On Wed, 23 Nov 2005, Bob Blick wrote:

> Hi Brooke,
>
> You might try a variation on this:
>
> http://bobblick.com/3cell/
>
> I forget exactly what voltage it starts with, but you should be able to
> play with resistors here or there and get it to start.
>
> Moving Q2's emitter to the input voltage is probably required too.

Would a JFET based hf oscillator work to produce an initial bias ? A 
JFET may have gain at zero Vg. There are also 'programmable base' 
mosfets afaik. Could one of these be used ? e.g.:

http://www.aldinc.com/ald_epadfaq.htm

can produce parts programmed for Vg=0.2V.

Last, a vibrator <g> circuit could be used to convert the bootstrap 
voltage, using a depletion mode mosfet to turn it off once the main 
voltage is present.

Peter
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