On 7/14/97 2:31 PM, Doug Westover at westover@sneezy.sri.com wrote:
>I've got a DEC VT-220 'dumb terminal' that I use on packet that throws
>out crap all over the 20 meter band (in fact that seems to be the ONLY
>band that's a problem).
I have a WYSE 85 terminal that caused similar trouble. (Ironically, the
85 is a VT220 clone -- perhaps in more ways than one)
>I've tried ferrites on the keyboard cable, the
>power cord and the serial cable to the TNC, all to no avail.
I discovered that a goodly portion of the RFI from the WYSE was from the
keyboard. By disconnecting the keyboard cable, most of the RFI went away.
>The next
>step, I guess, is trying to shield the cabinet interior. Does anyone
>have any feeling how good the shielding spray 'gunk' is? Or should I
>try to kludge something together with aluminum foil or copper sheet.
I used a can of that spray "gunk" on the inside of the WYSE. It helped. I
also grounded the terminal to the station ground. That helped. The
keyboard problem was cured by placing a ferrite bar in the coils of the
keyboard cable.
Most of my RFI was in the 10m band.
Eventually, I replaced the WYSE with a Mac. That REALLY helped.
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@radio.org
Quote: "Not in a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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