system@sys6626.bison.mb.ca (Victor Spicer ) (04/06/91)
I designed an electronic "alpha-inducer" LED flashing circuit which works very well. It uses a chip designed for flashing LED's, the 8 pin LM 3909. Connections are as follows: Pin Connection 1 NC 2 + of 100uf electrolytic 3 NC 4 wiper tap of 100k pot, gnd 5 + 3 volts 6 + LED connection 7 NC 8 - of 100uf electrolytic other connection on 100k pot Power is provided by 2 alkaline D cells, which can keep the unit running for several months of continous use. The D cells are necessary to provide sufficient current to the LED's. Frequency range is about 1 Hz to 40 Hz. LED's are looked in parallel and epoxied into holes drilled in a pair of sun glasses. The highest intensity LED's that can be found are best. The unit is best used in a darkened room, with your eyes closed. Experiments with this unit have revealed some interesting results. At higher frequencies, your eyelids start twitching in sync with the flashes. It can be used in conjunction with a GSR device (the one Radio Shack sells works very nicely). It also does a good job of freaking out guests who wonder what the basement full of electronic widgets is about.... :-) .... victor spicer sysop system 6626 63 point west drive winnipeg manitoba canada INTERNET: vspicer@ccu.umanitoba.ca OR system%sys6626.bison.mb.ca@niven.cc.umanitoba.ca MB-Net: system@sys6626.bison.mb.ca UUCP: niven.cc.umanitoba.ca!bison!sys6626!system