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Raspberry Pi On-Board Audio?


Pete Moscatt
 

I am setting one of my older Pi 3 B+ boards up for Amateur Radio.
Do you believe the on-board audio is adequate enough to use on modes like PSK, RTTY, FT8,...  ?
Or am I better off getting a Sound Card USB dongle?


Pete    VK4CCV


Bob
 

Pete, I’ve had luck with the on board audio using JTDX and WSJT-X.

Cheers/73
Bob K4RCG

On Fri, Jun 12, 2020 at 20:35 Pete Moscatt <pgmoscatt@...> wrote:
I am setting one of my older Pi 3 B+ boards up for Amateur Radio.
Do you believe the on-board audio is adequate enough to use on modes like PSK, RTTY, FT8,...  ?
Or am I better off getting a Sound Card USB dongle?


Pete    VK4CCV


David Ranch
 

Starting with simple and inexpensive, I would recommend this board:

   https://fe-pi.com/products/fe-pi-audio-z-v2


Next up would be a good quality USB sound card as they generally work well too (cheap devices can give you issues):

   https://www.amazon.com/Syba-external-Adapter-Windows-C-Media/dp/B001MSS6CS


With any of these above solutions, you'll still need to assert PTT on your radio.  The solution here depends on what radio you have.  You can construct a very simple PTT circuit to a GPIO pin on your raspberry pi and connect it to it's microphone or 6pin DATA jack.  You could use CAT control from a USB to Serial adapter connected from your Raspberry Pi to your radio (if it supports CAT control), etc.  Do NOT consider using VOX as it's far more trouble than it's worth.

If you want highend where you also want say Winkeyers, support multiple radios, real volume knobs, etc, I do love this one.  It works well on LInux and Windows but not so great on Macs:

   https://timewave.com/product/navigator-sound-card-modem/


Btw, many people prefer the simplicity of a SIgnalink sound device.  I personally find them to be expensive and bring in gotchas around PTT delays, signal levels, etc.

--David
KI6ZHD


On 06/12/2020 05:32 PM, Pete Moscatt wrote:
I am setting one of my older Pi 3 B+ boards up for Amateur Radio.
Do you believe the on-board audio is adequate enough to use on modes like PSK, RTTY, FT8,...  ?
Or am I better off getting a Sound Card USB dongle?


Pete    VK4CCV


Larry Howell
 

Hi Pete,

The on-board RPi audio is very crude as it uses a HW timer and PWM to create audio that the human ear smooths to give usable audio, but has too much distortion for any of the sound card digital modes.  I use a USB sound dongle (Sabrent USB Stereo Sound Adapter) I bought on Amazon for 7USD.

Larry AC8YE 


On Fri, Jun 12, 2020 at 8:35 PM Pete Moscatt <pgmoscatt@...> wrote:
I am setting one of my older Pi 3 B+ boards up for Amateur Radio.
Do you believe the on-board audio is adequate enough to use on modes like PSK, RTTY, FT8,...  ?
Or am I better off getting a Sound Card USB dongle?


Pete    VK4CCV


Pete Moscatt
 

Thanks Bob,

I will give that a go first, but I like the board that Dave has mentioned, which poses another question.
I would have a RTC occupy the first couple of header pins, so, if I was to go down that road and put this card in ( https://fe-pi.com/products/fe-pi-audio-z-v2),
how does one put additional components on if the header pins are already taken?

Pete


N5XMT
 

Pi has no audio input, so for rx you'd still need a USB soundcard for it

On Jun 12, 2020, at 17:35, Pete Moscatt <pgmoscatt@...> wrote:
I am setting one of my older Pi 3 B+ boards up for Amateur Radio.
Do you believe the on-board audio is adequate enough to use on modes like PSK, RTTY, FT8,...  ?
Or am I better off getting a Sound Card USB dongle?


