Power supply problem

I second pichenettes, 7xxxx Series Regulators are either working or dead. My feeling is the Measurements are bad as both Voltages seem to be off but symmetric to GND. Although zenutrio measured a Battery correctly :wink:

@bleo: yes, it’s a bit suspect. zenutrio, have you checked that they are not swapped?


Bleo, that’s embarrasing but true… thank you. In the end it was a stupid error of mine like I suspect in the beginning, thank you for revealing it for real.

And thank you all for your patience, sorry for wasting your time. Next time I’ll check all 3 times before posting… in the succesfully assembled units topic.

No problem! Glad I could actually help! Next thing to check if your voltage tests come back bad is the LT1054. Swapping the 7805 and 7905 can and will fry that little sucker. I just fixed a friend’s Shruthi-1 with this same problem. Hooray for sockets!

Should I be buying a new LT1054 and even replacing the other before having a electrical trouble?

Nah, only replace it if your next set of readings end up like this:

shit happens…

You better replace them with new ones (7805s and 7905s are dead easy to find), and cut the current ones legs to unsolder them easier.
Just to unsolder them, you’re probably going to overheat them and they’ll be no good anyway. Unless you’ve got dedicated tools…

I’ve cut the legs to unsolder them, then cut the legs to make them thiner, solder, and I get the desired voltage values (4’99 and -4’95 to be exact). And yes I was afraid of ruin these guys because they get so hot when tried to desolder them without cutting in the beggining, but they seem to be tough.

Nice! Sounds like you’re ready to roll with the rest of the circuit!

All is well that ends well