[600MRG] Smoke alarm shielding

[sbjohnston at aol.com]

To stop false triggering of household smoke detectors around my house, I've had good luck taking them down and covering the inside of the plastic top and bottom with aluminum foil tape.  They look the same from the outside, but my idea was to create some shielding on the inside to reduce the RF field the circuit board is exposed to - and it has worked in each case.

The tape is purchased at a home improvement or hardware store - probably meant for HVAC work.  

http://www.amazon.com/3M-Foil-Tape-3381-Silver/dp/B00A7I5L86/ref=sr_1_2?ie=UTF8&qid=1414071116

These were all battery-powered alarm units, so they had no connecting wires.  But if they did have power leads or signal lines back to a central alarm panel, I would do the foil tape shielding plus add bypass capacitors to both ends of the runs.

 

 

Steve WD8DAS / WH2XHY

sbjohnston at aol.com
http://www.wd8das.net/
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