Bush TR82B problems
 

Hi all - brand new to the forum as well as vintage radios (please forgive my lack of knowledge!).

I recently inherited a Bush TR82B which I'm quite keen to see if I can get going and learn something new in the process. I've got some soldering skills (mostly from modding/repairing guitars). If it's not worth the effort it's no great loss - it looks quite pretty on the shelf anyway!

The current situation is this:

• It has a new battery in it

• Switches on, but only static comes through the speaker

• Volume and tone pots both seem to be functioning and reasonably crackle-free after some contact cleaner

• After switching between Med and Long repeatedly (to see how the mechanism worked, largely out of curiosity) it started picking up a station, albeit it with a fair amount of static. I couldn't move away from this station using the tuning dial - it was stuck on that station.

• That lasted about 10 minutes - in that 10 minutes it dropped out a couple of times, but switching to Long and back again kicked it back in.

• Now I can only very faintly hear voices and music, and it's almost all static.

The serial number is 345/06551 - I believe this is an earlier one without the AF117 transistors but I could be wrong.

Where should I start looking to diagnose its problems? Any help would be brilliant. I've attached some pictures if it makes things easier.

Thanks!

Re: Bush TR82B problems
 

Hello and welcome to the forums.

As far as I know these sets used OC series transistors.

I'd start by applying Servisol to all the pots and switches.

I'm not normally one to advocate wholesale component replacements, but those red/yellow/black Plessey electrolytic capacitors are unreliable.

The correct approach is to measure voltages and compare them with the service sheet.

http://www.service-data.com/product.php/655/1065/m10655

Re: Bush TR82B problems
 

It's probably the wavechange switch contacts which tend to oxidise.

It's clear from the photos that OC44/5 transistors are fitted which are generally reliable.

Re: Bush TR82B problems
 

I had one with similar fault, once the wave change switch has been cleaned, try a bit of GENTLE heat on the three black transistors OC44 / 45. in my set warming between finger and thumb would be enough for the set to burst into life.


John.

Re: Bush TR82B problems
 

I've recently restored one of these radios.
The wave change switch was horribly dirty/oxidised, but after careful cleaning ( Deoxit / IPA etc ), it now works fine.
I also replaced the Plessey red/yellow/black electrolytics - not known for their reliability. :thumbsup:
Stephen

Re: Bush TR82B problems
 

Brilliant - thanks everyone for their responses! I've managed to get hold of some Servisol from my in-laws so I'll get the wave change switch cleaned up once I'm back home. Will also give warming the transistors a go.

Thanks again everyone - will update with any progress as I go!

Re: Bush TR82B problems
 

Slightly off topic, but curious to know how warming Ge transistors would restore operation...

Re: Bush TR82B problems
 

Hi Keith, not sure but it worked for me, and kept working until switch off. Upon turning on again it needed warmth again, and ultimately another transistor.


John.

Re: Bush TR82B problems
 

I have not known these OC transistors to respond like that. I wonder if that was the real cause of it starting to work or if during the time you were "warming" the transistor a capacitor reformed enough to get the set going.

Mike