[sci.electronics] Burglar alarm on an electronic thermometer.

maddog@oneb.wimsey.bc.ca (04/09/91)

QUESTION - How does it work ?

PROBLEM  - We recently obtained the IVAC Temp-Plus II electronic
           thermometers.
           They have an alarm which sounds off if the thermometer
           is not returned to its wall mounted case within one
           hour of a previously set time period.Its function is 
           also crippled at this point in time.
           There appear to be no external connections between the 
           thermometer and the case.
           I can see in the base of the case what appears to be
           a 2 cm long piece of metal embedded in the plastic.
QUESTION - Could there be some sort of magnetic induction switch 
           functioning here ?

Thanks from the curious but ignorant.

hbg6@citek.mcdphx.mot.com (04/09/91)

In article <g3k4Z3w163w@oneb.wimsey.bc.ca> maddog@oneb.wimsey.bc.ca writes:
>           a 2 cm long piece of metal embedded in the plastic.
>QUESTION - Could there be some sort of magnetic induction switch 
>           functioning here ?

I have seen a hand-held meter that had a drop-in recharger that had no
electrical connections. Essentially there is a transformer with the
primary in the base and the secondary in the hand-held portion.

John

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Have fun, Play nice, Don't fight.                             OK Dad.
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John Schuch - Motorola Inc., Computer Systems Division (602)438-3008
All opinions expressed are mine and not Motorolas,        their loss.
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