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Old March 1st 09, 07:58 AM posted to rec.radio.amateur.antenna
Sal M. Onella Sal M. Onella is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 442
Default Whats a Good Source for Ferrite Donuts


"dave" wrote in message
m...
Sal M. Onella wrote:

I just did a fix with one donut for RF getting into my computer keyboard

on
PSK31.


How much power do you use for psk31?


I generally set it for about 50 watts to get a decent fade margin. With
good propagation, I've used as little as 15 watts and had a solid QSO. (I
retweak it for each QSO, since the equalization of the audio input isn't
flat. 1500 Hz audio might give me 50 watts, but if I click at 800 Hz, I
might get 15 W. The rig has an equalizer in it. Ya think maybe I should
learn to use it?)

I put a newer computer in service for PSK and I found that at 50 watts I was
getting doubles and triples of many of my keystrokes during QSOs. When I
dialed the power down to 25 watts, the problem went away. Ferrite time.

Funny, with the old computer (a 486 running Win95) the RF got into the mouse
only. With the new XP computer, the RF got into the keyboard only. Go
figure.