Pete    VK4CCV


N5XMT
 

You can get "stacking" header connectors.  They have longer pins.  You put the larger board on the stacking pin header, plug that into the pi, then the RTC can go on top of that

On Jun 12, 2020, at 18:26, Pete Moscatt <pgmoscatt@...> wrote:
Thanks Bob,

I will give that a go first, but I like the board that Dave has mentioned, which poses another question.
I would have a RTC occupy the first couple of header pins, so, if I was to go down that road and put this card in (  https://fe-pi.com/products/fe-pi-audio-z-v2),
how does one put additional components on if the header pins are already taken?

Pete


Brent DeWitt
 

I haven't seen any of the "dongle" style USB audio adapters that have the stereo input needed for I-Q demod.  Can anyone else recommend one?  

Brent, AB1LF


John Tetreault (WA1OKB)
 

Get the FePi or similar....most USB ones are junk


On Sat, Jun 13, 2020, 10:40 AM Brent DeWitt <bdewitt@...> wrote:
I haven't seen any of the "dongle" style USB audio adapters that have the stereo input needed for I-Q demod.  Can anyone else recommend one?  

Brent, AB1LF


David Ranch
 


I imaging you want a wide sampling soundcard to get the broadest waterfall. Correct?  If so, you need to look for 96 or 192Khz soundcards that are compatible with Linux.  I did a LOT of researching (I would have to dig for all my notes, some experimentation with say an old SoundBlaster X-fi, but the results were always pretty poor for me.  There are some custom designed sound devices that offer a flat 192Khz of stereo audio in but they aren't cheap.  Here are some links:

   http://www.telepostinc.com/soundcards.html


After experimenting with I/Q sound cards and their resulting very strong DC spike, I then tried RTL dongles which gave me a much wider 2.4Mhz waterfall, much better signals, and reduced DC spike.  I then moved to an Airspy R2 unit with a 8Mhz wide waterfall, very good dynamic range, and no DC spike and I've been a very happy user since. 

--David
KI6ZHD


David Ranch
 


I agree with Brent, the Fe-PI units are very nice and since they use the I2S bus, they avoid some known USB issues with older Raspberry PIs.  The bummer here is that these boards go out of stock often.  I checked yesterday where they were in-stock but in checking today, they are now out of stock.  :-(  You'll have to check every few weeks to to see when they might come back into stock.

There are other I2S cards out there like this one:

   #audio injector card
   https://www.amazon.com/Audio-Injector-Zero-sound-Raspberry/dp/B075V1VNDD/ref=sr_1_2?dchild=1&qid=1591041080&sr=8-2&srs=15482353011

It's not as flexible input wise compared to the FePi and I've heard reports that it might be susceptible to RFI but it might be worth a try.  Unfortunately, it TOO is out of stock. 

--David
KI6ZHD


On 06/13/2020 07:53 AM, John Tetreault (WA1OKB) wrote:
Get the FePi or similar....most USB ones are junk

On Sat, Jun 13, 2020, 10:40 AM Brent DeWitt <bdewitt@...> wrote:
I haven't seen any of the "dongle" style USB audio adapters that have the stereo input needed for I-Q demod.  Can anyone else recommend one?  

Brent, AB1LF


N5XMT
 

Which Fe-Pi board do you recommend?  there are several listed on their site.


On Sat, Jun 13, 2020 at 9:15 AM David Ranch <rpi4hamradio-groupsio@...> wrote:

I agree with Brent, the Fe-PI units are very nice and since they use the I2S bus, they avoid some known USB issues with older Raspberry PIs.  The bummer here is that these boards go out of stock often.  I checked yesterday where they were in-stock but in checking today, they are now out of stock.  :-(  You'll have to check every few weeks to to see when they might come back into stock.

There are other I2S cards out there like this one:

   #audio injector card
   https://www.amazon.com/Audio-Injector-Zero-sound-Raspberry/dp/B075V1VNDD/ref=sr_1_2?dchild=1&qid=1591041080&sr=8-2&srs=15482353011

It's not as flexible input wise compared to the FePi and I've heard reports that it might be susceptible to RFI but it might be worth a try.  Unfortunately, it TOO is out of stock. 

--David
KI6ZHD


On 06/13/2020 07:53 AM, John Tetreault (WA1OKB) wrote:
Get the FePi or similar....most USB ones are junk

On Sat, Jun 13, 2020, 10:40 AM Brent DeWitt <bdewitt@...> wrote:
I haven't seen any of the "dongle" style USB audio adapters that have the stereo input needed for I-Q demod.  Can anyone else recommend one?  

