Mike,
It's virtually impossible to evaluate your problem from the description
of
your hookup. It is very possible that you are suffering from common mode
RFI. I would do some experimenting with the ground system to see if I
could minimize the paths. I had to abandon my "single point ground" and
bond the interstation bus to ground rods behind each operating position,
Others have had good results by using ground isolators on all of their
incoming RF lines.
I will probably get a lot of flack about my comment on single point
ground,
but just keep in mind that when using modern day equipment, there is no such
thing. Where do you think that green wire goes?. For a quick test, ground
the
receive antenna on your test radio and see if you don't get really loud
harmonics.
73 and good luck,
Dallas W3PP
Subject: [CQ-Contest] Testing Stubs
> I have just recently tried using the Top Ten stub box (double stub) and my
> own homebrew stubs (and stub switching box) on my main CQ radio and am
> puzzled by the ineffectiveness of both. I obviously must be doing
something
> wrong but can't figure it out.
>
> The set up is radio-ICE 419-amplifier-LPF-wattermeter/sensor-stub
> box-wattmeter-WX0B 6 pack box-manual antenna switches -antennas. I also
> have a 419 in the receive loop on the second radio.
>
> The LPF and wattmeter/sensor are connected to amp using right angle
> connectors and the stub box using 10' of supplied RG-214.
>
> The test setup is transmitting on 3510, 7010 or 14010 and listening on the
> 2nd, 3rd, etc., harmonic on the second radio. 20 and main 40 meter
antennas
> are on the same tower but all the other combinations are on different
> towers. What I am finding with this setup is no change in s meter
reading
> on the second radio listening on the harmonics when I switch the stub box
> in/out.
>
> Thanks,
>
> Mike W9RE
>
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