When you use solar cell will meet a problem voltage do not be stable. Then must use regulator circuit. We try to come to see shunt regulator circuit the this. Type time merit be use good easy this circuit uses pillar equipment is IC [...]

A car voltage general is 12 Volts. How about when you want to connect non 12 volts devices into your car? The circuit here is the solution. Even the circuit is design for a car apppliance, it does not seem it can’t be used for another purpose.
source: http://www.geocities.com/dsaproject/electronics/
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According to from this circuit 12Vdc to 9V DC converter step down voltage by LM317T give current a little go to. We come to see the way enhances current better follow circuit picture enhance Transister TIP2955 or MJ2955 down go to help give current increase follow [...]