Batboard

Well Im confused. Just finally got around to getting a couple of RJ-45 connectors for my GM300 so I can make a hook switch jumper and make the thing decode tone. From the pinout I see on the GM300 mic's connector, I need to put a jumper between pins 3 and 4 on the connector. I just did and when I pop it in the mic jack the Mon light is still on. Does the hook switch not go to ground? Can someone tell me the right pins to short together? Thanks.

Did you get the right pin 3 and 4? they are numbered from top to bottom.

I think so. If you are looking at the bottom of the RJ-45 connector, with pins away from you and "wire slot" closer to you, with pins facing up, I have a jumper between 3rd and 4th pin from the right side.

With your shorting plug inserted, try tapping the MON button to see if the mon led will go off.

Are you serious?

Yes, he is. The MON button will override the hook line. That said, I've double-checked one of my shorting connectors, it is definitely pins 3 & 4, which are the 3rd & 4th pins from the top of the RJ-45 plug on the GM300. If it isn't working for you, and it works with a regular mic when hung up, your pins are either wrong, or not crimped properly.

Todd

OOOO my bad. I read "try tapping the Mon light" like there was a bad connection. Well I just tried the Mon button with the connector in the socket and it still doesnt go out. If I hold the mon button the squelch opens up completely. I will bum a regular mic from a friend in the next day or so, probably tommorow. I only have a desk mic here. Ill try it out.

The desk mic should work too. The monitor key on the desk mic opens the tone squelch to monitor before transmitting. It performs the same function as taking the mobile mic off hook.

And you're correct - holding the monitor button on the face of the radio does open the carrier squelch completely. One quick tap is how one switches between CSQ and PL/DPL on that radio - with the mic hung up.

Good luck,

Ok I borrowed my friends hand mic, which I know works fine on his GM300. I put it on this radio and into the clip and the mon light is still on. I push the mon button and nothing happens. Is there a programming setting that will keep it open constantly? Im gonna test the voltage on those pins in a few minutes and let you know what i find.

Well I measured the voltage on pins 3 and 4 and read 4.42VDC so I guess they are wired right. Perhaps I didnt put in a RX tone on the channel im on? Would that make the Mon light stay on anyways? Ill have to look to see if that acc connector is programmed wrong. This is an 8ch radio and I didnt think you could program the 8ch models' acc connector. But ill check, soon as I find a new 9volt

Measuring from pin 7 to pin 14 I get 0 volts with the shorting plug inserted or not. Does that mean that internal jumper in not in the right position?

I didnt test pin 14 with the mic keyed. I see 8 jumpers but none say ju something on them.

I mean 4 jumpers. typo

Ok I tried it without that jumper, put in the rj-45, mon still on, pushed mon button, still nothing. Moved that jumper to the other position (as shown in picture) still nothing. Here is a pic of my board and also one of the shorting pin im using.

I measure no voltage between the left pin and ground, mic connector in or not. Also I DO read a short from the left pin to ground (tested with no power cable attached and no mic jumper installed). So I assume the transistor you speak of is shorted. Is there an easy way to fix this thing without replacing the transistor? I would have no use of ever using the Mon function.

That did it! I can still hit the mon button to turn mon back on now, thats good enough for me. Thanks for stepping me thru that Nand. What would have caused that transistor to fail? Improper mic wiring?