On the ground, I have to agree. At my other QTH I had a very good ground system (8 foot
ground rod 6 feet of #8 wire)& had more problems getting into the phones, cable TV,
& I can't count the times that during a storm I would have lighting come in on the
coax to the tuner which was grounded.
There are different kinds of ground systems for different purposes. For
the purpose of keeping RF potential at the rig low, a good way to go is
to have a quarter wavelength piece of wire connected to to ground
terminal at the back of the radio, with the other end not connected to
anything. The wire should be stretched straight as much as possible,
though if it has to go around a few corners that is no problem. I
suggest one or more of these wires for each band. Since you are only
having what may be an RF problem on a couple of bands, you might want to
try just a couple of wires for these bands. You can use 234/f (f in MHz)
to calculate the length (in feet) of the wires. It would be safest to
have the open ends of the wire either made into loops, or soldered to
rings of some larger diameter wire, to reduce the possibility of corona
discharge. Just don't have sharp pointy ends of these wires in the
drapes or under the carpet.
I used a system like this when I lived in a second floor apartment. I
had "Eye" lugs on each wire, and stacked them up on the grounding stud
on the back of my TS-440 until no more would fit. I used 14 AWG stranded
copper insulated (THHN or THWN I guess). I just laid the wires on the
floor, along the baseboards. I didn't bother with anti corona measures,
and running at 100 watts I didn't catch the building on fire even once.
Without this system I had RF feedback on some bands, and got RF burns
sometimes when touching the autotune button. After I put this ground
system in, all of those problems went away. This kind of system will not
protect you from equipment faults that cause a hot chassis, nor will it
protect from lightning.
DE N6KB
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