G07 monitor issue - Circular color glob in center of screen

G

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Hi all,
I have this G07 that's fully capped and I put in a new flyback as well.
The colors are accumulated to a dot in the center of the screen. Not
sure why this is happening. I measured the voltage across the HOT and I
get 130vdc. I can't turn it up or down. Could the HOT be bad? I thought
if you're getting voltage, then th HOT is good right? Anyone ever run
into this issue? It's not the tube as I put another chassis in and the
tube works fine. Any ideas?

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

Did you forget to plug in the yoke perhaps?
 
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Nope... Yoke is plugged in too. I'm stumped.
Anyone know if the hot would be the problem or not?
John
 
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well a dot in the center of the screen means that there is no magnetic
field moving the guns.

did it work fine before the cap kit? if so i would check all your
solder joints, even the flyback joints.

it could be the IC. but highly unlikely but there is a cap that goes by
the ic and check the solder so that it doesnt touch the ic.

With a dot in the center of the screen you have HV.
 
G

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docfran...@hotmail.com wrote:
> well a dot in the center of the screen means that there is no
magnetic
> field moving the guns.
>
> did it work fine before the cap kit? if so i would check all your
> solder joints, even the flyback joints.
>
> it could be the IC. but highly unlikely but there is a cap that goes
by
> the ic and check the solder so that it doesnt touch the ic.
>
> With a dot in the center of the screen you have HV.

It's actually really strange. Cap kit is fine. What could cause a
concentration to the center of the screen? Any other ideas??? I know
that I don't get the chatter when the monitor starts up. I'm suspecting
the HOT. What do you think?

John
 
G

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

Hi,
Do you own a High Voltage Probe? Also did the monitor work before
you capped it? Check your solder joints. If you do not own a High
Voltage probe use the back of your hand when the monitor comes up. Also
make sure you reconnected the black wire that goes around the tube.
Color on the screen indicates you have HV...maybe not enough. Also
check and make sure you installed the H and V deflection connectors in
the proper place if the connector was cut. Some monitors do not give
off a large krackle sound when the HV comes up. Also check that you
snapped in the Anode tube into the monitor securely. Make shure you
redischarge it before you remove it. Also check the H centering jumper
that it was not pulled inadventently.
I would lean towards your deflection circuit.

J & R

Baraka wrote:
> docfran...@hotmail.com wrote:
> > well a dot in the center of the screen means that there is no
> magnetic
> > field moving the guns.
> >
> > did it work fine before the cap kit? if so i would check all your
> > solder joints, even the flyback joints.
> >
> > it could be the IC. but highly unlikely but there is a cap that
goes
> by
> > the ic and check the solder so that it doesnt touch the ic.
> >
> > With a dot in the center of the screen you have HV.
>
> It's actually really strange. Cap kit is fine. What could cause a
> concentration to the center of the screen? Any other ideas??? I know
> that I don't get the chatter when the monitor starts up. I'm
suspecting
> the HOT. What do you think?
>
> John
 
G

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

I have a funny feeling it will be the IC on the chassis. I'll swap it
out tonight and will post my results. Thanks all for the input..
John
 
G

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

Color blobs mean the guns are firing but no sweep. Flyback and HOT solved
the last one IIRC. Did them both but could be just the HOT. The guns are
only 50V and 6.3V, not what I would call high voltage.

"J & R" <arcadeadventures@aol.com> wrote in message
news:1113184368.600913.138330@z14g2000cwz.googlegroups.com...
> Hi,
> Do you own a High Voltage Probe? Also did the monitor work before
> you capped it? Check your solder joints. If you do not own a High
> Voltage probe use the back of your hand when the monitor comes up. Also
> make sure you reconnected the black wire that goes around the tube.
> Color on the screen indicates you have HV...maybe not enough. Also
> check and make sure you installed the H and V deflection connectors in
> the proper place if the connector was cut. Some monitors do not give
> off a large krackle sound when the HV comes up. Also check that you
> snapped in the Anode tube into the monitor securely. Make shure you
> redischarge it before you remove it. Also check the H centering jumper
> that it was not pulled inadventently.
> I would lean towards your deflection circuit.
>
> J & R
>
> Baraka wrote:
>> docfran...@hotmail.com wrote:
>> > well a dot in the center of the screen means that there is no
>> magnetic
>> > field moving the guns.
>> >
>> > did it work fine before the cap kit? if so i would check all your
>> > solder joints, even the flyback joints.
>> >
>> > it could be the IC. but highly unlikely but there is a cap that
> goes
>> by
>> > the ic and check the solder so that it doesnt touch the ic.
>> >
>> > With a dot in the center of the screen you have HV.
>>
>> It's actually really strange. Cap kit is fine. What could cause a
>> concentration to the center of the screen? Any other ideas??? I know
>> that I don't get the chatter when the monitor starts up. I'm
> suspecting
>> the HOT. What do you think?
>>
>> John
>
 
G

Guest

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

yes the guns may only require 50 or 6.3v but you still need the high
voltage 20,000 volts to get a picture.

the 20,000 vdc are positive and the guns shoot out electrons and
require the high positive to draw out the electrons or there will be
electrons floting all over inside of the tube which would cause the
colors to go anywhre on the screen.

so it is not the flyback (have hv due to something on picture) or the
Hot cause you tested it already (130vdc), yoke and tube is fine (cause
you tested it on another chassis).

i would still check all your solder joints and the IC 501

im positive it is one of these.

but again i ask was the monitor known to be good before the cap kit.
 
G

Guest

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

docfran...@hotmail.com wrote:
> yes the guns may only require 50 or 6.3v but you still need the high
> voltage 20,000 volts to get a picture.
>
> the 20,000 vdc are positive and the guns shoot out electrons and
> require the high positive to draw out the electrons or there will be
> electrons floting all over inside of the tube which would cause the
> colors to go anywhre on the screen.
>
> so it is not the flyback (have hv due to something on picture) or the
> Hot cause you tested it already (130vdc), yoke and tube is fine
(cause
> you tested it on another chassis).
>
> i would still check all your solder joints and the IC 501
>
> im positive it is one of these.
>
> but again i ask was the monitor known to be good before the cap kit.

Hi all.....

O.K..... It was a case of the solder joints not connecting. There is a
5 pin male header on the chassis Q1 thru Q5. The female yoke connector
plugs in here. There were 2 traces (Q1 and Q2) which were not making
continuity. I used a strand of braided desoldering wire to create the
trace, flowed solder over it and voila! Monitor fired up and the
chatter came back! Write this one down for the books. I couldn't even
see the traces cut until I looked really close and did a continuity
check!


John
 

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