[CQ-Contest] results auto sw bandpass filters for all bands

Mark Ketchell k5er at arrl.net
Sat Jul 25 23:49:23 EDT 2015

Hi Charly,
      From the two BPFs in my example, you could follow with a simple 
remote A/B switch (Dow-key, etc.). The "A" side from the regular 
bands is normally connected. When a warc band is selected, a diode 
matrix added inside the band decoder could output a  voltage to 
switch the A/B to the "B" side. The common of the A/B goes to one 
input of your SPE. Duplicate for the other radio.

      Unfortunately, this is now many more pieces than your original 
request for a single box. Before I lead you too far down this path, 
you may want to check out the book, "Managing Interstation 
Interference" by George, W2VJN, available from Inrad(.net). May help 
you decide what is most logical for you. Good luck.

Mark, K5ER

>Great suggestion Mark.
>However, where does your RF output from the two filters go?  If directly to
>antennas and antenna switches, ok, but what if one puts a linear amplifier
>to follow the BP filters?
>My SPE amp allows two RF inputs, switchable, so the one input could be
>regular bands and the other input be for WARC.  That could work great.
>But, then where is the OTHER transceiver/amp?  No need for the filters if
>there is no second source of huge levels of RF.  Seems then one would need
>two SPE amps and a second transceiver??
>I thank all with suggestions.  73, Charly

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