At 08:35 AM 4/12/98 -0400, you wrote:
>>I want to build an opacity meter to check discoloration in a liquid
solution.
>>New fluid is relatively clear, but as it degrades over time it turns
>darker in
>>varying stages. I thought of using an infrared sender and receiver, but I've
>
>If you are working with nitric acid (sure sounds like it) there are other
>considerations as well.  You would do better with spectral absorption
>analysis.
>
>Let's go private if you are working with acids (my father runs mfg for an
>ultra-pure chem co (Puritan), my brother makes the RFNA for them, and I can
>get the info from them pretty easily - shoot, they might want you to make
>something along the same lines).
>
>Andy

Andy and anyone else who might be able to answer this:

I am just a bit curious as to what kind of light source they use in
spectrophotometers. I have played with one, and it has a rotary dial which
can select any monochromatic wavelength from one end of the visible
spectrum to the other. The whole device was only about 2 feet by 1 foot by
8 inches. Seems like a pretty amazing light source in there! Cost about
$5000, though!

(For anyone not familiar with spectrophotometers, they are devices which
measure the absorbtion/transmission spectrum of a chemical sample)

Sean

+--------------------------------+
| Sean Breheny                   |
| Amateur Radio Callsign: KA3YXM |
| Electrical Engineering Student |
+--------------------------------+
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