[AMRadio] Unusual transformer

Robert Nickels ranickel at comcast.net
Sun Oct 22 12:26:53 EDT 2017

On 10/22/2017 10:52 AM, Donald Chester wrote:
> Looks like it's a modulation transformer designed to be fed with a 500-ohm line, instead of directly by the plates of the modulator tubes.
Ah!  I think you're right, Don - especially makes sense because it was 
part of a bunch of iron that came from a guy who built broadcast 
transmitters back in the 30s when it was legal to do that, as well as 
ham transmitters.
> 5M-6M-7M-8M-9M-10M means the same thing as 5K-6K-7K..., i.e. 5000, 6000, 7000 etc. "M" is sometimes used as an abbreviation for "mill" = thousand.

That abbreviation skipped right over me, but yes, "mill" was used before 
the now-ubiquitous "K".

So, a useful transformer, especially if an old PA amp or such was rigged 
to provide the 500 ohm drive.

Mystery solved, thanks!

73, Bob W9RAN

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