Hi guys,
Couple of suggestions..
1/
Would it be possible to enable MPX output from the soundcard when in FMB mode?
Obviously, you would need a 196KHz soundcard to reproduce the MPX signal.
I work in Broadcasting and being able to feed an mpx signal from an FM off air signal or STL into a transmitter would be fantastic for emergency communications (temporarily replacing a faulty analogue STL receiver etc).
MPX out could also be fed to stereo modulation monitors for testing/analysis purposes.
2/
Please, please please... FM modulation / deviation measurement. Particularly for FMB purposes.
Deviation histogram over time and seperate pilot tone deviation would be amazing
FM MPX out and FM modulation measurement
- Simon G4ELI
- Posts: 2134
- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
- Contact:
Re: FM MPX out and FM modulation m3asurement
All notes, 2) is *very* interesting.
Re: FM MPX out and FM modulation m3asurement
Used to do '1/' years back by stripping all of the de-emphasis components out of a band II tuner.
Martin
m3ghe
IO92sc
G-QRP club 6129
Use my online radios http://remoteradio.myddns.me/ or http://remoteradio.changeip.org/
m3ghe
IO92sc
G-QRP club 6129
Use my online radios http://remoteradio.myddns.me/ or http://remoteradio.changeip.org/
Re: FM MPX out and FM modulation m3asurement
I just tapped the audio signal from my Sony ST-311 tuners frome the appropriate pins of the chip before it went through the de-emphasis and used the signal to feed RDSSpy for RDS decoding.
A 16-bit 192kHz 2ch audio signal could be used to feed RDSSpy for RDS decoding - which might give a very small improvement over the excellent in-built decoder in SDR-Console on some signals.
Re: FM MPX out and FM modulation m3asurement
I am talking about 36 years ago.
Martin
m3ghe
IO92sc
G-QRP club 6129
Use my online radios http://remoteradio.myddns.me/ or http://remoteradio.changeip.org/
m3ghe
IO92sc
G-QRP club 6129
Use my online radios http://remoteradio.myddns.me/ or http://remoteradio.changeip.org/
- Simon G4ELI
- Posts: 2134
- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
- Contact:
Re: FM MPX out and FM modulation m3asurement
So, we're talking 192kHz, single channel? I am now in the right frame of mind to add this an an Extra, the output will be created for the currently active RX frequency, so if you have three RXs in action then the output will switch as you change RX selection.Sparktstic wrote: ↑Wed Sep 30, 2020 6:17 am Hi guys,
Couple of suggestions..
1/
Would it be possible to enable MPX output from the soundcard when in FMB mode?
Obviously, you would need a 196KHz soundcard to reproduce the MPX signal.
I work in Broadcasting and being able to feed an mpx signal from an FM off air signal or STL into a transmitter would be fantastic for emergency communications (temporarily replacing a faulty analogue STL receiver etc).
MPX out could also be fed to stereo modulation monitors for testing/analysis purposes.
With this approach you can listen with SDR Console as normal and feed to RDS Spy or whatever.
Re: FM MPX out and FM modulation measurement
That should work well.
Think it might need just a normal 192khz stereo channel..
If you just send out a 192khz unfiltered audio output from the demodulator (as HDSDR does, for example) to a specified VAC, that would do it.
One word of caution.. make sure you have a later version of VAC. I had issues getting an earlier (4.16) version to work, but once I updated, it was fine.
VBCable Hifi ( https://vb-audio.com/Cable/#DownloadASIOBridge ) is also good, and is free.
Think it might need just a normal 192khz stereo channel..
If you just send out a 192khz unfiltered audio output from the demodulator (as HDSDR does, for example) to a specified VAC, that would do it.
One word of caution.. make sure you have a later version of VAC. I had issues getting an earlier (4.16) version to work, but once I updated, it was fine.
VBCable Hifi ( https://vb-audio.com/Cable/#DownloadASIOBridge ) is also good, and is free.
Jim, Bournemouth IO90BR
- Simon G4ELI
- Posts: 2134
- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
- Contact:
Re: FM MPX out and FM modulation measurement
Well I don't see the point in stereo - this is the same signal as shown here, it's before demodulating. Mono 192kHz will be fine I believe.G0OFE wrote: ↑Tue Oct 20, 2020 10:55 am That should work well.
Think it might need just a normal 192khz stereo channel..
If you just send out a 192khz unfiltered audio output from the demodulator (as HDSDR does, for example) to a specified VAC, that would do it.
One word of caution.. make sure you have a later version of VAC. I had issues getting an earlier (4.16) version to work, but once I updated, it was fine.
VBCable Hifi ( https://vb-audio.com/Cable/#DownloadASIOBridge ) is also good, and is free.
- Simon G4ELI
- Posts: 2134
- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
- Contact:
Re: FM MPX out and FM modulation measurement
Assuming I get this going, which programs want this 192kHz via VAC?
I'll need to test...
I'll need to test...
Re: FM MPX out and FM modulation measurement
Had it confirmed that mono is fine.Simon G4ELI wrote: ↑Tue Oct 20, 2020 11:24 am
Well I don't see the point in stereo - this is the same signal as shown here, it's before demodulating. Mono 192kHz will be fine I believe.
RDS Spy - https://rdsspy.comAssuming I get this going, which programs want this 192kHz via VAC?
Jim, Bournemouth IO90BR