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38k4 on Echo -- Can you record the signal?

I am working on a DSP soundcard demodulator
for the 38k4 signal from Echo and I am looking 
for volunteers to record the 38k4 signal from 
Echo using their computer soundcard. Echo is
scheduled to be transmitting at 38k4 for only 
one single day in March -- March 2 (UTC) -- 
that's Tuesday night and Wednesday in the 
United States. The 38k4 signal will be on 
435.150 MHz. 

Do you already have a radio receiver with a 
discriminator output and a wide enough receive 
bandwidth that it can pass the 38k4 signal, 
and do you have a soundcard that can record 
at 48000 samples per second or faster?

If you have all of the above, then you can 
try to record the 38k4 signal from Echo. I'll 
take whatever recordings I can get.  If you 
have a favorite soundcard recording program, 
then just set it to record 8-bit (or 16-bit) 
samples, 48000 samples per second (or faster) 
and then record as much of the pass as you 

If you don't have a suitable recording 
program, I have an "experimental" recording 
program you can try at


It's about 190k to download. There's nothing to 
install except the EXE, and the documentation is 
in the .ZIP file.  Audio level adjustment is 
critical, so I suggest you try to make a "test" 
recording BEFORE the satellite pass in order 
to adjust the levels.  The rec48000 program has
a built-in level meter to help you get the
levels correct.

Please let me know if you have any questions.

Douglas KA2UPW
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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