Strange Radio Problem

BrianBr · Post by **BrianBr** » Thu Dec 06, 2001 5:50 pm

I just got a GTX mobile that acts very strange. A plug came with the radio, in the 16-pin connector. When power is applied, the radio powers up, no matter what the power switch on the face is set to. When the 16-pin plug is removed, it powes off. When the radio is switched on without the plug in place, it powers on momentarily, then powers off. I ran it through and programmed our frequencies, with the plug in, and all went well. After programming, the radio acts the same way, power wise, but then I found that with the plug in, the control head is non-operative. No PTT or channel selection. The 16-pin plug jumps pins 8 and 10 and it jumps pins 15 and 16. (Counting pins looking into connection top left to bottom right). The usual plugs for the speaker jump pins 14 and 15. This one is driving me crazy. Anyone know why this is happening? Anyone know the pinouts for the GTX 16-pin?

10-95 · Post by **10-95** » Thu Dec 06, 2001 6:00 pm

Disconnect pins 15 and 16 and give it a try.

BrianBr · Post by **BrianBr** » Thu Dec 06, 2001 6:21 pm

Same thing. Hmm. This is very strange. I need to find out if this is bad, so I can call in the big guns.

BrianBr · Post by **BrianBr** » Thu Dec 06, 2001 6:33 pm

Ok ok. I found out what the connect is. The jump of pins 9 and 7 are (9 - Emergency Switch) (7- Ground). So, the thing was wired with the emergency switch on. With it off the radio does not power up beyond all display on. IOW, no good power beep. Does this mean the radio is a dead, scam radio??

Post by **wavetar** » Thu Dec 06, 2001 6:40 pm

You need to apply 12 volts to pin 10 of the accessory connector in order for the radio to work properly. You shouldn't need pins 7 & 9 jumpered. Also make sure pins 16 & 13 are jumpered for internal speaker, NOT pins 16 & 15 like for Maxtracs. Sounds like somebody stuck a Maxtrac plug on the unit.

Todd

BrianBr · Post by **BrianBr** » Thu Dec 06, 2001 6:51 pm

Very strange. Is there some sort of setting for that? None of the other GTX mobiles need the 12 volts on pin 10 to operate. But yes, this seems to get the radio to beheve properly. Thanks.

Post by **wavetar** » Fri Dec 07, 2001 4:55 am

Up until recently, all GTXs required ignition sense on pin 10 to operate, from the factory. There is a spot inside you can place a jumper or chip resistor to allow for use without ignition sense. Lately I've noticed that the GTXs seem to be coming with this chip resistor (10K, I think) already installed.

Todd