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Radio Make and Model: superstar 3900 el
PCB Number:
PLL Number:
Test gear available:multimeter
Symptoms:very lowTX fm audio

What is working:RX audio

What has been tried:Nothing

Did it suddenly happen ?progressively:
Anything else that may be of help?: when the radio is just turned on the audio is perfect but as the radio is on for a period of time the audio goes very low to almost zero

John,
You need to fit a small heatsink to the audio chip after moving it away from the chassis as it is when standard.
You will also have to re-fit the large electrolytic capacitor by extending it's pins so it can be bent out of the way of the new heatsink.
This work should have been done by the seller before you bought it.
Happy Christmas to all.
Dave.

Thanks Dave
Merry Christmas
Dave can you please give me the location of the audio chip on the radio
Many Thanks John

The drawing should help you find it.
Dave.

Cheers Dave
Thank you for your help
John

Hi Dave
Me again the audio chip has a small heatsink behind it
i have replaced the audio chip with a new one but the problem is still there the radio is 100% when first turned on but about an hour later the audio starts to go is there any other component what will cause this also i have noticed the outside of the mic socket gets hot be very gratefull for any help
regards John

John,
I misread your problem, you are asking about the TX audio and I've given you info on the RX audio for radios with the TDA2003 audio chip, sorry.

no worries Dave
shall we start again then lol

hi again
just wondering if anyone has got a soloution to this problem

Thanks for the post...