Brent, AB1LF


N5XMT
 

NM  Same codec, just different form factor


On Sat, Jun 13, 2020 at 10:09 AM David Cooley <dacooley@...> wrote:
Which Fe-Pi board do you recommend?  there are several listed on their site.


On Sat, Jun 13, 2020 at 9:15 AM David Ranch <rpi4hamradio-groupsio@...> wrote:

I agree with Brent, the Fe-PI units are very nice and since they use the I2S bus, they avoid some known USB issues with older Raspberry PIs.  The bummer here is that these boards go out of stock often.  I checked yesterday where they were in-stock but in checking today, they are now out of stock.  :-(  You'll have to check every few weeks to to see when they might come back into stock.

There are other I2S cards out there like this one:

   #audio injector card
   https://www.amazon.com/Audio-Injector-Zero-sound-Raspberry/dp/B075V1VNDD/ref=sr_1_2?dchild=1&qid=1591041080&sr=8-2&srs=15482353011

It's not as flexible input wise compared to the FePi and I've heard reports that it might be susceptible to RFI but it might be worth a try.  Unfortunately, it TOO is out of stock. 

--David
KI6ZHD


On 06/13/2020 07:53 AM, John Tetreault (WA1OKB) wrote:
Get the FePi or similar....most USB ones are junk

On Sat, Jun 13, 2020, 10:40 AM Brent DeWitt <bdewitt@...> wrote:
I haven't seen any of the "dongle" style USB audio adapters that have the stereo input needed for I-Q demod.  Can anyone else recommend one?  

Brent, AB1LF


Dave Slotter, W3DJS
 

Pete,

The Raspberry Pi "as-is" does not have a microphone input, so you're going to need to either a) get radio with USB sound card (Icom IC-7300 is what I use), or b) a USB sound card dongle or c) Northwest Digital Radio DRAWS(tm) board. While I'm not aware that DRAWS(tm) has sound in, it does have two connectors for radios which I would believe could carry sound.

--
- Dave
  W3DJS


Pete Moscatt
 

Thanks To All,

Wasn't expecting to get such a large number of responses......   thank you all.
I have a lot to ponder but also realized that there are options out there making the Pi is such a diversified product.

Everyone, thanks again.

Pete VK4CCV


billth87
 

I used a Behringer U-Control UCA222 USB Audio Interface from Sweetwater  (www.sweetwater.com ) with my old Windows box for WSJT-X.  It's a stereo audio interface.  It worked fine.  I did not try it with my Raspberry Pi.  I don't know if they have drivers for the Raspberry Pi.
Bill, N9BT


w9ran
 

I've had good luck with both the Fe-Pi Z-V2 and StarTek ICUSBAUDIO (external USB) soundcards.    Linux recognizes them both and they work well with alsa, portaudio and PulseAudio.    Be advised that the are other StarTek models that are more expensive but do not offer 96K as this one does:

https://www.startech.com/Cards-Adapters/Sound/USB-Audio/USB-to-Audio-Converter-External-SPDIF-Sound-Card~ICUSBAUDIO2D

73, Bob W9RAN


Ray Wells
 

I've used the Behringer UCA202 on Linux, including the RPi, and it works fine as plug and play. The UCA202 has RCA stereo line in and line out as well as SPDIF (Toslink) out. It's a 48kHs device. The card shows in Alsamixer but there are no adjustable controls. I have used one of mine with Direwolf. The 202 and 222 appear identical electrically, with the former being silver in color and the latter being red.

Ray vk2tv

On 14/6/20 10:49 am, billth87 via groups.io wrote:
I used a Behringer U-Control UCA222 USB Audio Interface from Sweetwater  (www.sweetwater.com <http://www.sweetwater.com>) with my old Windows box for WSJT-X.  It's a stereo audio interface.  It worked fine.  I did not try it with my Raspberry Pi.  I don't know if they have drivers for the Raspberry Pi.
Bill, N9BT
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