cobra 29LX no mic Audio

[dss56]

hi all been sick for the past 8 days bad flu.
I dug more into the audio problem and still no good news. I found out that pin 2 on mic chassis mount does not go directly to the main pc board pin 2 yellow goes to a board that is connected to the front panel board.
I have no schematic for this board. I can't find the correct 1. I have been using the Cobra 29 bluetooth the closest to the LX. The cobra 29 main boards are about 99% the same.
I have replaced almost every part in the audio chain and still no results.
The board that has the yellow wire says MIC on the pc board so the mic audio travels through this board first. Also has 2 relays on the board which i hear no clicking at all when radio is keyed.

So I have decided to put it all back together and send back.
I have never had this happen before with a radio that has no audio and cant get the correct schematic.

Guess you cant fix them all

I want to thank you all for trying to help/much appreciated

Bob here in Boston Ma.

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[MDYoungblood]

I think pin 2 is connected to the mic jack on the back of the radio, (it disconnects the audio lead on the hand mic when a headset or the bluetooth is used). Have you tried a mic there, a computer mic will work and use the regular mic to key the radio.

3's

Greg

[Bobcat]

That's my problem... I've never seen one of these radios... so I don't know how they differ in operation/function with the addition of the Bluetooth. It makes sense that, if they want to do something "Bluetoothy" with a phone... they are going to have to intercept audio.... both mic in and speaker out.... but I don't know for sure....

[MDYoungblood]

That's my problem... I've never seen one of these radios... so I don't know how they differ in operation/function with the addition of the Bluetooth. It makes sense that, if they want to do something "Bluetoothy" with a phone... they are going to have to intercept audio.... both mic in and speaker out.... but I don't know for sure....

I didn't see an answer to this and it is a pretty important question in cases like this...

Have you put a speaker in the PA jack and tried the PA?

There is no pa port in this radio cobra 29LX BT

Sorry, I missed it is a bluetooth model, that in itself creates a new set of problems. Using the menu make sure all of the bluetooth functions are turned off, it is possible the radios is stuck on "Hold", (cellphone mode). After resetting everything back to default check to see if there any audio out of the "TalkBack"?

3's

Greg

That was why I suggested turning off the bluetooth feature in an earlier post. If you have used the mic jack on the back of the radio it is possible the jack had broken and is no longer making contact back to the regular mic jack.

3's

Greg

[dss56]

The Blue Tooth is off i went through the menu and says off.
I will try the mic in the back next to see if anything.

I did inject a tone on pin 2 and it went into the board i posted and back out on a white wire to the main board. Audio tracer picked up good audio.
So the yellow wire goes to the front panel board on 1 leg of relay and on another leg back out. The relay is in the closed position so the path is from connector pin 2 to the main board. As i mentioned the relay is not activated I checked for power and there is power on the coil.

All I can say with out the full correct schematic im lost. The radio is about the same for the main pc board to a cobra 29ltd and I have tried both the 29ltd and the 29LX blue tooth the earlier version to this newer one I have. It might all sound mixed up but i think im going to close it up tomorrow and send back.

thanks for all the help i know you all wanted this fixed so we would all know if this happened to the same radio we would of known what to fix or what the problem was.

[26ICT001]

Not 100% sure but is that the radio or one of the new cobra radios with the front board conected to the main board with an edge solder connection strip? if it does have a row of solder joints holding the two boards together I would recomend you desolder and clean away all the old brittle lead free stuff and reflow with decent solder as they are renound for microscopic breakaways with any sort of vibration or bump, if its not that chasis ignor the comment. good luck all the .same