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 23rd May 2020, 9:20 pm   #1
60 oldjohn
Dekatron
 
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 3,959
Default Interesting Diode AA129

Was the AA129 made out of reject transistors ?

John.
__________________
My favourite text message "I'll be there in five minutes, if not read again"
60 oldjohn is offline  
Old 24th May 2020, 2:40 am   #2
Terry_VK5TM
Nonode
 
Terry_VK5TM's Avatar
 
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
Posts: 2,324
Default Re: Interesting Diode AA129

Can't answer that, but interesting that a few suppliers (eg Cricklewood, Littlediode) still seem to have stock of them, so maybe not a popular item even in it's heyday.
__________________
Terry VK5TM
https://www.vk5tm.com/
Terry_VK5TM is offline  
Old 24th May 2020, 9:59 am   #3
paulsherwin
Moderator
 
paulsherwin's Avatar
 
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,787
Default Re: Interesting Diode AA129

The fact that they have a Pro-Electron coding despite the OC71 style glass encapsulation suggests they may have been a way of disposing of old stocks or sweating obsolescent production facilities once the AC/AF series of transistors were introduced.
paulsherwin is online now  
Old 24th May 2020, 10:29 am   #4
60 oldjohn
Dekatron
 
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 3,959
Default Re: Interesting Diode AA129

You are possibly right Paul, it just looks a botched job.

John.
Attached Thumbnails
Click image for larger version

Name:	SN854122.jpg
Views:	180
Size:	121.3 KB
ID:	206609   Click image for larger version

Name:	SN854115.jpg
Views:	190
Size:	39.0 KB
ID:	206610   Click image for larger version

Name:	SN854123.jpg
Views:	176
Size:	126.7 KB
ID:	206611  
__________________
My favourite text message "I'll be there in five minutes, if not read again"
60 oldjohn is offline  
Old 24th May 2020, 10:37 am   #5
paulsherwin
Moderator
 
paulsherwin's Avatar
 
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,787
Default Re: Interesting Diode AA129

They do look like an OC71 or OC45 with the base tied to the collector.
paulsherwin is online now  
Old 24th May 2020, 1:48 pm   #6
Radio Wrangler
Moderator
 
Radio Wrangler's Avatar
 
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,801
Default Re: Interesting Diode AA129

Gives them a way to convert duds into a revenue stream. Only needs one out of two junctions to be useable.
And can be done to anything found dud right up to post packaging.

David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
Radio Wrangler is offline  
Old 24th May 2020, 2:11 pm   #7
barrymagrec
Octode
 
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,552
Default Re: Interesting Diode AA129

https://www.web-bcs.com/diode/dc/aa/AA129.html
barrymagrec is offline  
Old 24th May 2020, 5:21 pm   #8
AC/HL
Dekatron
 
AC/HL's Avatar
 
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,637
Default Re: Interesting Diode AA129

If you do a Google image search, different manufacturers have used different packages for this diode. Soldered, welded and plain two wire. Intended as a stabiliser diode.
AC/HL is offline  
Old 24th May 2020, 5:40 pm   #9
Trigon.
Hexode
 
Trigon.'s Avatar
 
Join Date: Jun 2018
Location: Buckinghamshire, UK.
Posts: 382
Default Re: Interesting Diode AA129

Full data sheet:

AA129.pdf

Cheers
Trigon. is online now  
Old 25th May 2020, 1:48 am   #10
Maarten
Dekatron
 
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,185
Default Re: Interesting Diode AA129

I seem to remember the temperature characteristic of a transistor would work better for this specific application so it might be intentional design and not a way to get rid of duds.
Maarten is offline  
Old 25th May 2020, 11:50 am   #11
bc312
Pentode
 
bc312's Avatar
 
Join Date: Feb 2005
Location: Longfield, Kent, UK.
Posts: 239
Default Re: Interesting Diode AA129

Would be interesting to separate the leadouts and test as a transistor to see the characteristics.
__________________
Leave me alone - I know what I'm doing.

BVWS member, EUG, G-QRP
Radio Bygones/Radiophile
bc312 is offline  
Old 25th May 2020, 1:02 pm   #12
AC/HL
Dekatron
 
AC/HL's Avatar
 
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,637
Default Re: Interesting Diode AA129

Newmarket never made diodes as such, but I have seen a welded lead transistor used in this way.
AC/HL is offline  
Old 25th May 2020, 1:17 pm   #13
Red to black
Nonode
 
Red to black's Avatar
 
Join Date: Mar 2010
Location: Sunderland, Tyne and Wear, UK.
Posts: 2,473
Default Re: Interesting Diode AA129

The more common version of this as I recall was the AC128 used on convergence panels of the Philips G8
__________________
I don't suffer from Insanity. I enjoy every minute of it.
Red to black is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:00 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.