www.piclist.com/techref/microchip/devices.htm?key=pic

Mark wrote:

....

>>

>> Plus, I suspect you could use 2 or more thermistors arranged

>> vertically within the tube, plus a little math, to actually

>> determine the level, not just whether above/below one point.

>

>True on multiple height determination - though (despite my being pretty

>good in math) I don't see where the math's needed/applicable. I thought

>with 3 hot beads, you'd know one of 4 states, {"Height < A" || "Height

>>= A" || "Height >= B" || "Height >= C"}, don't see how you can determine

shades of height between say A and B (putting A lowest, C highest here, to

clarify.) Am I missing something? Has been a "Bad Brain Day" to some

degree <G> (There's not a big difference for thermistor B in temperature,

between temperature for water say 1 foot below it and 1 inch below it,

barring splashing, is there? Has been a while since I last hot-beaded <G>)

>

Not that I've ever tried this, but I figure the temperature variation

would distribute itself along the tube in some manner [to be measured

and calibrated empirically], and the math would be some weighted

averaging routine. Just a thought. The sorta thing you try once, and

immediately get a strong hunch whether it will ever work or not.

- Dan

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