[RFI] Home Security System RFI

EDWARDS, EDDIE J eedwards@oppd.com
Mon, 4 Nov 2002 09:29:55 -0600


I'd make the alarm company come out and disconnect the power and back-up
battery to determine "for sure" one way orthe other.  Then they'll have
to resolve the noise problem with the mfr for you.  It probably doesn't
meet Part 15 since it causes harmful interference.  Be sure to point
that out.  Also, as said here before, report this info (mfr, model #,
etc.) to ARRL & FCC, and any others that are appropriate.

-----Original Message-----
From: Marc Ornstein
I think I've determined that its coming from my home alarm system.  It
has a
battery backup which would explain why the noise is still there even
with
main power in the house shut down.  When the AC power is shut off, the
alarm
keypad starts blinking all of the indicator lights by design.   When
that
scenario happens, the RFI changes from a rapid pulsing noise to a much
more
noticeable pulsing - and guess what -  the pulses occur in perfect
synchronization with the blinking indicator lights on the keypad.

I've had the alarm co. here and they insist it's not
the alarm system.  I'm pretty sure it is.