Re: Ampliphone HV board

Hi Jess!

I don't think this would help at all, the problem is not that the
regulator fails and then the HV croaks, more that the HV transformer
(Xformer) burns out due to poor design. I suspect the insulation on the
windings left a bit to be desired.

Interesting isn't it that on raster monitors, that Electrohome monitors
eat a LOT of flybacks yet the Wells Gardner raster monitors hardly EVER
lose one. Yet on the XY monitors, i found that LOTS os Wells Gardner
Xformers croak, but the Electrohome version seems quite reliable....

John

("life...don't talk to me about life" Marvin the Paranoid Android)

Jess Askey wrote:
>
> What is the the common way in which the HV transformers fail? Is there a
> certain winding that gets shorted turns from the heat?
> I think that this has been talked out before, but would replacing the
> small T0-220 cased +/- 24V regulators with larger T-03 versions ( and
> eliminating the big hot resistors) help to preserve the HV transformers?
>
> MKDUD@aol.com wrote:
> >
> > In a message dated 6/5/99 6:19:25 PM Eastern Daylight Time, davids@oz.net
> > writes:
> >
> > << Any one have a working spare they want to let go of? The quantum I just
> > won
> > on e-bay is missing that board (and the game board but I have that).
> >
> > I have like 6 dead HV boards. I keep hopeing Zanen will come up with an
> > inexpensive replacement for that transformer.
> > >>
> >
> > Have you tried ringing the transformer to see if that is the problem - I
> > use a Bob Parker / Dick Smith LOPT tester. I might be able to repair a board
> > for you if your HVT's are not dead. I'm writing an Amplifone HV faq (yes, it
> > will be done soon!) that will really help anybody trying to repair these
> > boards....
> >
> > Michael Kelley

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