[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.


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

More information about the Amps mailing list