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tune up help


Defpom page had nothing.
CB Tricks forum had nothing.
Quack Shack forum had nothing.
CB Radio Talk forum had nothing.
This site has nothing...

I don't want to burst your bubble; but this isn't a popular radio to own or mod.
Best thing for it, is to put a Astatic D-104 handheld mic (cost about $45) on it; that should boost your modulation a bit more w/o needing to go in and internally mod it.
Or get an DM-452 echo mic - cost about $20 and can be bought on eBay. Then, you will need to wire either the DM-452 or the D-104 mic to a D.I.N. mic plug for your TRC-503. That also may turn into a trial-and-error event; as I coundn't even find a mic wiring diagram for it. Either mic will boost your modulation.

If you are disappointed with the performance or options for that radio, you would be surprised how far $50 goes on this forum for another used radio. Other than that, maybe someone on this forum may yet know something about that radio...
 
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I hate to admit it...the corporate bas*!$$!...but google can be your pal sometimes. Many several hits on the 503 and here is one of them, a free download of the Service Manual. All the tune up points should be in there. I didn't download just to look at it but you give 'er a try:

Radio Shack TRC-503 Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics

Good luck
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oh well

I know its not a popular radio but its something to piddle with and see what i can find out about u can never tell what we may find out about it thanks on the info im just trying to learn a little:mellow:
 

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