Hey Guys'
Why don't you Just post a diagram with the pertinant information on on the RB
site. A picture is with a a thousand words.( and numerous back and forth
emails) I would be interested in seeing a simple solution for a new harness
for all the DB di-pole antennas using commonly available cable and components.
My 2 cents worth on the subject.
--
Doug
N3DAB/WPRX486/WPJL709
---- Jeff DePolo <[EMAIL PROTECTED]> wrote:
=============
> What this does with antenna element at 50 Ohms then 1/4 wl
> down the 35 Ohm cable it looks close to 100 Ohms looking into
> this cable.
No, that's not right. If the element were 50 ohms and you attached 1/4 wave
of 35 ohm cable, you would transform it down to 25 ohms, not up to 100 ohms.
You could transform 50 UP to 100 via a 75 ohm odd-quarterwave cable.
> The length of the 50 Ohm coax going from the tx/rx to this
> antenna input does not matter for SWR or impedance. Only
> concern would be length and loss of 50 Ohm cable.
Just to be clear, the length of the 50 ohm cable doesn't matter at the input
to the antenna, but it DOES matter within the harness itself even if the
cable isn't being used as a transformer. The bays have to be fed in-phase
otherwise uptilt/downtilt and elevation pattern distortion will occur.
--- Jeff WN3A
