On Thu, 01 November 2001, Kurszewski Chad-WCK005 wrote:
> Mike, that is not correct. A odd-quarter wave
> 75 ohm coax will transform a 33 ohm load up to
> 165 ohms. On the other hand, a 50 ohm line
> will convert 33 ohms up to 75 ohms.
>
> ...
>
> 73,
> Chad WE9V
Duhhhhh!
Chad's right of course.
The 1/4 wave transformers are there to boost the impedance of the
individual elements up to something in the vicinity of 200 ohms
so that when all four elements are feed in parallel there's a reasonable
match to 50 ohms.
So the proper ordering is what was recommended and
what Bill WB0O is using:
element to 50 ohm line to a 1/4 wave of 75 ohm to phase box
73,
Mike K1MK
--
Michael Keane, K1MK
k1mk@alum.mit.edu
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