Re: Vox Circuits with Audio Delay
Wish I could claim credit and the star dust for being the first one to think it up... but nay. I first saw it over a friends house, where he was using a rack mounted semi pro-audio (band) chorus/delay unit with the NASA Shuttle Audio from a Satellite Receiver. So you could raid your old band music equipment, find a low cost (often stereo) unit off Ebay or buy a delay module made for communications audio applications. You need only parallel your COS/COS logic circuit onto the same audio source. s. I'd give his name/call-sign credit but he's a group member here and letting him find out I learned something from him is almost too much to bear/admit. But the NASA Shuttle Audio part of the story already is the give-away. > "Paul Plack" <pl...@...> wrote: > > John, I experimented with that once, and in some situations, it's the most > elegant way to derive a COS-like logic signal from an audio stream that > doesn't carry imbedded switching info. A fast, stable VOX gate listening to > the output of a squelched radio receiver can provide a very useful switching > signal. > > Set the VOX threshhold to a point where it ignores the quiescent noise level > of the squelched receiver, but triggers reliably on any trace of CTCSS tone > or ambient noise behind the party transmitting, and set the VOX delay to zero. > > Because it doesn't care about frequency, it can actually act more quickly > than a PLL CTCSS decoder, especially on the lower tones. > > 73, > Paul, AE4KR > > ----- Original Message ----- > From: JOHN MACKEY > To: Repeater-Builder@yahoogroups.com > Sent: Friday, October 23, 2009 2:45 PM > Subject: Re: [Repeater-Builder] Re: Audio Delay > > > WHY would someone be using VOX in a system linked to a repeater (such > as Echolink)? > > ------ Original Message ------ > Received: Fri, 23 Oct 2009 12:49:01 PM PDT > From: "skipp025" <skipp...@...> > To: Repeater-Builder@yahoogroups.com > Subject: [Repeater-Builder] Re: Audio Delay > SNIP > > > Helping my echolink node not get confused about > > > what it is supposed to listen to is my primary purpose > > > for having the delay. > > > > Audio delay lines are killer (great) for use with VOX > > (voice) operated logic... and a must have for many > > simulcast transmission packages. >
