On Tue, 23 Oct 2007, Jones Beene wrote: > Last night he took a Luxton light meter and singled > out one LED and took a measurement. He recorded the > reading and then took that same LED from the circuit > and placed a 1K series resistor to it and connected it > to a variable DC supply. He adjusted until the Luxton > read the same, and then recorded the current. Current > was 23.2mA. > > So what is wrong with this?
I was going to suggest exactly this, but I didn't know he had a photometer. I've heard that "RF current meters" are based on the same effect, but instead they use a tiny resistor-pellet with a thermistor-pellet glued to it, all supported on fine wires for thermal isolation. > The low powered AM radio station business nearby is > not a very likely power source. Since his scope measurements don't see AM band stuff, I'd guess that it was some other transmitter. (((((((((((((((((( ( ( ( ( (O) ) ) ) ) ))))))))))))))))))) William J. Beaty SCIENCE HOBBYIST website billb at amasci com http://amasci.com EE/programmer/sci-exhibits amateur science, hobby projects, sci fair Seattle, WA 425-222-5066 unusual phenomena, tesla coils, weird sci
