Recent content by bibilit

This is typical from bad caps and low voltage. Check for the 5 volt rail at the HD Molex. Don’t much you can do until caps have not been removed.

Hi, to be honest a $100 was far too expensive, $50 is not the biggest deal of the year but is decent. A mouse is required, but the keyboard is not mandatory and $30 is a fair price.

The Classic is happy with 4,85 volts in the 5 volt rail, below at best zebra bars with the shaky screen. Analog boards are all bad until caps have been replaced (and not only, because those boards are cheaply made)

5 volt rail is a bit low…try to crank it up to 4,8 There is a potentiometer on the side of the AB. Try reflowing the solder joints at the usual places.

I will check voltages, you are getting a clear chime, so not bad, most AB are dead and not delivering any. Can be a bad solder joint, don’t see any hot spot either. But those two RIFA caps should go.

I agree, too far gone, not easy and won’t be cheap if you are not skilled yourself. The other issue is that when the LB is bad with that amount of rust and damage, chances are the floppy and hard drive will be ruined as well.

Hi first, i will clean the board again, i can see a lot of dark spots in the DFAC legs (which is the Sound Chip) flip the card and look for broken traces in the other side of the board.. been there https://68kmla.org/bb/index.php?threads/classic-ii-no-sound…-solved.40921/ if nothing obvious...

Big pads were probably used at the factory for testing purposes, you can skip any work to them. I will try with basic capacitors for tests, then once up and running will go with good ones.

Yes maybe, have you tried the hair dryer trick (heating the capacitors slowly to see if the voltage increase)

I agree, something is written in the black casing, probably a clue here

Probably a broken trace issue in the adb side as the adb connector is just a pass through from one side to another.

is the reset switch doing something ? Can be stuck also.

A lot of rust also in the other side of the board, some legs are rusted in the ROMs area. I will remove everything in a socket for checking purposes.

I see a lot of corrosion on this board, and mainly around the battery. Are you sure this one did not have a leak at some point and the battery wasn't removed and board cleaned quickly ? I will remove the battery holder to have a look below.

Never mind, got it, used an oscilloscope and the right position is not working.