Thank you for the detailed information. I need to figure out how im going to get it out of the rack and moved to a place where i can test it over the next couple days where it will not be in the way. Ill find some way to do a dummy load and do an extended test to be sure the supply is working properly. All fingers crossed, god it better not have damaged any of the boards, i do not know where i would get replacements.It took years for me to get the machine, who knows how long it would take to find a specific board that is bad. I did buy an oscillicope and a logic analyzer well in advance in preparation for getting this machine, however short of pressing the power button no clue how to use them or basic troubleshooting procedures. Guess i just have to learn by doing....
On Fri, Jul 17, 2015 at 3:23 PM, tony duell <a...@p850ug1.demon.co.uk> wrote: > > > When I repaired my VT100s I had to replace all the electrolytic caps on > the > > monitor control board to cure the screen wobble. Before doing so I had > > reformed them all and I had tested them all for ESR and they had all > tested > > fine so I was unable to determine which of them was the bad one. Perhaps > > there is other more professional test equipment I could use that would > have > > helped, I don't know. I did keep all the original caps though > (somewhere). > > Are you saying that if you put any of the original capacitors back > (leaving new > ones in all other locations) you get screen wobble. If so, I am not sure I > believe you. It's been some years since I repaired a VT100, but from what I > remember there are plenty of capacitors that simply could not cause > screen wobble no matter what they were doing. > > Or did you recap the board and find that it then worked. In which case (a) > perhaps only one of the capacitors was faulty or (b) it was actually a dry > joint. > > -tony >