Adaptor Valve Type 123

[G3PIJpeter]

I cannot find any information about this unit on the internet. The cable has an international octal plug on the end but the pins do not tally with the socket pins on the main panel. Indeed, the socket pins do not tally with each other - including the two identical five-pin sockets.

I doubt it is for the two-panel AVO tester because that already has the sockets fitted to this adaptor. Does the labelling of the sockets P-V refer to specific valves in a specific piece of equipment?

I'm confident that someone out there knows exactly what this is - I'm baffled.

Peter

[M0FYA Andy]

10AD/6 is the Air Ministry Stores Reference number. It is listed in my copy of AP1086 Section 10AD, but the description is less than helpful - "Used on general test gear"

Andy

[G3PIJpeter]

Thanks Andy - with a serial number of 157 plus the description "Used on general test gear" the conclusion is that it is not a one-off and that it had a distinct purpose within the great scheme of things. What sort of "general test gear" would it have been used with? The cable has an octal plug on the end so will only fit an octal socket - possibly to fit a valve tester that does not have an EF50 or British 7-pin base (?)

Also, each of the wires connected to the main cable is colour-coded as it works its way around the valve sockets - eight separate colours all told. However, the wiring does not follow the connections you might expect i.e. all pins 1 connected together; all pins 2 etc. It seems almost random.

I shall photograph the underside and work out what connects to what. It will be interesting to see how the octal socket is wired to the octal plug.

Peter

[roadster541]

Hello Peter!
I am guessing that it was for testing British/European valves on an American valve tester.
Is the Octal socket a Mazda Octal?
73
Rod
M0LXY

[roadster541]

There is probably a logic to the wiring; eg, I would expect pins 3&4 on the B5 socket to be connected to pins 4&5 on the B7, pins 1&9 on the B9G and pins 1&8 on the MO as these are commonly used heater/filament connections for these bases.

[G3PIJpeter]

Originally Posted by roadster541

There is probably a logic to the wiring; eg, I would expect pins 3&4 on the B5 socket to be connected to pins 4&5 on the B7, pins 1&9 on the B9G and pins 1&8 on the MO as these are commonly used heater/filament connections for these bases.

Greetings Rod!

I do not have much knowledge outside octal, UX and B7G etc bases but you seem to be much more familiar with the older B5, B7 etc. I am hoping that you can see some patterns in the following, which I have put together by tracing continuity.

The plug is International Octal 8-pin; the side stud on the plug is connected to the wander lead and clip on the adaptor. The octal plug pins connect to the following coloured wires in the adaptor:

1 = blue
2 = green
3 = white
4 = yellow
5 = red
6 = purple
7 = grey
8 = black

The pins on the plug connect to each of the sockets as follows (socket pins first row; corresponding octal plug pins second row):

P = British 5-pin B5
1 2 3 4 5
3 5 7 2 6

Q = British 7-pin B7
1 2 3 4 5 6 7
4 5 6 7 2 8 3

R = Mazda octal MO8
1 2 3 4 5 6 7 8
7 8 3 4 6 1 5 2

S = ‘P’ type 8SC
1 2 3 4 5 6 7 8
- 7 2 8 6 5 4 3

T = (EF50 base) B9G
1 2 3 4 5 6 7 8 9
2 4 3 6 1 8 5 1 7

U = British 5-pin B5
1 2 3 4 5
4 3 7 2 8

V = (EA50 base) B3G
1 2 3
unclear

It is perhaps significant that the wiring to the two B5 bases is not the same. Can you spot any patterns of common electrode connections? This might then suggest a collection of valve types common to a specific range of (WD?) equipment.

73 - Peter

[Neutrino]

A wanted message on page 19 of the BVWS Bulletin (Volume 8 Number 1) suggests that the Type 123 Ref no. 10 AD/6 is an adaptor for a GEC tube-checker model TC3.

https://www.bvws.org.uk/publications...letin_08_1.pdf

David

[G3PIJpeter]

David

There's not a lot about the TC3 on the internet but the TC3a is in a 1948 document at https://bama.edebris.com/download/ge...GE%20TC-3A.pdf The general principles are on the second page, from which I understand it to not be especially sophisticated.

There's a photo of a TC3 at http://knoppix.net/store/General-Ele...667675475.html While there are single adaptors for extra bases, I cannot see any mention of the Adaptor 123, which is likely, as Roadster suggests, a UK attempt to extend the usefulness of a US tester.

