Information required for BBC used LL/81 MSC Input Transformer

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sahib

Well-known member
Joined
Aug 19, 2006
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Location
Glasgow - UK
As the title says I would be grateful if someone has the specs for LL/81 MSC Input transformers that I  removed from a BBC broadcast console few years ago. They are 26mm in diameter and 24mm in height with bush mount. Wires are Black, Red, Yellow, Green and Blue.

Mega thanks in advance.
 
Sahib, try measuring the DC reisrtance of the coils in the meantime. The 88's pinout is:

Primary, Yellow (+), Blue (-), White (inter-winding shield)
Secondary, Red (+), Green (-)

You might be able to figure out if they are 600R or 10K transformers for starters. I'll try and look through some old data if I get a chance.
 
Not specific to your type, but this might help to get you a little further, by inference ...

 

Attachments

  • BBC Audio Transformers.pdf
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I have a pair of these LL/81MSC that I bought on Ebay about 18 months ago...

Yellow to Blue: 320 Ohms DCR
Red to Green: 411 Ohms DCR
Black lead appears to be shield

Matches that Canford PDF pretty closely. They are in a Mu Metal can.

Would these be suitable as 10k input transformers?

And Sahib, what console are they from? I can't find any info. And what kind of era.. 70s?

Cheers all!
 
Mega thanks to you all.

I have measured it and indeed the primary is 320DCR and the secondary is 429DCR.

I absolutely do not remember the console. I bought it parted out years ago and just came across the box with the transfromers.



 
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