i have a gm300 with no audio and no 16 pin adapter

wazzzzzzzzup · Post by **wazzzzzzzzup** » Fri Oct 05, 2001 7:45 pm

i have a 8 chan gm300 with no audio, but definately works fine otherwise, there is no adapter on the 16 pin connector, (normally if you remove the 16 pin adapter on the 16 pin connector the internal audio would stop. i have tried a 16 pin adapter from a 16 pin maxtrac, but it still doesnt do the job. i have tried to look at the batlabs maxtrac pinout s for 8 and 16 pin but dont really understand them to compare. do you know what particular pins to jumper to get internal audio to turn on this radio?
thanks
wazzup
****i have tried the jumpering of pins 11 and 15, it seems to work, but there is no real volume, it sounds like the volume is at bottom when the volume control is cranked up to the top, it sounds like unamplified line level audio, any more ideas would be greatly appreciated.....

<font size=-1>[ This Message was edited by: wazzzzzzzzup on 2001-10-06 00:11 ]</font>

Jack · Post by **Jack** » Fri Oct 05, 2001 7:51 pm

I think you have to jumper pins 11 and 15

jim · Post by **jim** » Sat Oct 06, 2001 6:37 am

15 and 16 !!!

wazzzzzzzzup · Post by **wazzzzzzzzup** » Sat Oct 06, 2001 8:44 am

i tried jumpering pins 15 and 16 but still dont get any audio....hmmmm

Will · Post by **Will** » Sat Oct 06, 2001 1:08 pm

Pins 15 and 16 connect the internal speaker to the radio's audio output. Pin 1 and 16 are the audio output pins for an external speaker. Pins 15 and 16 are one above each other on the outside edge of the radio, the same side as the volume control.
Do you have audio on these pins?
There may be some other "mickey mouse" modification made to the radio. Does the recieve "handset audio" appear at pin 8
of the microphone jack? Is it affected by the volume control? Use a earphone or reciever element from a telephone handset to test with.
There are a couple of jumpers in the radio that could be wrong or missing. These are three pin "Berg" male pins on the logic/audio board.
If not you need a good tech to look at it for you.

wazzzzzzzzup · Post by **wazzzzzzzzup** » Sat Oct 06, 2001 8:17 pm

i have verified that jumpering pins 16 donot work, so i have opened the radio to see the jumper settings on the logic board, what i see are these....tward the heatsink are two empty 3 pin headers p810 and p811 (i wonder if there should be a jumper on either?) next we have the following 3 pin headers from back of radio to the front....jumpered the following, p701 jumpered 2-3, p651 jumpered 2-3, p800 jumpered 1-2 and finally p601 jumpered 2-3. the model number of this radio is M34GMC29C3AA, i think this is an 8 channel radio, could someone look at thier logic board or may already know what the jumper settings are and please let me know if i have any jumpers out of place or missing? thanks

Jay G. · Post by **Jay G.** » Sat Oct 06, 2001 10:00 pm

Since you have tried using the 16 pin accessory plug, then it's obviously something more intricate. If either speaker lead was accidentally shorted or grounded, then chances are the audio amp is fried. The radio then needs to go to a repair shop for repair. I had that with one of my radios where the speaker wire under the carpet in the car shorted to ground, and fried the audio amp. Good luck!

narc29 · Post by **narc29** » Tue Oct 16, 2001 3:15 am

I had the same problem with 2 maxtracs...I was told by several others that the volume pot board in the head is usually to blame...After I swapped them out they both worked fine.