You can realistically listen to 2 receivers at the same time, maybe more if you can set the squelch on one or two of them. Even this can get confusing if the transmission subject is the same (i.e 3 SAR frequencies).
Since setting up a computer to sit there all day with nothing to do but record audio I’ve been taking a shortcut to the best parts of the days radio activity. By plonking a receiver on a certain frequency and starting a free program like Audacity to record, it lets me come back later and review the whole days radio traffic quickly.
Shrinking the entire length of audio to fit on the screen shows straight away what’s “dead air” and what’s worth listening too. This setup works much better when there’s squelch involved as you can see a clear difference between audio/no audio.
With a big enough hard drive on the computer you can record a very long piece of audio, currently there’s over 4 days of recoding time left on the computer I’m using. Once you’ve looked at the audio you can always chop out the boring bits and use the same Audacity recording program to create a nice, tidy MP3 file.
Doing things this way gives me time to check out other frequencies without having my main shortwave receiver tied up all day on one channel. You can even record data modes this way then run them through a decoding program in your own time.
Below is one such MP3 file made up of about an hours condensed signals received on the 5680 KHz search and rescue frequency.
If your interested in using something like this, the free Audacity software can be found here. The program isn’t very demanding and you’ll find all the minimum computer specs on the download page.
Just be sure to set the audio levels properly and remember to leave the computer/shortwave radio combination on if you go out.
P.S Please let me know what you think of the quality of this MP3 as I,m still playing with the bit rate and conversion process 🙂