I am getting arching in my 80/160 meter vertical switching network. I
have three relays, all run in parallel. The "bottom" of each is attached
to the feed line. All relays are in the open position until energized
and then only one at a time. The "top" of one of the relays goes to the
base of the vertical for 80. The "top" of another relay goes to the base
of the coil and the "top" of the coil is attached to the bottom of the
vertical.
The following suggustion seems to be a very clever solution:
John, W1FV said:
I think I see what the problem is. When you switch in the coil for
160m, the voltage across the coil appears across the contacts for the
80m relay because it's in parallel with the coil.
I avoid that by using a DPDT relay in a "transfer" configuration. The
base of the vertical goes to one pole and the other pole goes to the
feedline center conductor. A jumper runs across the two N.C. contacts
and the loading coil runs across the two N.O. contacts. On 80m the
relay is not energized and the feedline connects directly to the
vertical base through the jumper. When relay is energized to switch to
160m, the poles of the relay connect to each side of the loading coil,
putting the coil in series with the antenna feed. There is no voltage
across the two N.O. contacts for 80m because those two contacts are
jumpered together and are not connected to anything else.
I also have a coil tap for 40. I switch in the tap by means of a second
SPDT relay on the loading coil that selects either the entire coil (for
160) or the tap (for 40).
Does this make sense?
73, John W1FV
I am going to rewire by box this week and report to the reflector. By
the way, many people have told me they have had or are having the same
problem.
Thanks to John and all others who responded...
73,
Bob/AA6VB
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