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 > Components and Circuits

Notices

Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets.

Closed Thread
 
Thread Tools
Old 6th Apr 2008, 12:59 pm   #21
geofy
Retired Dormant Member
 
Join Date: Jun 2006
Posts: 1,798
Post Re: It's not only AF117s which fail......!

Quote:
Originally Posted by 'LIVEWIRE?' View Post
Dov by the way is 'Deutsch-Osterreichische Buchhandels-und Verlags gmbh, Munchen'=German-Austrian Book Distributors, Munich.
Thought that is what it meant The A-Z sounds a useful book though I wonder why there are so many transistor types sometimes as they all do basically the same thing, especially as just a few get well known. Mullard seem to have one manufacturer or type of application on mind when they state what a transistor is for. The AC types will last well if used with a certain amount of caution, any small germanium transistor tends to be delicate.

Geof
geofy is offline  
Old 6th Apr 2008, 3:54 pm   #22
howard
Nonode
 
howard's Avatar
 
Join Date: May 2005
Location: Godalming, Surrey, UK.
Posts: 2,593
Default Re: It's not only AF117s which fail......!

Hello,

I keep a huge stock of AF124-AF127 transistors to replace AF114-AF117s as they are the most likely transistors to fail. I also keep a stock of AC125, AC126, AC127 and AC128s to replace OC71, OC74, OC75, OC81D and OC81s and their Newmarket clones as all the latter occasionally fail. Later AC187 and AC188s occasionally fail too.

Howard
howard is offline  
Old 6th Apr 2008, 6:37 pm   #23
geofy
Retired Dormant Member
 
Join Date: Jun 2006
Posts: 1,798
Post Re: It's not only AF117s which fail......!

Quote:
Originally Posted by howard View Post
Hello,

I keep a huge stock of AF124-AF127 transistors to replace AF114-AF117s as they are the most likely transistors to fail. I also keep a stock of AC125, AC126, AC127 and AC128s to replace OC71, OC74, OC75, OC81D and OC81s and their Newmarket clones as all the latter occasionally fail. Later AC187 and AC188s occasionally fail too.

Howard
All of the germanium transistors are more likely to fail than silicons, though I still have radios with original AF11* and OC* types that work with no problems, some of these work all day on power supplies. What can kill a transistor is to have the base bias set too high, as well as any whiskers that might develope.

Geof

Last edited by geofy; 6th Apr 2008 at 6:51 pm.
geofy is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 7:34 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.