MT2000 Speaker Problem

[Yosh]

I'm glad to see the board is back up!

I have a question for those Jedi series experts out there. I am having an intermittent problem with the internal speaker on my MT2000, which is a bit unique (I think?).

Occasionally when receiving, the internal speaker stops working. I can tell that the radio is receiving a signal because the busy light starts blinking, and if I hit the monitor button (thinking that it was a co-channel station with a different PL), I still get nothing out of the speaker. Also, if I connect a speaker mic, the radio works as expected.

Trying to find the cause of the problem, I removed the front cover assembly for an inspection. Not seeing anything obvious, I reconnected the front cover flex, connected the battery and antenna, turned the radio on and tried poking around. I found that if I squeeze the bottom-right corner of the shield against the PCB below it, the speaker started working. As soon as I let go, the speaker would stop working.

Thinking that I found the cause of the problem, I made sure that the shield was contacting all of the ground pads on the PCB, and that there was sufficient pressure against the PCB and the rear chassis. This didn't work.

I've taken the radio apart a several times now, each time trying to make sure that everything was assembles correctly and that everything was touching where it is supposed to, all with no success. I even went back and flowed a bit of soldier over what looked like a wear patch on some of the ground contacts on the top and bottom of the PCB.

Still, the speaker will not function unless I squeeze the shield on the lower-right corner. I don't think the problem is in the J701 (connection from PCB to front cover flex), because I have tried to wiggle it around and didn't notice any crackles, etc. Again, only squeezing the shield against the PCB has brought the speaker back to life. I'm curious if AMP3OUT (Ext speaker) and AMP1OUT (Int. speaker) have different grounds? I am really hoping that there isn't a problem with the U702 internally or in the connection between U702 and the PCB, as I have no way to fix this type of SMT.

Thanks for reading, and if anyone has any input, I thank you in advance!!! Anyone have an extra MT2000 controller board that they want to sell???

-
Yosh

[Matt]

I'm having somewhat the same problem with my HT1000, but it's with the mic, not speaker. I've connected the external speaker mic to it, and I can use that to talk on, and I can receive fine with the internal speaker. I took it apart, reset the flex on it and it still won't work. Any idea's? I'm thinking the mic has gone bad.

[Nand]