Nixies, was Re: Octal

[Roy J. Tellason]

On Sunday 03 September 2006 06:50 pm, Tony Duell wrote:
> > On Saturday 02 September 2006 06:25 pm, Tony Duell wrote:
> > > [...]
> > > Another way to do it is to use 'back to back' mains transformers.
> > > Connect the 'secondary' (which is now used as a primary) of a small
> > > mains transformer to the (AC) output of the trnasformer you're using to
> > > provide the logic supplies (or to the output of another mains
> > > transformer if you're using the SMPSU for the logic).  Then rectify or
> > > voltage double the output of this extra transformer (the winding that
> > > was originally the primary) to get about 200V DC.
> >
> > You don't need a voltage doubler to get most of the way there.  Peak
> > voltage of a lightly loaded rectifier-filter setup running off "110" (or
> > "115", "117",  whatever the case may be -- it seems to be trending higher
> > as time
>
> I would seriously recomend against rectifying the mains for something
> like this. Non-isolated PSUs have the nasty habit of making things live
> that you least expect, and may kill you (or worse, damage a classic
> computer).

Oh,  I wasn't suggesting that,  simply pointing out that once you got your 
isolation a simple rectifier would do the trick just fine...

I've had my experiences with non-isolated equipment,  more than I ever wanted,  
and don't plan to build any to add to that.  :-)

> If you use back-to-back transformers as I've suggsted, the actual voltage
> got get out depends on the turns rations, of course. Maybe a simple
> rectifier will be enough, maybe you need a doubler.

Many suggestions that I've seen illustrated like that suggest using two 
identical transformers,   which should get you the same thing out as you put 
in.

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