Keeping in mind the normal Micor Squelch is a dual speed squelch circuit for the audio and a second squelch (on the Squelch Gate Module) circuit for the repeater cor/cos/tx function.
If you remove the "chip" from the original circuit and use only it for cos/cor you no longer have the dual squelch circuit. You have single circuit dual-speed squelch operation. cheers, s. > At 4/18/2007 11:16, you wrote: > > > The Micor Chip squelch is a well known circuit with action/operation > > > probably based on voice band energy/information and its detection > > > against other information (or lack there off) and/or noise. > > > >The M6709 is basicly 2 op-amps, AC to DC rectifier, a window > >comparator and a audio switch. R/C filters external to the chip work > > Somehow, I feel there's a bit more to it than just the above, for it > performs so well. > > >with the op-amps to create band pass filtering that passes high > >frequency noise which is then rectified and compared to set levels at > >which point it is deterimned whether there should be a fast squelch > >closure (5 to 15mS) or a slow (about 150mS) one. > > Actually, if implemented & installed properly the fast squelch is faster > (2-3 ms), resulting in virtually complete squelch tail elimination. I find > the slow squelch to be around 300-400 ms. > > Bob NO6B >
