Re: Is text available for making an amateur science ultraviolet detector?

Hi James:

I learned some interesting things about UV detectors in this search.  There 
are a couple of companies out there with outstanding detectors.  'Hamamatsu 
Photonics' is usually the first company I go to for photo-detectors.  There 
is another company called 'United Automation' with a series of detectors 
under the 'Sunx' label.  But the detector I chose for you was from 'Laser 
Components'. You can check out their site at the following address: http://www.lasercomponentsusa.com/ifw_jep_5-400.htm

I would use their diode in a circuit similar to the following:


You will need to order such a diode from the company, or one of their 
manufacturer's rep's - you will not find it in a typical electronics store.
Use between 5 to 9Vdc for VCC, set the device in an enclosure, and have 
only a port-hole opening for the detector.  Keep in mind that if you cover 
the port-hole with anything, it may prevent the UV, and may end up 
desensitizing your detector.  Lastly, set both potentiometers to their 
lowest settings, then while exposed to a known source of UV, slowly adjust 
the potentiometers until you get a proper trip threshold and gain 
combination.  If I may suggest, do the following: First nudge up the gain 
potentiometer just a bit only. Then move the threshold potentiometer 
through it's entire cycle.  If nothing happens, then nudge the gain up a 
littel higher, and cycle the threashold potentiometer again, and continue 
until you find the proper trip point.  With this circuit, the sensitivity 
can easily be adjusted by adjusting the gain potentiometer.

Good luck!