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Re: Dry Cameras
go to radio shack and buy a cheapie humidity reader . . take out the parts
and you have it :]]]]
On Thu, 11 May 2000, Chris Albertson wrote:
> I asked this question on the list a week or so ago. I wanted
> to know how to measure the dew point. I figured I'd control the cooling
> water temp to a little over the dew point too.
> The answer I got was simply that the dew point equals the wet-bulb
> thermometer reading. (Easy to verify this with a glass thermometer.)
> Just put your standard air temp sensor in a wick over a container of
> water. I think there is a part LMxxx that reads out temp directly.
> > Does anyone know a source for a cheap, not too accurate relative humidity
> > indicator? I would like one powered by 5 or 15 volts, and which puts out
> > only a modest signal. The ADC measurement system has a least significant
> > bit of 300 micro volts. Something with say 3mv or more per % relative
> > humidity would be fine. I think I can tolerate almost any scale factor
> > that such a device would have.
> > I would like to sense the relative humidity. I already sense the
> > temperature. With the two, I think one can compute the dew point. I would
> > then regulate the cooling water just above the dew point.
> > Tom Droege
> Chris Albertson
> firstname.lastname@example.org Voice: 626-351-0089 x17
> Logicon, Pasadena California Fax: 626-351-0699