Until recently, I was using a remote switch on my tower (it fell a couple of
weeks ago). In looking at a design to replace it, I want to incorporate a
remote switch. Several manufacturers seem to make what appear to be widely
accepted devices. They all have one serious flaw as far as I'm concerned.
1/2 of all the antennas are DC connected at the switch chassis permanently.
On my old system, the box was mounted at 67' or so. A short feedline went
to each of several antennas. In each case, the braid was connected to one
of the elements of the antenna. When you hook them to the switch, they are
all connected together through the chassis of the switch.
On my 40 meter dipole, the RF in the shack was horrible. Think about it. A
40 meter dipole mounted about 1/2 wavelength in the air. One side (the
braid side) is connected to a switch whose chassis is bolted to the
tower--the chassis is 1/2 wavelength from a series of ground rods, 160 meter
radials, etc. Does that make the 68' point a low impedance on 40 meters?
Am I the only one having trouble with remote switches or is it the way I use
them?
The fix in this case was about 20 type 43 beads on the feedline between the
switch and the 40 meter dipole. As far as I'm concerned, this was a patch.
That antenna never played well. The rest of the antennas (yagi, 3 dipoles,
etc.) all had one side connected together through the switch. God only
knows what the pattern really looked like. Sure I could get a good load on
just about any band but God only knows what was really radiating...
What am I missing here? To switch, or not to switch, that is the
question...
Ford-N0FP
ford@cmgate.com
|