RFI & modules

[Tim Ressel]

Mark,

Hmmm ... the MOTM stuff is immune, and your homebrews are rectifying...  Sounds
like maybe a ground problem or maybe a high impedance node. First off, how close
is that radio station you're getting? Do have any other items in the house
picking it up?  What we do in these cases is grab some ferrites and place them
on suspect lines. The clamp-on ferrites are easy to work with. The other trick
is to poke around with your finger looking for the spot where the RFI gets
louder. This will sometimes tell you where the offending node is. You can also
try small caps(~100pf) to ground on sensitive nodes.

Let me know how it goes.


Tim Ressel--Compliance Engineer
Hewlett-Packard
Verifone Division
916-630-2541  
tim_r1 at verifone.com                     



-----Original Message-----
From: mark scetta [mailto:n0nspaz at loa.com]
Sent: Friday, May 05, 2000 8:52 AM
To: synth-diy at node12b53.a2000.nl
Subject: RFI & modules


	ok i am tired of hearing "ROXANNE .... you don't have to put on the red 
light...." through my modules. i replaced all audio signal paths with 
belden shielded cable, tying the ground at the jacks but not at the board. 
not helping.

BTW my MOTM modules are fine, it's my DIY stuff that's ailing me....

advice?

mark