Piers wrote: >> when a DC power source is available, it is converted (inverted)
by the flash circuitry to AC using an oscillator (which whines) EVEN IF there
is also mains AC power ...
Tim Hughes, are you there? <<
Yes, the external high voltage power source just runs in parrallel with the
internal high voltage invertor source output, if there are batteries in the
flash. Diodes isolate the two sources from one another and the outside world.
The auto flash - light integrator runs off a regulated section of the high
voltage, using a weird circuit trick common to many flashes, after the flash is
triggered. It does not run off the unregulated battery.
Regards,
Tim Hughes
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|