Hello all
I have now managed to "brick" two analog boards in the process of doing recaps. I've had good luck with all my other recaps but these seem jinxed. The first came up properly (logic board and hard drive) but I had forgotten to connect the high tension led to the CRT. This bodged something and has prevented it from coming up since then (won't even turn on, so assume it's in a safety shutdown mode)
The second, the above's replacement, was working fine but "needed" recap so that was done, but lot's of time passed between removing the old caps, then installing the new. In the meantime my geezer brain took another cognition step function downward and I installed all electrolytics in backwards. No go at power up, at which I quickly realized what I'd done, ordered another set, and did it all again. Again no go at power up. None of the 'lytics showed any signs of stress at being in backwards which I attribute to very little power getting onto the board.
So, I'm tempted to go begging for yet another analog board. But, I have a 'scope and good DMM and would like to give troubleshooting a shot. Problem is I have not been able to find any kind of schematic for these things. Secondly, you have to do all the poking around with the board fully installed, which makes getting access to test points pretty difficult
Has anyone ever attempted fixing one of these? Is there any possibility schematics exist somewhere I haven't looked? Any insight would be greatly appreciated
Charlie
I have now managed to "brick" two analog boards in the process of doing recaps. I've had good luck with all my other recaps but these seem jinxed. The first came up properly (logic board and hard drive) but I had forgotten to connect the high tension led to the CRT. This bodged something and has prevented it from coming up since then (won't even turn on, so assume it's in a safety shutdown mode)
The second, the above's replacement, was working fine but "needed" recap so that was done, but lot's of time passed between removing the old caps, then installing the new. In the meantime my geezer brain took another cognition step function downward and I installed all electrolytics in backwards. No go at power up, at which I quickly realized what I'd done, ordered another set, and did it all again. Again no go at power up. None of the 'lytics showed any signs of stress at being in backwards which I attribute to very little power getting onto the board.
So, I'm tempted to go begging for yet another analog board. But, I have a 'scope and good DMM and would like to give troubleshooting a shot. Problem is I have not been able to find any kind of schematic for these things. Secondly, you have to do all the poking around with the board fully installed, which makes getting access to test points pretty difficult
Has anyone ever attempted fixing one of these? Is there any possibility schematics exist somewhere I haven't looked? Any insight would be greatly appreciated
Charlie