.41.1 with SDRconsole3.1 with RSPdx?

Kurt Hechler
 

Hi Folks,

did now a no antenna test like jdow suggested.

But first of all, if I switch the AGC to on  the SDR RX went quiet and no spectrum/waterfall is displayed.   So all further test are made with AGC off!  RSPdx Bandwith at start is 2MHz

Do not have a good signal generator just a Elecraft XG3 with -107dBm, -73dBm and -33dbm

First test:
Signal -73 dBm  //  IF-Gain -50 // Visual Gain 0.  Adjusting RF-Gain to 20 to show S-Meter S9.   Now putting signal to -107dBm  S-Meter shows S2 and signal is hardly heard.

Now putting signal to -33dBm  (s9 +40)  SDRconsole stop to work  (means no RX no spectrum and waterfall. Putting back to -73dBm everything RX is working spectrum and waterfall too.


My point of view:  dynamic range is bad and I can not explain why that happen now  after my update.

Repeat my measurement within SDRuno without any problem.   XG3 seems to be not so accurate.  Measure -108dBm(snr 6dB),    -75dBm(snr 40dB) and     -35dBm(snr 75dB)

My first idea HW should be okay. 

Test are made on 3520.0 kHz  (80m)

Any ideas???

As I asked:  Can I go back to 3.0.27  to do these test there?  Or do I run in trouble when if downgrade to 3.0.27. Is version 0.27 working with SDRuno 1.41.1 ???

73
Kurt





Am 21.02.2022 um 23:58 schrieb jdow:

There is a mute setting. Overload usually means you are transmitting. This prevents feedback. In your case the antenna switch made sufficient signal level change that it looked like you were transmitting. At least that's by guess.

And one important note should be appended here. If you connect the antenna and the receiver noise level goes up 6 dB. If it goes up more than 6 dB you are simply wasting dynamic range.  Add front end attenuation. That's the rule for traditional receivers.

For SDRs you can squeak out a little more dynamic range by performing the no antenna test with a signal generator giving you a fairly weak signal. SDRs are sort of magic. They can interpolate between levels. A big signal can put a signal not making 1/2 ADC step can pop out when another signal at say 3 ADC steps. How many times does it hit 2 vs 3 vs 4? You average and there is your 1/2 level signal.

The final trick is purely subjective although SDRC's SNR meter helps. Select a very weak constant signal, SNR maybe 20 dB with the gain up high. Reduce the gain until the SNR drops a couple dB. You'll be set almost perfectly. Then if you connet an antenna with a whole lot more gain, an attenuator is the appropriate fix on HF. At low HF frequencies you can get a natural noise level equivalent to a  40 dB noise figure receiver.

It is hard to accidentally make a receiver that bad. I have done that, though, for a test. Now I run my apparently deceased ProII with 30 dB of attenuation on all the time when on 75 meters. I get the same SNRs as without the attenuation. And the strong 1590 kHz or so signal a couple miles away does not overload anything.

{^_^}    (ProII is about to become an organ donor - it's RF chassis is still just fine.)

On 20220221 12:57:43, Kurt Hechler wrote:
Hi Simon,

from my understanding is the USBpower sufficent.  See attached files.

Maybe I found the problem.  If I was for example on 40m I have to move RF Gain to round about 18 to see the SSB signals. If I go now to 80m and switch from the short dipole to the LW the Console is in overload and does not show spectrum as well the RX is quiet.  If I now minimize the RF gain to round about 10 the Console comes back.  IF Gain is -45, AGC off.   I do not know such a behavior from the early version. Even with the minimized settings the RX is sometimes switching on/off.  Bay the way SDRuno do not show that behavior.

73
Kurt
sdrcons4.JPG

sdrcons3.JPG



Re: coexist SDRuno 1.41.1 with SDRconsole3.1 with RSPdx?

Kurt Hechler
 

Hallo jdow,

many thanks for your detailed answer!

Now I have a lot to do.

One hand: really to understand all your suggestions because my english could be better and
one the other hand to try these things out.

