P3D Re: Flash Circuitry

[michaelk@xxxxxxxxxxx (Michael Kersenbrock)]

> Surprisingly, there is a fairly comprehensive discussion of the
> Vivitar flash circuitry (including the quench tube 292) at:

Thanks for the reference, looks like an interesting site.

However, the Vivitar 292 isn't a quench tube flash.  At 
least not according to my Vivitar manual for it
that talks about its Thyristor circuit "...saves the
excess energy not needed for a proper exposure thereby
providing incredibly fast recycling and a 
greater number of flashes per charge".  It also 
has an IC based "sleep mode" so when it's left
turned on, it doesn't kill the battery.  I've found
the flash left on for days and still running while
my Pentax Flash would have had long dead batteries.
VERY battery efficient flash!  BTW I misspoke about
the guide number, for ASA 100, it's "only" 130.

And no, it's not a "masher style".  It goes on the
hot shoe and can stand vertical or turn 90 degrees.

And in practice, one battery charge *does* seem to
last and last and last.  VERY unlike other flashes
that I've used.  :-)

Mike K.

P.S. - I've used a Flash meter to test it's auto
       exposure, and it does surprisingly well.


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