[Johnson] Re: GB> RFI

[SBJohnston at aol.com]

Security systems are usually wired with many tens or hundreds of feet of 
unshielded wire to the sensors and the control pads, which act as wonderful 
antennas, but you can usually filter these lines at the point they enter the central 
cabinet.  RFI can happen on the phone line connection as well.  Chokes and 
bypass capcitors should be effective in all these situations.

I recommend the ARRL's online RFI course, see

http://www.arrl.org/cce/courses.html#ec006

and their two main books on the subject:

http://www.arrl.org/catalog/index.php3?category=Interference%2FDF     

Steve WD8DAS


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