Midland 203 plus uk

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Tech12
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Midland 203 plus uk

Post by Tech12 »

Hey guys got one of these dogs in that's giving me some grief, hoping someone has some useful suggestions.
Came to me after it had been "looked at" elsewhere (Along with a 78 multi that's been blown to bits), when I got it the report was no TX on any channel either AM / FM.
Things I've found so far are: Print to the Lock detector pin on the PLL chip cut, one of the via's on the PCB open & T8 smashed & hanging from the board, T9/10 had been removed & replaced tilted to one side. Repaired the print & via and replaced T8 (original not available) with T8 from a 98 +, not identical but it works, put T9/10 back into PCB properly.
Brought back TX on full 40 AM & channels 1 to 33 on FM, all spot on frequency. Channels 34 to 40 on FM have no TX & the voltage on the LD pin goes down to 0.6 volts on those 7 channels.
Be grateful for any ideas & if anyone has any service info, especially alignment info, I'd be more than happy to have some.



Andy
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Tech12
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Posts: 65
Joined: 21 Jul 2013, 08:16
Call Sign: Sparky
Location: Neath Port-Talbot South Wales

Re: Midland 203 plus uk

Post by Tech12 »

OK just to round this off, in case anyone has one of these with the same problem. I discovered pin 3 on the GP214D PLL chip goes to the vco, the voltage on this pin was 1.2v on the working channels but only 0.3 on the non working. I removed the wax from the vco & found T7 vco coil, had the core cracked & bits missing. I managed to get the core out & turn it around, after adjustment I had perfect TX on all 40 FM channels as well as the AM.

Would still like a Service manual if anyone has one.
Let us Fix it Properly.
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