Tech: F1 fuse blown on WG K7000

Archived from groups: rec.games.video.arcade.collecting (More info?)

K7000 manual is on atarijeff.com

Archived from groups: rec.games.video.arcade.collecting (More info?)

I think check Q1, pretty sure that is a troubleshooting chart on the WG site

--
AF


"Mike Singer" <pinbuoy@comcast.net> wrote in message
news:Jp6dnZX3PKLnD07fRVn-ug@comcast.com...
> Hey all,
>
> Got this game with a dead monitor.
> Check it out and the monitor board was loose and it had blown a fuse.
> I remount it and replace the fuse.
> It's F1 - 1.5A SB.
> Blows on powerup.
>
> typically the fuse is for the flyback.
> If the board touched the chassis, is there something else that could be
> blowing the fuse?
> Does anyone have schematics for this model or is it buried on Bobs page
> somewhere?
>
> Thanks
>
> Mike
>
>
>

Archived from groups: rec.games.video.arcade.collecting (More info?)

"Mike Singer" <pinbuoy@comcast.net> wrote in message
news:Jp6dnZX3PKLnD07fRVn-ug@comcast.com...
> Hey all,
>
> Got this game with a dead monitor.
> Check it out and the monitor board was loose and it had blown a fuse.
> I remount it and replace the fuse.
> It's F1 - 1.5A SB.
> Blows on powerup.
>
> typically the fuse is for the flyback.
> If the board touched the chassis, is there something else that could be
> blowing the fuse?
> Does anyone have schematics for this model or is it buried on Bobs page
> somewhere?
>
> Thanks
>
> Mike
>
>
>

Check closest to the fuse, rectifier diodes D19 -22. If not that, check the
regulator, HOT, retrace cap. If you suspect the flyback, pull the HOT out of
circuit, if the fuse still blows it's probably the rectifier diodes. I've
seen those diodes go bad on their own, but more so from powering the monitor
without an isolation xfmr.

Archived from groups: rec.games.video.arcade.collecting (More info?)

Take a look at your Horizontal output transistor. The critical safety
cap will blow the fuse along with the 2 other Micas that are near by
that are the same shape but a little smaller. The diode you are
measuring is fine. Take a look at the circuit. Also check the Voltage
regulator. I forget the rule of thumb on this one. if 1 to 4 shows a
short its bad.

RJ

Archived from groups: rec.games.video.arcade.collecting (More info?)

Well here it is a month later, finally looking at this thing.
The 4 rect diodes all measure the std junstions drop in circuit one way
and a reading that rises to approx 1.770 the other way

I'm guessing this is because of the cap.
Are these OK or do I need to take them out of circuit?

If so can I just take the cap out of circuit instead of all the diodes?

d23 measures correctly
d24 measures the junstion drop in both directions
I'm guessing this one is bad, unless it's a "in circuit" thing.

Thanks

Mike

> > Got this game with a dead monitor.
> > Check it out and the monitor board was loose and it had blown a fuse.
> > I remount it and replace the fuse.
> > It's F1 - 1.5A SB.
> > Blows on powerup.
> >
> > typically the fuse is for the flyback.
> > If the board touched the chassis, is there something else that could be
> > blowing the fuse?
> > Does anyone have schematics for this model or is it buried on Bobs page
> > somewhere?
>>
> Check closest to the fuse, rectifier diodes D19 -22. If not that, check
the
> regulator, HOT, retrace cap. If you suspect the flyback, pull the HOT out
of
> circuit, if the fuse still blows it's probably the rectifier diodes. I've
> seen those diodes go bad on their own, but more so from powering the
monitor
> without an isolation xfmr.
>
>