On 2020-06-09 10:27 a.m., Anders Nelson via cctalk wrote: > Related question: Is there any reason, other than historical accuracy and > cost, to not replace the power supplies in vintage computers with modern > switching power supplies? >
3) If it ain't broke, don't fix it > -- > Anders Nelson > > > On Tue, Jun 9, 2020 at 10:19 AM Paul Koning via cctalk < > [email protected]> wrote: > >> >> >>> On Jun 9, 2020, at 2:59 AM, Josh Dersch via cctalk < >> [email protected]> wrote: >>> >>> Hi all -- >>> >>> I'm working on a PDP-8/A I picked up at VCF West last summer. After a >> lot >>> of cleaning and some power supply repair it's showing signs of life (CPU >>> seems to be at least minimally functional, core memory is going to need >>> some debugging.) >>> >>> The transformer in the power supply is humming quite loudly, however, and >>> I'm curious if this is normal for the 8/A (or is typical for an 8/A of >> this >>> vintage). I'm used to the supplies in various other DEC machines not >> being >>> exactly silent but this is a rather severe 60Hz buzz that you can clearly >>> hear over the fans when the machine is in operation. >> >> Assuming these are traditional transformers with laminated sheet iron >> cores, check if the rivets or screws holding the laminations together are >> loose. If yes, tighten or replace the fastener. >> >> paul >> >>
