|
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. |
|
Thread Tools |
23rd May 2020, 9:20 pm | #1 |
Dekatron
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 3,988
|
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" |
24th May 2020, 2:40 am | #2 |
Nonode
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
Posts: 2,340
|
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.
|
24th May 2020, 9:59 am | #3 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,966
|
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.
|
24th May 2020, 10:29 am | #4 |
Dekatron
Join Date: Dec 2004
Location: East Yorkshire, UK.
Posts: 3,988
|
Re: Interesting Diode AA129
You are possibly right Paul, it just looks a botched job.
John.
__________________
My favourite text message "I'll be there in five minutes, if not read again" |
24th May 2020, 10:37 am | #5 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,966
|
Re: Interesting Diode AA129
They do look like an OC71 or OC45 with the base tied to the collector.
|
24th May 2020, 1:48 pm | #6 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,899
|
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 |
24th May 2020, 2:11 pm | #7 |
Octode
Join Date: Dec 2017
Location: Morden, Surrey, UK.
Posts: 1,560
|
Re: Interesting Diode AA129
|
24th May 2020, 5:21 pm | #8 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,642
|
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.
|
25th May 2020, 1:48 am | #10 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,203
|
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.
|
25th May 2020, 11:50 am | #11 |
Pentode
Join Date: Feb 2005
Location: Longfield, Kent, UK.
Posts: 240
|
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 |
25th May 2020, 1:02 pm | #12 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,642
|
Re: Interesting Diode AA129
Newmarket never made diodes as such, but I have seen a welded lead transistor used in this way.
|
25th May 2020, 1:17 pm | #13 |
Nonode
Join Date: Mar 2010
Location: Sunderland, Tyne and Wear, UK.
Posts: 2,476
|
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. |