This is a place for the file archives of the Shop-Talk list. I am in no way responsible for the content of the Shop talk list, nor the accuracy of any of these file. If a file here is violating a copyright law, please let me know and I will remove it. This site is based on a "trust fellow shop keepers" basis. Please don't abuse it.
File type:
Diagrams
File description: 6 volt flasher (soild state) Your name: (optional) John Mitchell
File: Click here to d/l...
Connections to the flasher are the same as the mechanical unit: "X" ter-
mainal goes to switched +6V power source, and "L" terminal goes to the
handlebar 3-position signal switch. Note that a connection to ground is
also needed by the flasher. I used a small 3-screw-terminal-strip on the
edge of the small proto board.
One thing to note is that the flasher I built only flashed at about 1/2
the frequency I was expecting. This might be because I used a TI CMOS
555 unit and it may be different than the Motorola or National parts. I
used the Motorola data sheet to calculate the values for Ra, Rb, and C.
To get approx. a 1 second flash rate, I had Rb = 72k and C = 10 uF. Ra
should be kept small to achieve close to a 50% duty cycle. For some rea-
son, I had to go to a 36k resistor for Rb and now I get about a 1 second
flash period. I guess YMMV.
