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47. PURSHASE wireless alarm (pro recommendation).



Be a member of "the" wireless alarm community...

Purchase YOUR wireless alarm system and you will have TWO outcomes:

 OR the system will fail completely during Radio Frequency
    Interferences (RFI) and you will not be aware of it;

 OR you will have nice nightmares coming up if in your wireless
    alarm system there is a RFI detection circuitry as described by
    "SO CALLED" Pro's (without manufacturer data support).

ANYHOW in both cases your system will fail completely with or without
noise and you will have no intruder alarm detection and warning.


What type of signals are able to produce RFI (Radio Frequency
Interference) on Wireless Alarm Systems and will jeopardize they're
operation?
RF Transmitters operating:
- ON the wireless frequency (434 & 868 MHz)
- Falling in the receiver bandpass (sideband rejection is poor)
- Saturating the receiver input stage (wide band in all systems)
- Intermodulation (mix of two signals)
- Harmonics
- On the IF frequency
- and more...
In essence the problems caused by interference is the fact that by no
way two (or more) systems can use simultaneously the same frequency.

 If that famous "undocumented" and "manufacturer unsupported" RFI
detection feature would exist by any chance, be aware that the
wireless RFI alarm night OWL will keep "you and police" awake with
false alarms!
    __________
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   /     /\\\\\//
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     _||_||_

 Paul



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