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Old April 21st 06, 08:38 PM posted to rec.radio.amateur.homebrew
- exray -
 
Posts: n/a
Default HB VHF low-pass filter

K7ITM wrote:

I question the bit about insertion loss 7MHz away being a non-issue
with only a single open stub across the line. If you put an open stub
of lossless 50 ohm line a quarter-wave long at 153MHz across the feed
line, it puts a short across the line at 153, but it puts 0.26-j3.58
ohms across it at 146MHz. That's a 99% reflection, or SWR close to
200:1 at 146. It's only about a 17dB loss, but that's more loss than
I'd want.


You're correct. Someone pointed this out to me via email so I'll
retract my recommendation of using the stub.

Thanks,
Bill