Re: Cinematronics HV supply problem

If you've already swapped out the 723 regulator and the 47uF/100V
electrolytic without success try the two 22uF/50V axial lead
electrolytics and the TIP31A transistor. The other transistor in
the unit I'm looking at now is a BD537. I don't have another one
to check against to see if this one is the original or not. If you
replace all these and it still doesn't work you could pull and check
the two polyprop' caps C31 and C41, check the diodes and
try to ohm out the resistors. If the problem is in the transformer
windings, or on the secondary side, you might as well throw it
in the trash.

Good luck,
Dave

----- Original Message -----
From: "Matt Rossiter" <rossiter@ni.net>
To: <vectorlist@synthcom.com>
Sent: Tuesday, April 02, 2002 11:34 PM
Subject: Re: VECTOR: Cinematronics HV supply problem

> It's a Keltron HV unit. Instead of +90 and +400 I'm getting something
small
> like +3 and +22. I've swapped the IC, and one of the caps. I'll try
> replacing them all and see what happens. If that doesn't work, I can't
think
> of anything else.
>
> Any suggestions are welcome.
>
> Matt
>
> David.Fish@axcelis.com wrote:
>
> > Matt,
> >
> > Alot depends on the type of Hi-V circuit that your monitor
> > has. Is it the on-board type or one of the two off-board
> > types (Keltron or PTK). Also, what do you get for the other
> > two voltages; the +400V and the +90V? It might be easier to
> > narrow down with that information.
> >
> > As for recapping, there are two caps on the on-board style
> > that could conceivably cause a low output voltage: C19 and
> > C20, a 5uF @100V and a 10uF @100V electrolytic, respectively.
> > If I recall correctly there's not much that can be swapped
> > out in a Keltron and I think that the PTKs are sealed.
> >
> > Dave
> >
> > -----Original Message-----
> > From: Matt Rossiter [mailto:rossiter@ni.net]
> > Sent: Tuesday, April 02, 2002 2:58 AM
> > To: vectorlist@synthcom.com
> > Subject: VECTOR: Cinematronics HV supply problem
> >
> > I'm only getting about 1.4K out of a HV supply. I've verified that it's
> > definitely the HV unit. I haven't worked on one of these yet, but I'm
> > thinking maybe a simple cap kit? Or maybe swap the IC?
> >
> > Suggestions?
> >
> > Matt
> >
>
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Received on Wed Apr 3 04:09:19 2002