Hello Brendan,
Things to check:
In GQRX make sure you have selected Narrow FM, Max Dev (at least) 5KHz, Tau 100us. Audio Gain around -15dB.
For audio piping/routing I use pavucontrol. In the recording tab make sure that QSSTV is recording from "Monitor of build-in audio stereo" and it is not muted.
Finally on QSSTV make sure you have selected the correct SSTV mode. In my experience the auto mode sometimes fails to detect the correct SSTV mode.
I hope this helps!
73 Apostolos, SV1LJJ
On Sat, 2023-10-28 at 16:57 +0000, Brendan N0BML via AMSAT-BB wrote:
Greetings!
This morning I tried to capture the SSTV images from the ISS using GQRX with an RTL-SDR v4 radio without much luck. My setup is Gpredict to track the satellite and control the frequency in GQRX, then I pipe the audio from GQRX to QSSTV to decode the audio and save the image. This has worked well in the past during previous SSTV events. However it's been a minute and during the 9:18 PT pass this morning I was unable to decode any images. My cheap Baofeng radio was sitting on the table tuned to 145.800 MHz and I heard the transmission clearly so I know the ISS was transmitting and I was able to receive the signal.
Does anyone also use GQRX with the RTL-SDR radio? Can you share screen shots of your "Input", "Receiver", and "FFT" settings pages? I'm finding wildly different information about what to use and would like to join in the fun during this event.
Thanks! B