[Amps] Asynchronous coax matching transformer

Ian White GM3SEK gm3sek at ifwtech.co.uk
Fri Jul 31 23:38:38 PDT 2009


Carl wrote:
>Does anyone remember the formula for matching 50 to 75 Ohms with 2 very
>short lengths of coax?
>If I remember it used a 75 Ohm section at the output of the amp, and a 50
>Ohm section to the CATV hardline. Frequency dependent of course.
>
>Its been about 25 years since I built one.
>

http://www.tuc.nrao.edu/~demerson/twelfth/twelfth.htm

By paralleling two lengths of 50 or 75 ohm line, it can also match to 25 
or 37.5 ohms; or to even lower impedances by paralleling three lengths 
of the same line.


-- 

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek


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