[RFI] RFI & Alarm Systems?

KD7JYK DM09 kd7jyk at earthlink.net
Fri Aug 3 20:56:18 PDT 2012

: OK re. the CB-thing, I know others who used to do that in developments
: with garage door openers.

Many of the older ones, especially Telectron (many in my collection) 
operated by a tone on 27.255 MHz, CB channel 23.  With the dramatic increase 
in CB usage beginning in the late 60's, they moved up to 250, 275, 290 

Older Class C paging alarm systems could be triggered at will by either 
recording their transmission or carefully whistling their sequential tone 
code.  Great way to annoy a neighbor at 2 A.M.  You can also whistle various 
tones at an End Of Train Device (replaced cabooses) and get various 

Interesting side note.  The Telectron VHF receiver and small leather-bound 
transmitter, a little smaller than a pack of smokes was used by Mamie 
Eisenhower to summon Secret Service in case of an emergency in the White 


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