Go Down

Topic: transistor switch logic . very hard to solve this scenario. (Read 11857 times) previous topic - next topic


What voltage is your "12V" battery actually providing?


Not enought current maybe. If you take one of them off, does it output the correct voltage?

yes if it has only one regulator the out put had no problem. 7809 = 9 volts.  the same with the other one

but if there is two regulator. the out put will lessen by 2v.

then what about this?
what can you say?


What voltage is your "12V" battery actually providing?

its a motorcycle battery, its 12.5 v in the multitester


Voltage regulators like the 7809 and 7805 require input and output capacitors to prevent device oscillation under some conditions. So check the outputs with a scope if you have one to see if the regulator(s) are oscillating, and if no scope is avalible refer to any datasheet on such regulators and see what the say about recommended capacitors.


Go Up