I was thinking along the lines of Ben's and John's comment, but using a 12v PS, a battery, and a 50 HZ UPS/ BBU.
Old school, low tech, but it works Paul On Wed, Jul 16, 2025 at 2:50 PM Van Snyder via cctalk <[email protected]> wrote: > On Wed, 2025-07-16 at 11:42 -0400, Will Cooke via cctalk wrote: > > > > > > > On 07/16/2025 11:10 AM EDT Tony Duell via cctalk > > > <[email protected]> wrote: > > > > > > > > > On Wed, Jul 16, 2025 at 4:00 PM Jon Elson via cctalk > > > <[email protected]> wrote: > > > > > > > > What I might do is make up a cap bank that is 1.2 X larger > > > > than the 2 uF and power it up. > > > > > > Remember that the resonant frequency goes as 1/sqrt(L*C). So > > > doesn't > > > that mean you want a capacitor of 1.2^2 times the original value? > > > > > > -tony > > > > One thing to keep in mind is that the transformer may not be designed > > to work at 50 Hz. A "normal" transformer will saturate if the > > frequency is too low. A lot of 60Hz equipment won't work (well) on > > 50 Hz unless the transformer is specifically designed for that. > > However, how that applies to a transformer that is already intended > > to saturate I don't know. I do suspect it is still an issue since it > > will likely saturate sooner than expected, for some definition of > > sooner. > > The Computer History Museum in Sunnyvale, CA has a working IBM 1401 > computer from Germany. It has ferroresonant power supplies. They bought > a converter to supply 50 Hz power because they were certain it wouldn't > work at 60 Hz. And it has motors in the card reader, card punch, > printer, and tape drives, that would all run at the wrong speed using > 60 Hz power. > > At first they had an antique and unreliable motor-generator. Now they > have a switching supply that IBM provided (maybe donated). > > > > > Will > >
