• Hello, Guest! Welcome back, and be sure to check out this post for more info about the recent service interruption and migration.

Yet Another LC PSU thread - How to test with a multi-meter?

reallyrandy

Well-known member
I have a TDK and an Astec PSU for my 2 LCIIs. Both are completely dead. I could just re-cap and hope for the best but Id' like some guidance on testing voltages with a multi-meter. How can I tell what the voltages are coming out of the PSU?

Also, I have lots of hardware reference books but none go in-depth with the LCII, are there any out there?
 

Nixontheknight

Well-known member
It should say which voltages are supposed to come out of which pins on the logic board, hook it up to a known working LC logic board that you don't care about, flick on the supply, and check the voltages, comparing to what they are marked as on the board.
 

reallyrandy

Well-known member
It should say which voltages are supposed to come out of which pins on the logic board, hook it up to a known working LC logic board that you don't care about, flick on the supply, and check the voltages, comparing to what they are marked as on the board.
Unfortunately, I care about all of them. Is there no way to test directly from the pins on the psu molex?
 

cheesestraws

Well-known member
You should be able to get an idea whether anything is dangerously over without the PSU plugged into a board. Note that its outputs will be a bit off without a load, but you'll probably be able to tell if it's way off.
 

reallyrandy

Well-known member
You should be able to get an idea whether anything is dangerously over without the PSU plugged into a board. Note that its outputs will be a bit off without a load, but you'll probably be able to tell if it's way off.
How can I tell that? What I'm after is what pins should I put the multimeter on?
 
Top