jwpauler wrote: >Good Afternoon everyone... > >I have two Motorola Radius M120 mobile radios, each listing a model >number of M44GMC20A3AA. As far as I can tell (from looking at the >front and what's in RSS) these are two channel units, have the 40W >P.A. and include the 16-pin accessory connector. > >These units are going to be interfaced to a repeater controller for >use as a portable repeater, but I'm having a heck of a time finding >the correct pinout of the accessory connector. All of the diagrams >I've found so far refer to a "8-channel" or "16-channel" Radius and >while those diagrams get me close, some parts are missing. > >For example, I'm finding COR/COS on the first top and bottom pin on >the far right side (I think that's 15 and 16), but no diagram anywhere >lists COS at that point. I have checked to see if there is any >customization option from within the RSS (like the GM300's) and there >isn't. > >Right now I have the following working: TX AUDIO, PTT, TX GND, RX GND > >I'm trying to find/confirm: RX AUDIO, COR/COS > >Can anyone help? > >Justin > > > Justin,
From the M120 service manual: 1 External Speaker Negative 2 Microphone Audio 80mV RMS @ 60% Deviation 3 Microphone PTT 4 External Alarm (not supported) 5 Flat Transmit Audio 150mV RMS @ 60% Deviation 6 Not Used 7 Ground 8 COR Output / Receiver Unsquelched Indicator 9 Emergency Alert Input (not supported) 10 Ignition Control Input 11 Discriminator Audio Output 600mV RMS 12 Not Used 13 Switched A+ 0.5A Max 14 Remote Hook Switch (ground for PL RX) 15 Internal Speaker Positive 16 External Speaker Positive Pins 15 to 16 are normally jumpered to enable the internal speaker Ed Yoho WA6RQD
