Re: LEDs for Focault Testers

SCN User (notpete@scn.org)
Wed, 19 Apr 1995 22:34:02 -0700

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>
>I've noticed that several people recommend using LEDs (green) for their
>light source in a Focault tester over a bulb. What is its advantage over
>a small bulb? Why use an LED? Thanks for your patience.
>
>-- Rob O.
>
I started using an LED because the bulbs I used didn't last long in the confines of my tester. At first I used a red one, but it was hard to see. The green one works well, isn't hot and has lasted many years. I'm surprised it has lasted since I run it at about 4 times its rated current. For testing long radius mirrors (tri-schief tertiary) I use a halogen flashlight bulb.

Peter

--
 Peter Hirtle   notpete@scn.org   Seattle, WA.

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