For me it is a difficult to understand the difference between V3.0.26 and 3.1.  Never had that "muting" phenomenon with the old version.  Did nothing else as a update.
Also I am not a programmer and so it is more then difficult to understood all these things within the SDRconsole.  But anyway I will do my best to go further with this topic.  The only thing what could happen I will learn more about SDR and Windows administrating:-)))  and I could remember that was the beginning of amateurradio, I guess.

73
Kurt, DL9FBF


Am 21.02.2022 um 23:58 schrieb jdow:

There is a mute setting. Overload usually means you are transmitting. This prevents feedback. In your case the antenna switch made sufficient signal level change that it looked like you were transmitting. At least that's by guess.

And one important note should be appended here. If you connect the antenna and the receiver noise level goes up 6 dB. If it goes up more than 6 dB you are simply wasting dynamic range.  Add front end attenuation. That's the rule for traditional receivers.

For SDRs you can squeak out a little more dynamic range by performing the no antenna test with a signal generator giving you a fairly weak signal. SDRs are sort of magic. They can interpolate between levels. A big signal can put a signal not making 1/2 ADC step can pop out when another signal at say 3 ADC steps. How many times does it hit 2 vs 3 vs 4? You average and there is your 1/2 level signal.

The final trick is purely subjective although SDRC's SNR meter helps. Select a very weak constant signal, SNR maybe 20 dB with the gain up high. Reduce the gain until the SNR drops a couple dB. You'll be set almost perfectly. Then if you connet an antenna with a whole lot more gain, an attenuator is the appropriate fix on HF. At low HF frequencies you can get a natural noise level equivalent to a  40 dB noise figure receiver.

It is hard to accidentally make a receiver that bad. I have done that, though, for a test. Now I run my apparently deceased ProII with 30 dB of attenuation on all the time when on 75 meters. I get the same SNRs as without the attenuation. And the strong 1590 kHz or so signal a couple miles away does not overload anything.

{^_^}    (ProII is about to become an organ donor - it's RF chassis is still just fine.)

On 20220221 12:57:43, Kurt Hechler wrote:
Hi Simon,

from my understanding is the USBpower sufficent.  See attached files.

Maybe I found the problem.  If I was for example on 40m I have to move RF Gain to round about 18 to see the SSB signals. If I go now to 80m and switch from the short dipole to the LW the Console is in overload and does not show spectrum as well the RX is quiet.  If I now minimize the RF gain to round about 10 the Console comes back.  IF Gain is -45, AGC off.   I do not know such a behavior from the early version. Even with the minimized settings the RX is sometimes switching on/off.  Bay the way SDRuno do not show that behavior.

73
Kurt
sdrcons4.JPG

sdrcons3.JPG



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

Simon Brown
 

Re: Audio,

 

  • Use a decent microphone such as the Sennheiser 835, these are cheaper than HEIL.
  • Use a good compander & limiter – as in SDR Console.

 

On VHF with Sennheiser / FDM DUO / Q5 Signal I get many unsolicited reports of very good audio, all down to the microphone and compander.

 

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: 22 February 2022 11:01
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hello Max, in many ways I agree with you. Particularly on HF. I will not be running Pure signal but I will only use my Hermes with transverters on bands that have a very low noise floor. As Simon says the Hermes is intrinsically clean with the exception of a few spurs that appear to come from the regulator. On 144 and above these should be reduced because they are significant. On 50 and 70 MHz they would not be noticeable due to the higher band noise.

 

As for those with racks of outboard, I totally agree. I suggest if these people want to hear their voices with broadcast audio then they should join an organisation that broadcasts! It has no place on the amateur bands. Thankfully these guys only frequent bands that I don’t!

 

Regards


Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Max via groups.io
Sent: 22 February 2022 10:09
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Tue, Feb 22, 2022 at 07:06 AM, Simon Brown wrote:

Although Pure Signal can clean up a poor PA you should aim for a clean signal without resorting to Pure Signal – the IC-7300 is spectacularly good in this respect, puts all other HF rigs to shame.

