Re: GO-5 question

Hi Doug!

Answers scattered inside your message...

Doug Jefferys wrote:
>
> > > I'd love to find a schematic to my early series G07 monitor (801) ...
> Speaking of GO-5, I've got a cocktail Asteroids that's beginning
> to fade. Rather than those razor-sharp brilliant points of light
> we're used to seeing for Asteroids bullets, I'm getting relatively
> unfocused bullets, and it's also difficult to find a brightness and
> contrast setting that gives me good definition between the "bright"
> vectors and the "dim" vectors.
>
> A little inspection under the hood revealed that the previous owner
> has shorted (!) out one of the big ceramic resistors.
>
> 1) Exactly what the *hell* was the operator thinking? Removing the
> shorting wire results in a blank screen, so I'm assuming the resistor
> itself is toast.

This resistor is part of the deflection circuitry. In some monitors
(19") this was just a peice of wire, in the 13" it was a resistor. If it
works, that is if the picture is not too large/small, then I would leave
it shorted.

>
> 2) Why does the monitor work with the jumper in place, and could it
> be responsible for the poor video performance I've got (either by
> itself or by slowly degrading other components)

See above, and no it won't cause the video problem.

>
> 3) Any other hints for restoring the beast?

The picture getting fuzzy implies fading caps. I would replace all the
capacitors in the HV cage. Try and get low ESR and 105 degree " caps.
These cost a little more, but are well worth it.

>
> Later,
> Doug.
..

John :-#)#

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