400Hz supplies; was: RK05 spindle pulleys - trade 50Hz vs 60Hz?

[Tony Duell]

On Thu, Jul 26, 2018 at 5:28 PM, Chuck Guzis via cctalk
<cctalk at classiccmp.org> wrote:
> On 07/26/2018 08:26 AM, Tony Duell wrote:
>
>> I believe if you want to be pedantic that a motor-generator set is a motor
>> (with an armature/rotor and a field/stator) mechanically coupled to a
>> generator (with its own armature/rotor and field/stator) whereas a
>> dynamotor has a common field/stator (and possibly both armature
>> windings have to be wound on the same core).
>
> Hence my term "unitized", which I thought to give the basic idea without
> going into excessive detail on an obsolete device.

This is classiccmp. We 'do' obsolete devices here :-)

>
> In connection with similar low-power high-voltage supplies, I could also
> have mentioned vibrator-transformer supplies, run from DC battery, used
> very often in lower-power tube gear, such as auto radios and even photo
> strobe flash.

Indeed. I've never seen a photoflash using such a supply, but I have read
about them. One day I'll add one to my collection.

They were commonly used in car radios over here too.


>
> The high-voltage DC was obtained from the transformer secondary by
> either a traditional tube (very often cold cathode gas) rectifier, later

0Z4 IiIRC wa a common rectifier valve.

> solid-state (selenium or silicon) or an additional set of contacts on
> the vibrator itself.  Notorious for kicking up all sorts of RF noise.

The latter was known as a 'synchronous vibrator' (at least over here)
as the 2 sets of contacts were synchronised to (a) apply a pulse to one
end of the primary winding and (b) select the appropriate end of
the secondary which will have an high voltage pulse of the correct
polarity.

A mad friend of mine commented that a google search for a spare
part for his car radio directed him to an awful lot of 'adult' sites...

-tony