Yes, you're right. I didn't notice it at the first glance. Need a cup of black coffee, I guess....You have wired the diode bridge wrongly.
The top wire of the transformer should go between D1 and D3.
Assuming the voltage after the rectifier is 15V. If the output current of 7805 is 800mA, then 10V is dropped across R1 10Ω resistor dissipating 8W. It would be quite hot.or this one the second circuit,. the problem with this is the output voltage in 7812 is 13.88v then drop to 12.55v
i will use this to drive the relay 12v. isn't too risky if the first voltage to go in relay is 13v or 12.5?
http://imageshack.us/photo/my-images/69/96701648.jpg/
by Jake Hertz
by Jake Hertz
by Jake Hertz
by Aaron Carman