Peter

[M0SOE_Bruce]

Stark Electronic Instruments in Canada built a similar device for their TV-7/DU valve tester giving it an extended capability.

[Ed_Dinning]

Hi , could this have been for use with the US I-177 valve tester?
I think details of this type or adapter were given in that testers operating manual

Ed

[roadster541]

I have compared some valves which I have recently used:
base P: PX4, KT21
base U: MKT4/5
base Q: MKT4/7
base R: VP41
base S: EF8
base T: EF50

The way they are connected to the IO plug means that all of the above valves would work for one setting of the pin selector switches.
IO plug pin connections:
1 screen
2 filament/heater
3 anode
4 grid
5 grid
6 grid
7 filament/heater
8 cathode


I could not make sense of the connections to pins 1 & 2 on the B5 base U,
maybe they have been transposed due to a typo. If they were reversed then that would match the 5 pin base MKT4 and the side contact for the screen grid ties in with the top cap grid connection for the VP41.
This way of connectiong the various bases together makes sense as there would be a lot less selector adjustment between valves than if the pins were wired 1:1, 2:2 etc as in the Stark adaptor.

I am still not sure why two B5 bases, maybe one for directly and the other for indirectly heated cathodes?

I have attached my scribbles!
73
Rod
M0LXY

[G3PIJpeter]

I think that we’ve cracked it.

Post 2: Adaptor Valve Type 123 is listed in AP1086 Section 10AD as ”Used on general test gear”.

Post 4: Guessing that it was for testing British/European valves on an American valve tester.

Post 6: The Type 123 Adaptor socket pins are not wired to the corresponding plug pins.

Post 7: A wanted message on page 19 of the BVWS Bulletin (Volume 8 Number 1) indicates that the Type 123 Ref no. 10 AD/6 is an adaptor for a GEC tube-checker model TC3.

Post 8: Manual for TC3a includes single plug-in adaptors [but socket pins are not wired to the corresponding plug pins].

Post 9: Stark Electronic Instruments in Canada built a similar device for their TV-7/DU valve tester giving it an extended capability – but some of the socket pins are not wired to the corresponding plug pins.

Post 10: A similar arrangement is noted with the US I-177 valve tester.

Post 11: Allocating some common valves to the sockets on the Type 123 Tester confirms that they would work for one setting of the pin selector switches on the main tester.

Conclusion:
1. I possess a valve adaptor for a tester that I do not possess.
2. There is an amazing amount of collective knowledge and experience on this forum.

Action:
Stick with my AVO twin-panel tester for ‘older’ valves and my homemade Radio Constructor ’Dynamic Valve Tester’ for the newer ones (see http://www.r-type.org/articles/art-118.htm ).

P.S. Very happy to post this Adaptor Valve Type 123 to anyone who wants it.

Many thanks to you all for an interesting Easter.

Peter

[M0FYA Andy]

Peter, I would certainly be very interested to buy this item from you. I am interested in anything with an Air Ministry provenance to add to my collection of AM radio and radar equipment and supporting test equipment.

Andy

[G3PIJpeter]

Originally Posted by M0FYA Andy

Peter, I would certainly be very interested to buy this item from you. I am interested in anything with an Air Ministry provenance to add to my collection of AM radio and radar equipment and supporting test equipment. Andy

OK Andy - send me a PM with your postal address and I'll make up a parcel. - Peter

[M0FYA Andy]

PM sent!
Many thanks,
Andy

[M0FYA Andy]

Rather belatedly, I have found a reference in AP2463 which says this Adapter is for use with the I-177 valve tester. Also that AP2537C covers the Adapter. I don't have a copy of AP2537C.

Andy

[G3PIJpeter]

The i-177 adaptor is illustrated here https://www.vanzwamcs.com/greenpages...ter_i-177b.htm and does not look like the Type 123.

Peter

[FrankB]

The U.S. Army also made a "Patch Panel" type external test box for the I177.

I have both the I177 and the "Patch Panel" external box.
Very clumsy attempt, IMHO, to make the I177 "universal".

I suspect the item is quite rare, as I have never seen nor heard of it anywhere.
Great score!

I should add that I had just started to assist Nolan Lee on proof reading his TV10DU setup info. when he passed away very suddenly.
He had published many updated setup guides for U.S. Military tube testers.