Subj : Re: Powering up 28s and 64s that have been in storage for at least a de To : Kenzo From : Computer Nerd Kev Date : Fri Apr 29 2022 09:06 am Kenzo wrote: > > For the 128 and 64 computers, should I power them up with low > voltage on a variac for a while before giving them the full 120v? > The idea being to perhaps give the old caps a better chance of > surviving powerup after long storage? > > Or would low voltage give the power supplies and internals problems? It should be OK so long as you don't connect any externally-powered accessories such as a disk drive when they're under test, in which case the voltage difference between the different devices could cause damage in various ways. Usually that technique is used with equipment with higher internal voltages though, I'm not sure whether it will prevent much in this case where the difference is only a handful of volts. > I will have a dim bulb tester in series also in case their are > any serious problems with the units. That should only be needed for the power supplies themselves, as the voltage regulator inside the PSU should limit the current to the computer if something inside draws way too much power. Furthermore I'd suggest you check the PSUs separately from the computers, and always test the computers with a known good PSU. -- __ __ #_ < |\| |< _# --- SoupGate-Win32 v1.05 * Origin: Agency HUB, Dunedin - New Zealand | Fido<>Usenet Gateway (3:770/3) .