RFI & modules

[Barry L Klein]

Try using ferrite beads on input and supply lines.  There are
surface-mount parts for boards and donut-shaped ones for TO-8 can leads
etc.  Sometimes you can find a bunch of these on old floppy or hard
drives.
Experiment with the types of opamps you use for input voltage/signal
buffering.  Some rectify RF and others don't.  Try just using a CB
transmitter close to the circuit in question and listening to it with a
known "no-issues" headphone amp or something to debug.  I think the Bi-Fet
types were pretty good at cancelling it... but its been too many years
ago....

If you find a way to make that song go away altogether let me know.... 
God, I hate that.

Barry

----------
From: 	mark scetta[SMTP:n0nspaz at loa.com]
Sent: 	Friday, May 05, 2000 8:51 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