Hi Marv
> I actually had all the relays lined up to do it that way but, I need to
> keep this thing good up at the harmonics and looking at 30MHz, which means
> 90 MHz for the 3rd harmonic, the 10 (10 amp rated) relays, plus their
> interconnects, become a considerable portion (about 3 feet) of the line.
You should be able to find open frame relays larger than 10
amperes that make the connection length about 2 inches total, and
enclosed relays that are half that connection length.
Even if you can't, the length isn't important if you make the
impedance close to 50 ohms.
> If you want to get real fine resolution, you might consider using a
> trombone line, for the last few inches, such as might find in a junked
> HP8741 or similar.
It has to automatically switch to preset positions.
I'll use a stack of preset lumped components (one for each
antenna) to tweek the phase. The bulk of the phase has to use
delay lines.
Tweaking a small amount with a lumped component won't hurt
bandwidth in my application, and it's cheaper and smaller.
73, Tom W8JI
w8ji@contesting.com
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