Yes, it could very well be. Antennas close (electrically) to transmitting
antenna systems are exposed to large fields and could pickup enough voltage
to damage a sensitive input. It's impossible to say how much without
analyzing or measuring the current levels in the radials and knowing how
far away the BOG is and a million other variables. The safest thing to do
is disconnect the BOG output from the receiver (or short it) when you are
transmitting.
On a related note - do not use anti-parallel diodes as an input clamp
because they will generate harmonics from the transmitted signal. This
isn't a problem unless you are trying to listen on another band while
you're transmitting, such as in a SO2R setup. Use a grain-of-wheat lamp or
one of the front-end protectors.
Other non-bypassed diodes connected to long, unshielded wires, like the
rectifiers in a HyGain rotator control box, will also act as harmonic
generators or mix multiple signals together. A 0.01 uF or similar
capacitor across the diodes will bypass the non-linear junctions. Hams
have a LOT of these diodes in their stations.
73, Ward N0AX
= = = = = = = =
Hey Ward, et al,
This is not related to the original topic but you mentioned BOG antennas
and I have a question.Is installing a BOG near the ground system of an
Inverted-L dangerous for a receiver? Separation between them would be about
1/8 wavelength, perhaps less, from the nearest radial.
In my situation, there would be radials and the BOG(s) in the same body of
water. I have no clue how much RF current and voltage would be in there.
Thanks, Joe, K8MP
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