[TenTec] TenTec Digest, Vol 46, Issue 64

[Art]

John,
In addition to the other suggestions let me add there is no guarantee 
which cable the RF gets into your computer on. You might have to filter 
them all. The split cores are really handy and don't cost $9 a copy. For 
sure start with the power cord. If it was me I'd do the offending 
keyboard cable at the same time. Since it's 80 it might take more than 
one core.

You didn't mention grounding. I found it necessary to include the 
computer case in my station grounding setup. Not only did it reduce rfi 
into the computer, it also reduced PC noise in the receiver. All chassis 
go to a single common ground point, then outside to copperclad steel 
rods. Since your shack is on floor2, you'll need a wide strap for a 
ground bus to keep the L down.

It's normal to have a whole new experience on each band you have RFI. It 
all depends on how friendly the RF path into your gear is.

Best wishes. If it was easy, nobody'd have RFI!
73 Art

tentec-request at contesting.com wrote:

Message: 8
Date: Thu, 26 Oct 2006 09:56:03 -0400
From: "John K Gotwals" <john at gotwals.com>
Subject: [TenTec] RF gets into computer
To: <tentec at contesting.com>
Message-ID: <004001c6f906$7f0a0180$0300a8c0 at john>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
	reply-type=original

When I operate on 75 meter SSB with my Orion, my computer beeps and 
disconnects/reconnects my USB connected keyboard. Note that I do not have 
this problem on 40 meter SSB. My computer is located on the second floor of 
a brick house, and one end of my dipole is about 15 feet from my shack.

>From comments made by others on this list, I may have to put RF filters on 
the cables and wires connected to my computer. I am contemplating the use of 
Amidon FT-240-77 ferrite toroids, which have an I.D. of 1.4 inches and cost 
$9 each. If I buy in quantities of 10, is there a cheaper source for this 
toroid?

Any comments or suggestions on this problem would be appreciated.