UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Success Stories

Notices

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!

Closed Thread
 
Thread Tools
Old 19th Aug 2023, 11:12 pm   #1
Phil G4SPZ
Dekatron
 
Phil G4SPZ's Avatar
 
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,728
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
Attached Thumbnails
Click image for larger version

Name:	IMG_7585.jpg
Views:	95
Size:	82.6 KB
ID:	283599   Click image for larger version

Name:	IMG_7575.jpg
Views:	83
Size:	94.9 KB
ID:	283600  
__________________
Phil

Optimist [n]: One who is not in possession of the full facts
Phil G4SPZ is offline  
Old 20th Aug 2023, 10:05 am   #2
Kevin Hoyland
Heptode
 
Join Date: Feb 2009
Location: Rotherham, South Yorkshire, UK.
Posts: 558
Default Re: Roberts R900 easy repair

Morning Phil.
Good Work one more working radio.

Regards
Kevin.
Kevin Hoyland is offline  
Old 20th Aug 2023, 10:23 am   #3
Phil G4SPZ
Dekatron
 
Phil G4SPZ's Avatar
 
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,728
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!
__________________
Phil

Optimist [n]: One who is not in possession of the full facts
Phil G4SPZ is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 4:20 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.