Re: Re: [OT] Quick Electronics Question...

["Andy Powell" <ukha@xxxxxxx>]

I was looking at page 2 of the QT113 pdf file, section 1.2

... but I confess I know little about this...

My idea was to use  Ido Bartana's ( http://www.geocities.com/ido_bartana/modifying_hawkey_sensor.htm#Modifying
the MS-12 to be a Door/Window Sensor ) door/window sensor modification to
'activate' and on/off when an object is in proximity giving a wireless
proximity detector - and probably disabling the PIR function on the board
so it didn't send any signals.. that way you could attach it to the
underside of a desk/chair to detect the presence of a person/object...
solving Phil and Jo's problem... I'm sure it could be attached to the
toilet bowl too (at the back so it's invisible). Then a standard MS13 could
be used to do the initial detection (off ignored) and the new, modified
version used for actual presence. I'm sure it could also be used for a bath
too.....

Andy

*********** REPLY SEPARATOR  ***********

On 06/01/02 at 12:42 richard_lockyer wrote:

>Andy
>
>On page 9 of the spec sheet it says that Cs should be 10nF to 500nF
>and Cx should be 0 to 100pF. Which is 1000 times smaller.
>I assume that they are talking about the capacitance of the sensing
>electrode rather than a physical capacitor of that value.
>
>Richad
>
>
>--- In ukha_d@y..., "Andy Powell" <ukha@b...> wrote:
>> Thanks Patrick,
>>
>> They are talking about Cs being 10nF so 20nF should be ok...unless
>of course more really means less if you get my meaning... This
>electronics stuff makes you have to think in a completely different
>way...active-low's when (for me logically) a high would designate
>ON .. but that's just me...
>>
>> Andy
>>
>> >
>> >Usually indicates "_much_ greater than"
>> >
>> >Of course the definition of much is open to interpretation...
mine
>> >(depending on context) is anything from at least double...
through
>an
>> >order of magnitude...
>> >
>> >Patrick
>> >
>>
>>
>> --- Tag-it! v2.0 (c) Andy Powell 1998
>>
>> Apathy is a problem, but who cares?
>
>
>
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--- Tag-it! v2.0 (c) Andy Powell 1998

Ever stop to think. and forget to start again?'