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DIM-BRIGHT LIGHT

Parts list: 1-(220 mf capacitor)/1-(47 mf capacitor)/1-(22 ohm resistor) 1-(3904 transistor)/1-(3906 transistor)/1-(3909 IC)

This circuit has the effect of producing a dim bulb output with an intermitent bright output corresponding to the 55-60 rpms of a gyra.

It works on 1.8 volts. It looks dim at 1.5.

Eliminating the 22 ohm resistor makes the light flash on and completely off. It could be used as an end of train device.

If using an adjustable voltage regulator to power this device, an RB resistor value of 69 ohms will work (47 ohms + 22 ohms in series).