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FS: Massive General Radio Input Transformer Type 641-401

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Murdock

Well-known member
Joined
Jan 28, 2015
Messages
930
Location
Germany
Hey folks,

selling a big rare transformer from General Radio. Type 641-401.
It has a diameter of approx. 75mm and is approx. 102mm high.
Resistance values ​​are around 450 ohms on one side and around 9k (9000) ohms on the other.
It also has a shield.
There is little information about this transformer on the net.
It was installed in the General Radio "Distortion and Noise Meter Type 1932" as an input transformer.
There is a circuit diagram on the net.
According to the "Type 1932" manual, this transformer can handle levels of up to + 32dBu.
There is also information on the net about the "Type 641" transformer series.

Asking 60,- Euros plus shipping.

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Cool transformer.  Much like a UTC LS-26, 600Ω bridging (10KΩ) to tube grid (100Kish).  Great for a line amp or compressor input.
 
EmRR said:
Cool transformer.  Much like a UTC LS-26, 600Ω bridging (10KΩ) to tube grid (100Kish).  Great for a line amp or compressor input.

It is a really nice transformer.
But I don't think it is like an UTC LS-26. As the ratio is only 1:2 I think. Maybe a 10k:40k transformer?

Added some pictures  ;)
 
5k:50k, 10k:40k, comes out in the wash, esp in the applications.    I assumed 100k from schematic, looked like a place they’d go for matched condition. 

 
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