20 Jan
2012
20 Jan
'12
1:47 p.m.
Ian was not at LCM yet when we did exactly this, after
reading the CDE
white paper. More than 95% of the aluminum electrolytic caps in the 2065
had failed. We first tried "re-forming" a few. They failed again in
days.
I was under the impression tha the oxide dielectric film was originally
produced by a process that's much the same as the reforming process. So I
wonder why the reformed capactiros didn't last. Was theres somethign else
wrogn with them?
At that point we made the decision never to waste our time on this. We
buy new capacitors (or higher-level components; cf. our PDP-7) and put
them in.
AS somebody who. like you, wants to run their classic computers, I must
admit that I also replace defective capacitors. I use the neares new
equivalents that I can find (same or a little hight capacitance, same or
a bit hight working voltage). The appearance foesn't matter too much to
me. I simply think 'what would have been don e if this capacitor had
failed when the machine was in 'serious' use' -- and the answer is 'It
would have been replaced by a suitable new part'.
Perhaps I've been lucky, but I've not found that electrolytiics are the
problem that soem make out. As I said the other doay, I've replaced
perhaps 10 of them in all my old machines.
-tony