I wholeheartedly agree with VZL... the ICE bandpass filters work great.
N5HD and I built a pair of "boxes" with filters for each band and a
relay switching network. 'HD built a little interface box that follows
his '940 for bandchanges. I built a interface box that follows my
Ten-Tec Corsair bandchanges. We use these bpf's for multiop's at K5OJI.
However, since they are rated for only 200 to 300 watts, we use them
between the rigs and the amps.
To give a better picture of how these filters have helped us, imagine a
pair of 70' towers only 40' apart. Now imagine a tribander on each of
the towers at 71', and on one of the towers, a 2 el 40 at 80'. Throw in
a few dipoles for the other bands. Before the filters, the second rig
was useless when the first rig was transmitting. It would practically
jump when the other rig was keyed. With the filters, either rig can be
on any band that the other rig is not on. The ONLY time each rig can
hear the other is at the 2nd harmonic, and even then, it only sounds
like a strong signal.
A funny thing happened during Field Day at K5OJI when I was on 20 cw,
and thought my freq was trying to be taken away. A couple of hundred Hz
below me was a loud station calling cq. It was the 2nd harmonic of our
other rig on 40 cw. Weird being QRM'ed by a station with the same call
as you. A quick shout to the other op to qsy cured the problem, and
kept my 70 q/hr run going.
I have the ICE lpf at home. These things are brutes. I cannot verify
the 5Kw rating. I have opened them up, and they look like they will
take it. This filter has made a big difference in reducing tvi at home,
where I run the Corsair barefoot.
73,
Charlie KD5PJ ocker@dseg1.csc.ti.com
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