[Antennas] RFI and GFI

2003年2月10日 07:56:45 -0600

Before all that hard work, that is good advice, I would "earth ground" the
radio to the amp to the tuner with the braid from a peice of RG-8. or some
similar copper strap.
At My QTH I solved the same problem by using the aluminum cable scavengered
(salvaged) from a lightning rod system. I still have some trouble on 10
meters, but the other bands are FB at legal limit +. I have a dedicated
220VAC #10 wire electric connection. BUT I am at the opposite end of the
house from the breaker box, so the electric wire runs through the attic the
length of the house to get to my shack. The "Earth Ground" to the radio &
Amp & tuner worked for me.
73, J.
N5QJ
----- Original Message -----
From: "Eric Lemmon" <[email protected]>
To: "Dave Shrader" <[email protected]>
Cc: <[email protected]>
Sent: Saturday, February 08, 2003 3:50 PM
Subject: Re: [Antennas] RFI and GFI
> Dave,
>> You didn't say so, but I assume that your rig is not on the same circuit
> as the bathroom; if it were, almost any RF generator would trip the GFI.
>> Check to see if the bathroom GFI is on a multiwire branch circuit.
> Electricians can, and frequently do, use 14/3 or 12/3 cable to run two
> circuits with a common neutral. The important thing is that the two
> "hot" wires must be on opposite sides (phases) of the 120/240 VAC (in
> condos, often 120/208 VAC) service. If this is the case in your home,
> and your rig is sharing a neutral with the bathroom GFI, you will likely
> trip the GFI.
>> The fix that almost always works for me is to run a dedicated 120 V 20 A
> circuit from the service panel to the shack. The antenna tower or mast
> should have both an RF ground (your radials) and a safety/lightning
> ground per the NEC. The NEC requires an earth ground (rod) at the mast
> or tower, and this ground should be bonded to the service ground. The
> grounding stud on the rig should be connected to the tower ground, to
> ensure that the RF and safety grounds are common.
>> You might also try replacing the GFI that trips with a new one, and not
> the cheapest one you can find. The higher-quality GFI units made these
> days have better RF filtering than those made just five years ago.
>> 73, Eric Lemmon WB6FLY
>> Dave Shrader wrote:
>> > At or above 500 watts on 40 CW the main bathroom GFI trips! [on dashes
> > not dots ...!!]. Obviously, RF on the ground [neutral] wire. The
> > individual GFIs in the 2nd bathroom and outdoor shed do not trip.
> >
>> - - -
>> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
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