Re: PDP-8/A transformer hum

[Paul Koning via cctalk]

> On Jun 9, 2020, at 10:27 AM, Anders Nelson via cctalk <cctalk@classiccmp.org> 
> 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?
> 
> --
> Anders Nelson

RFI?  Old computers are not well shielded, and putting a switcher into them 
might well create significant radio interference.  It may be ok if the power 
supply is a well shielded subsystem.

Also watch out for minimum load.  Classic power supplies don't mind being 
unloaded; switching supplies often need a minimum load current to keep them 
healthy.  It's probably ok but it is a new consideration.

        paul