Never quite sure what the obsession is with Pure Signal? I've heard and seen my own signal on remote SDRs from my HL2 and RM Italy 150W linear (run at 2/3 power for 100W to ensure no nasties) and the signal looks and sounds very tidy, with very sharply defined clean edge cut-off, no splatter and decent quality audio. What more can one want than this? I'm aiming to further improve the audio quality with a better quality microphone (but not going overboard - Shure SM57 probably). 

Seems to me most poor signals on the bands are caused by poor audio signal chain management (no excuse for this in SDRC as the audio chain monitoring and tools are great) and overdriven PA stages? What am I missing about the need for Pure Signal?

I've noticed another (possibly related) obsession recently with many radio amateurs using multiple rack mounted audio processors that are normally used in professional sound recording studios, but the output ends up in a 2.8 kHz wide SSB signal. What's the point? Some basic EQ of course does not go amiss (again offered inside SDRC) but why all the paraphernalia? No harm in it of course, just total overkill IMHO

My pro background was technically related with national UK broadcaster for 40 years so I think I know what constitutes decent quality audio. Always willing to be proved wrong of course!

Max


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


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

Conrad, PA5Y
 

Hello Max, in many ways I agree with you. Particularly on HF. I will not be running Pure signal but I will only use my Hermes with transverters on bands that have a very low noise floor. As Simon says the Hermes is intrinsically clean with the exception of a few spurs that appear to come from the regulator. On 144 and above these should be reduced because they are significant. On 50 and 70 MHz they would not be noticeable due to the higher band noise.

 

As for those with racks of outboard, I totally agree. I suggest if these people want to hear their voices with broadcast audio then they should join an organisation that broadcasts! It has no place on the amateur bands. Thankfully these guys only frequent bands that I don’t!

 

Regards


Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Max via groups.io
Sent: 22 February 2022 10:09
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

On Tue, Feb 22, 2022 at 07:06 AM, Simon Brown wrote:

Although Pure Signal can clean up a poor PA you should aim for a clean signal without resorting to Pure Signal – the IC-7300 is spectacularly good in this respect, puts all other HF rigs to shame.

Never quite sure what the obsession is with Pure Signal? I've heard and seen my own signal on remote SDRs from my HL2 and RM Italy 150W linear (run at 2/3 power for 100W to ensure no nasties) and the signal looks and sounds very tidy, with very sharply defined clean edge cut-off, no splatter and decent quality audio. What more can one want than this? I'm aiming to further improve the audio quality with a better quality microphone (but not going overboard - Shure SM57 probably). 

Seems to me most poor signals on the bands are caused by poor audio signal chain management (no excuse for this in SDRC as the audio chain monitoring and tools are great) and overdriven PA stages? What am I missing about the need for Pure Signal?

I've noticed another (possibly related) obsession recently with many radio amateurs using multiple rack mounted audio processors that are normally used in professional sound recording studios, but the output ends up in a 2.8 kHz wide SSB signal. What's the point? Some basic EQ of course does not go amiss (again offered inside SDRC) but why all the paraphernalia? No harm in it of course, just total overkill IMHO

My pro background was technically related with national UK broadcaster for 40 years so I think I know what constitutes decent quality audio. Always willing to be proved wrong of course!

Max


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

Conrad, PA5Y
 

Simon regarding the IC7300. There is a very nasty noise bump at 130kHz out, this gets quite bad at reduced power, which is typically what happens when driving a PA. Look at the difference in the attached plots at 100W and 30W. The Green plot is composite noise which is what we hear on the air.  So linearity is only part of the story. On the other hand the K3S has excellent phase noise and low AM noise but lousy linearity on 6m. However who cares these days. On 6m almost all QSOs are on FT8 where we care nothing about linearity. I still care because I do contests and use SSB.

 

My ANAN-10 (and a few others) had some nasty regulator spurs so watch out for that. They can be tamed. These plots are from F6DRO, I don’t have access to mine until this evening. If you have them I can tell you how I fixed them. This is @ 28MHz

 

Regards

 

Conrad PA5Y

 

 

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 22 February 2022 08:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Tom,

 

Re: boards – the Hermes card itself is clean without Pure Signal, in fact the 10E had a very clean output at 10W. Although Pure Signal can clean up a poor PA you should aim for a clean signal without resorting to Pure Signal – the IC-7300 is spectacularly good in this respect, puts all other HF rigs to shame.

