David,
Where did you ever hear that antenna manufacturers design their antennas to
match 60-75 Ohms versus 50 Ohms? As an antenna designer, this is a new one
on me. Many years ago in Europe they did some work at 60 and 75 Ohms but I
thought that standard died MANY years ago.
Furthermore, with all the emphasis that Amateurs place on 1:1 VSWR and the
all the 50 Ohm in-line VSWR instruments available, especially the Bird
Thru-line (which is a defacto standard), this sounds really off the wall!
The AEA and MFJ instruments you mention are referenced to 50 Ohms PERIOD.
>I have been told that most beams are designed closer to 65 ohms than 50
>ohms since the 50 ohm standard is not an international standard and that
>other countries use 60, 65, 70, and 75 ohms. This would make 75 ohm cable
>no greater issue for matching than 50.
There is no problem doing what you're doing but most of the antennas I'm
familiar with are matched to 50 Ohms. If your antenna has one of those
jerky Gamma Matches, then maybe it can be retuned to match a 75 Ohm impedance.
73,
Joe, W1JR
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