doug <dmcgarr...@optonline.net> writes: > On 08/12/2015 10:46 PM, Joe Pfeiffer wrote: >> I'm reasonably confident there must be a better place to post this than >> this newsgroup, so answers telling me where to look will be just as >> welcome as any that address the question! I'm a Debian user, so this is >> where I'm trying first.... >> >> Is there a pulseaudio module that will detect when an audio source isn't >> silent, and mute other sources in that cases? >> >> It may be more clear if I describe my particular desire use case. I >> have a ham radio, whose audio output I can plug into my sound card >> input. I'd like to be listening to music, but when a call comes in on >> the radio have it mute any other audio. >> >> Any thoughts? >> >> > I suspect that your ham radio is VHF--2 meters, or possibly 440MHz, > since you say "when a call comes in."
Yes, it's a 2m/70cm HT (a cheap Baofeng, I confess). > Therefore, the radio certainly has a squelch circuit. As a ham, you > should be familiar enough with electronics > to find a voltage in the radio that switches level when the squelch is > activated or deactivated. You can > buffer this voltage with a transistor or a digital comparator, and use > it to control the music via a relay. > > Hint: squelch circuits usually (but not always) are controlled by the AGC. Well, yes... the squelch is actually software-controlled in the radio, but there is a line I could use to detect when it comes off. I guess I wasn't clear enough about the environment: I want to route the audio out from the HT through my computer, and I'm listening to music on that same computer. An all-software solution is certainly possible; the question is whether it exists already.
