12 Oct
2024
12 Oct
'24
9:25 p.m.
Didn’t all the IBM mainframes use 400hz? Maybe ask the IBMers how they got 400hz.
Also, can the local power company supply it?
Sent from my iPhone
On Oct 12, 2024, at 14:03, Nigel Johnson Ham via
cctalk <cctalk(a)classiccmp.org> wrote:
Hmm, I think the 40 years has expired, so I can tell the story of the MG at NATO HQ...
It had a two-ton flywheel, and a standby generator off a side shaft that kicked in if
commercial AC failed. Problem was, the building was wired with incorrect phase colouring,
so when they installed it all the motors went backwards! U-Thant got in an elevator for
an upper floor and went down and hit the stops!
On 2024-10-12 15:47, Chuck Guzis via cctalk
wrote:
On 10/12/24 11:54, Brent Hilpert via cctalk wrote:
.
--
Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Skype: TILBURY2591
> Another approach would be to substitute the
old psu by modern ones, possibly by DC-DC converters or switching powersupplies.
>
> Does someone have experience in the substitution of psus in the multiple KW range or
did this in the past?
I recall that one of the benefits of using an MG set (probably better
referred to as a rotary converter, or motor-alternator set) is the
ability to float though short term power glitches.
I remember summer employment at a drive-in movie theater during my
summers working as a projectionist. Power supply for the DC carbon arc
lamps was supplied by a 40 Hp MG set located in its own building. Such
things do generate a fair amount of noise.
Does this date me?
--Chuck