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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE!

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Old 19th Aug 2023, 11:12 pm   #1
Phil G4SPZ
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Default Roberts R900 easy repair

This set arrived at my local Repair Cafe producing loud crackling from the volume control, but once treated with Servisol it transpired that the audio stages were working but there were no signals on any band. Looking at the circuit, the FM front end is a TA7358P and the AM radio is based on a TDA1220B. I deduced that the regulated 7.6 volt supply wasn’t reaching either chip, and quickly discovered that the decoupling capacitor C35 (470uF, 10V) had gone short-circuit. A replacement capacitor restored the set to normal operation.

Phil
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Old 20th Aug 2023, 10:05 am   #2
Kevin Hoyland
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Default Re: Roberts R900 easy repair

Morning Phil.
Good Work one more working radio.

Regards
Kevin.
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Old 20th Aug 2023, 10:23 am   #3
Phil G4SPZ
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Default Re: Roberts R900 easy repair

Morning Kevin, and many thanks - yes, I’ve lost count of how many radios and other electronic devices I have managed to save from landfill by the replacement of one single component costing a few pence. Probably the ‘best’ was a £350 electric feature fireplace which was dead due to a single 1Meg 1/8 watt resistor in the PSU having gone o/c!
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