Forever Clock
24/7 running digital clock, no battery ever needed.
This clock normally sits on my workbench and has been running for about a week now using just ambient daylight.
The Polyacene cell charges up in the day and runs the clock overnight. Doesn’t matter if the sun doesn’t shine, a cloudy day is fine.
The circuit is a furtherment of a successful Forever Light, which has been running all the time since mid January…I wondered what else such a thing could power instead of an LED.
Polyacene cells can be purchased at Electronic Goldmine, 5 for $1.
http://www.goldmine-elec-products.com/prodinfo.asp?number=G13133
They are a supercap rather than battery, that will discharge over a few days to zero if not topped up.
The L1/L2 are 120 turns each. Wind 120 turns onto the ferrite core, twizzle a small section and carry on with another 120 turns. The twizzled join forms the Positive connection in the circuit. A 1:1 winding.
Many types of small signal diode can be used, a germanium type would drop less to the polyacene cell, but a 1N4148 or equiv works fine.