Stuart et al
I fully agree and only add one suggestion. When not using the station,
disconnect all antennas and unplug the station.
I have mine on two nice multi plug boxes I made up using a quantity of 4"
square utility boxes each containing 2 duplex 20A receptacles. Unplug 2
cords and everything is disconnected.
73
Bob, K4TAX
----- Original Message -----
From: "Stuart Rohre" <rohre@arlut.utexas.edu>
To: <tentec@contesting.com>
Sent: Thursday, May 17, 2012 5:55 PM
Subject: Re: [TenTec] RFI Issues and other station high voltage precautions
I agree on safety issues with the tuned counterpoise as I prefer to call
it. They are useful to remove RF from the rig metal cabinet. But,
they need to be adjusted for each band in use, they need to have a well
insulated wire and run it outside the shack if possible, so that its end
can be away from the shack. But, you have to protect the end from
accidental contact with anything as you must treat the end as a high
voltage conductor which it becomes when tuned.
Also, be aware, in the case of wind induced static on either an antennas
wire or feed line, that the feeder, even if insulated, may attain a high
voltage that can conduct right thru insulation or such as house wiring
devices stamped 600 volts. Sustained wind charges up a well insulated
dipole or double Zepp to much higher voltages than attained when
running normal RF levels. Thus, insulation suited for 100 watts or 1000
watts may pass current to someone trying to grasp a plug and unplug a
feed line from the station. Disconnect before a storm is within 10
miles. Best, to leave a station's antennas unplugged from the house
entry point except when you intend to operate.
One case of a local ham, was that lightning struck the power line to his
house, then entered his unused VHF rig via the power cord, and exited
partly on the feeder and VHF vertical antenna that was much lower than
the power line coming to the house. Had the rig been unplugged from the
AC outlet, it might not have been damaged, but both it and the antenna
were destroyed along with some house wiring and all his major appliances
that were plugged in, but off or on.
-Stuart Rohre
K5KVH
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|