Quote Originally Posted by AvionicsMaster1 View Post
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I hooked up the circuit to 4 x 1.5AA batteries through a TO-92 5V regulator
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At best this configuration can provide 6 volts to the voltage regulator.


Quote Originally Posted by AvionicsMaster1 View Post
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I couldn't find a 78L05ABZ in their symbols library
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http://pdf1.alldatasheet.com/datashe...8L05ABZAP.html

This voltage regulator has a voltage drop-off of 1.7 volts:

6Vin - 1.7Vdo = 4.3Vout

At full charge, the best you can get is 4.3 volts; things can only degrade as the batteries weaken.

Try adding an extra battery (5 x 1.5).

7.5Vin - 1.7Vdo = 5.8Vout

7.5 input volts is not going to put the voltage regulator in danger.