The guy with the flash camera idea is on track. Audio Express Magazine had
a writeup on them a few months ago, as did Nuts and Volts some years back.
I reverse engr'd a Fuji camera and it's just like the AE Mag circuit.

Circa 1976, I made a simple two transistor oscillator, which ran off a 1.5
volt battery that connected across a reversed filament transformer, lite a
neon bulb for weeks. I'm sure it would really honk with 9 volts DC chop
input.

cheers
skipp

http://sonic.ucdavis.edu

: KD7TOG wrote:
: OK, here's a challenge to you guys ... I have been trying to ID a IC /
: inductor combination to generate 150 to 200 VDC ... in the nano-microamp
: range. I need to supply a bias voltage to an electrostatic microphone
: element.

: Any ideas ??

: Wish list:

: Very low current ... 2ma ;-)
: Runs from 5 to 9 volt DC source
: Minimal components

: Most of the specs I find for HV units ( backlight supplies ) are too much
: current. Most of the inductor type DC-DC converters seem geared towards low
: voltage high current apps.

: Will watch the discussion for tips and ideas ... all welcome.

: Thanks

: Tony, KD7TOG

: ( KD7TOG at earthlink dot net )

Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG

One more idea -- the old mass-produced geiger counters now available
cheaply on eBay have very simple HV supply circuits that use minimal
components, and run from 1.5 to 6 or so volts, depending on the model.
They come with a schematic and parts list. Although the parts are just
about all obsolete, you could find modern substitutes that would work.

Roy Lewallen, W7EL

KD7TOG wrote:
Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG

One more idea -- the old mass-produced geiger counters now available
cheaply on eBay have very simple HV supply circuits that use minimal
components, and run from 1.5 to 6 or so volts, depending on the model.
They come with a schematic and parts list. Although the parts are just
about all obsolete, you could find modern substitutes that would work.

Roy Lewallen, W7EL

KD7TOG wrote:
Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG

In article et, "KD7TOG"
writes:

Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG

This isn't a direct solution but it looked interesting if someone wants
to try it - Harry Lythall's accidental discovery of an LM317 series
voltage regulator as an RF oscillator at low HF.

http://w1.859.telia.com/~u85920178/tx/317-tx.htm

Use a toroidal core and/or a multiplying rectifier and the voltage could
be sizeable.

Len Anderson
retired (from regular hours) electronic engineer person

In article et, "KD7TOG"
writes:

Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG

This isn't a direct solution but it looked interesting if someone wants
to try it - Harry Lythall's accidental discovery of an LM317 series
voltage regulator as an RF oscillator at low HF.

http://w1.859.telia.com/~u85920178/tx/317-tx.htm

Use a toroidal core and/or a multiplying rectifier and the voltage could
be sizeable.

Len Anderson
retired (from regular hours) electronic engineer person

Thanks all for the ideas ... I have a couple of potential solutions.

Tony, KD7TOG