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From: durham@w2xo.pgh.pa.us (Jim Durham)
Newsgroups: rec.radio.amateur.misc,sci.electronics
Subject: Re: Conductive paint question
Keywords: Conductive paint, RFI from computers
Message-ID: <168@w2xo.pgh.pa.us>
Date: 25 Jun 91 16:08:35 GMT
References: <762@eskimo.celestial.com>
Reply-To: durham@w2xo.pgh.pa.us (Jim Durham)
Organization: Jim's Basement, Gibsonia, PA
Lines: 29

In article <762@eskimo.celestial.com> mann@eskimo.celestial.com (Tom Mann) writes:
(stuff deleted)
>my transceiver   - and there's the rub. All of my computer/terminal
>stuff throws so much RFI garbage that my receiver is nearly useless.
>I've already installed toroids on the power leads, cleaned up the
>shielding and improved my grounds ... all with marginal success.
>
>What I'm looking for now is the next level of suppression. Do conductive
>spray paints work? If so, any particular brands and where can I find

I suggest this test: Remove the coax from the back of the "rig". Terminate
the coax connector with a plug and 50 ohm resistor. If the RFI is still
there, you need shielding. If not, you probably need to move or
improve your antenna system. 

I moved my dipole farther away from the house. This helped a lot until
the balun failed and I removed it. "Who the heck needs a balun?"
Without starting a "balun vs no-balun" war, removal of the balun
on my dipole made it impossible to operate. That's quite a difference.
Feedline unbalance made the coax, which was much closer to the
noisy computer equipment act like an antenna and pick up the birdies
(Long explanation omitted).
(Balun Haters..cool it..I ended up with a tuner out under the antenna).

I would try this before spray-painting your equipment. Remember the
plastic panels!

Good Luck
Jim Durham  W2XO