[PVRCNC] RF in the shack?

[alsopb]

Guys,

I've been playing around with an oscilloscope here and did some
measurments of the amount of RF one can induce in the shack.

The setup is 36" of wire connected between the hot side of a 1x probe
and ground.  It was placed horizontally on the table.

I hadn't appreciated the magintude of the voltages one could induce.

It turned out that with the quad pointed at the shack and 1500w of
power I could see 5 volts on 20 M!  The quad is 100' distant and fed
with RG-213.  This is probably all direct radiation.  Imagine what
some of the jury-rigged setups with closeby, non-resonant antennas and
a poor RF ground could produce. Turning the loop vertically produced
only 0.1 volt.  The idea to use a vertical antenna for a multiplier
station is indeed a good one.  SO2R might also consider it.  Longer
wires leads are asking for bigger voltages. 

The 2el 40 is over 300' away and it induces 0.2 volts into the same
probe.  That's 72db over a 50 microvolt S9.  You multi-multi's sure
have a challenge.

It is clear at these levels keyers, voice keyers and computers can
easily be clobbered. 

It might also explain why the OM is a bit crazy.

73 de Brian/K3KO