 

This year I’ll work out the Pure Signal logic – I have a lot of code in place already.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of TOM - K2TC
Sent: 22 February 2022 06:58
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Simon –

 

Coffee is my friend all day long 😊

The K-cup machine here gets a work out….Peet’s Major Dickenson’s Blend is on auto replenishment monthly.

I think I’m going to reserve the weekends for a dedicated attempt to get back to the burr grinder and French Press….might have to try that Taylor’s Java.

 

I’m going to be looking for a 50W to 100W amp and a nice LPF board to build up for the Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card when it gets here….

I already have in the shack the HPF and Switching boards.

 

 

Tom – K2TC

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: Tuesday, February 22, 2022 1:18 AM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Coffee is my best friend in the morning.

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of jdow
Sent: 21 February 2022 23:01
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Actually thin. Maybe I need to take up coffee.
{O,o}

On 20220221 14:33:53, jdow wrote:

Er thick not think. Just got up.
{O.O}

On 20220221 05:10:24, Simon Brown wrote:

Hole cutter…

 

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown
Sent: 21 February 2022 13:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Yes it was.

 

I have used both the 10E (14 bit) and 10 (16 bit). What I don’t like is lack of cooling in these designs, so I will put in a diecast box, add heatsinks and somehow cut a hole on the top for a quiet fan.

 

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: 21 February 2022 12:54
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hi Simon, can you confirm that this was with an ANAN-10E? The 14 bit device?

 

Conrad

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 21 February 2022 12:53
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

I have only used V2.

 

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: 21 February 2022 10:22
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hello Simon. Did you say that you had an ANAN—10E? This is the 14bit version I think? In which case there must be a usable V2 firmware available for the 14 bit device, I would like to use it with SDRC.

 

Regards

 

Conrad PA5Y

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Simon Brown via groups.io
Sent: 19 February 2022 20:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Hi,

 

From memory you don’t need to change the firmware to change the port number.

 

Simon Brown, G4ELI

https://www.sdr-radio.com

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of sm6fhz
Sent: 19 February 2022 17:08
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Open HPSDR Hermes (14 bit ADC, EP3C25) Transceiver Card

 

Larry, I asked this question on the openHPSDR reflector and got the answer from George, K9TRV:

Port number: 1024
And you probably have to change the FW in order to change it.

That is fine with me, and i will confirm it by your method when the board arrives in late March - early April.

73 / Ingolf


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


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


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


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

 

 


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


--

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


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

Max
 

On Tue, Feb 22, 2022 at 07:06 AM, Simon Brown wrote:
Although Pure Signal can clean up a poor PA you should aim for a clean signal without resorting to Pure Signal – the IC-7300 is spectacularly good in this respect, puts all other HF rigs to shame.
Never quite sure what the obsession is with Pure Signal? I've heard and seen my own signal on remote SDRs from my HL2 and RM Italy 150W linear (run at 2/3 power for 100W to ensure no nasties) and the signal looks and sounds very tidy, with very sharply defined clean edge cut-off, no splatter and decent quality audio. What more can one want than this? I'm aiming to further improve the audio quality with a better quality microphone (but not going overboard - Shure SM57 probably). 

Seems to me most poor signals on the bands are caused by poor audio signal chain management (no excuse for this in SDRC as the audio chain monitoring and tools are great) and overdriven PA stages? What am I missing about the need for Pure Signal?

I've noticed another (possibly related) obsession recently with many radio amateurs using multiple rack mounted audio processors that are normally used in professional sound recording studios, but the output ends up in a 2.8 kHz wide SSB signal. What's the point? Some basic EQ of course does not go amiss (again offered inside SDRC) but why all the paraphernalia? No harm in it of course, just total overkill IMHO

My pro background was technically related with national UK broadcaster for 40 years so I think I know what constitutes decent quality audio. Always willing to be proved wrong of course!

Max

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