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-- Monday, 08 August 2016, 19:45 PM --
Yes I have tried different mic and no change same thing out of pa very little sound volume turned all the way up should hurt your ear drum with ear phones in you can barely hear anything on WX
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Specs for the TDA2003 is here : https://downloads.cobra.com/CB/Models/2 ... 03data.pdf" onclick="window.open(this.href);return false;
Since the TDA2003 audio IC is getting hot one of two things is happening , either :
1/ The output of the IC is being shunted to ground (most likely)
2/ The input voltage to the IC is far too high (less likely)
First thing to check is that the TANG (Metal mounting tab) of the TDA2003 IC is not grounding to the chassis or PCB ground of the radio.
Is the insulating mica washer in place and intact without any damage?
Is the correct screw and insulating washer being used on the IC? - It will either be held on with a PLASTIC screw or a metal screw with a plastic washer to insulate the tang from the chassis.
The tang is internally connected to pin 3 of the TDA2003 - pin 3 is ground for the IC but all grounds are not the same in the radio and you do NOT want PCB ground and Chassis ground being connected together via the IC.
If that is OK , it could well be a shorted electrolytic capacitor - C44 is the most likely candidate for this problem as it goes straight from the IC's output to PCB ground.
If C44 is OK , check C48 , C42 , C73 , C35 , C39
Pin 5 on the TDA2003 is the supply voltage to the IC - looking at the diagram it is getting full 13.8 volt supply via the on/off switch so it's probably not worth checking assuming your power supply is only putting out around 13.8 volts ?
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