I have a pretty bad monitor problem that so far I can't find a
solution for. Here's the details:

Wells Gardner k7000, 25" (Mounted in an arcade cabinet, connected to a
WinXP PC)
New cap kit, replaced flyback
Applied corona dope around anode connection (directly on glass)

When started up from cold, the flyback squeals and there's a "fizzing"
or "crackling" sound coming from the back of the tube. After about 15
seconds, the monitor display looks skewed and is rolling very bad,
sort of like trying to run it at an unsupported resolution. The
display doesn't cover the whole screen; there's probably 10% on the
bottom that is black.

After about 60 seconds the flyback has quieted down and "fizzing" is
less noticeable. Though the smell of ozone is very aparent now. The
display slowly moves out till it is filling the monitor, and the
picture stops rolling yet is still totally skewed and garbled.

After about 100 seconds the display jumps to perfectly correct, maybe
with the whites being a bit dull and yellowish. The fizzing is still
happening, though you really have to listen for it. From this point
on, the monitor looks great and works more or less correctly.

Its obvious that something is "warming up" during all of this, and
behaving better once it gets there, but I have no idea what it is.
I'm thinking that maybe the secondary HV is way too high, but I have
no way of testing this. The chasis has a new flyback and cap kit,
though I know there are more caps on there that weren't in the kit
(notably one that is as big around as a quarter). Can anyone diagnose
this from my description?

I have placed a video of this up on my website in DivX format. Here's
two links, one further compressed for quick download:
http://www.ferrellsny.com/media/sparky2.zip
http://www.ferrellsny.com/media/sparky2sm.zip

If anyone can help with this I would really appreciate it. I am
afraid to bring this cabinet into my house in this condition.

wrote in message
ups.com...
I have a pretty bad monitor problem that so far I can't find a
solution for. Here's the details:

Wells Gardner k7000, 25" (Mounted in an arcade cabinet, connected to a
WinXP PC)
New cap kit, replaced flyback
Applied corona dope around anode connection (directly on glass)

When started up from cold, the flyback squeals and there's a "fizzing"
or "crackling" sound coming from the back of the tube. After about 15
seconds, the monitor display looks skewed and is rolling very bad,
sort of like trying to run it at an unsupported resolution. The
display doesn't cover the whole screen; there's probably 10% on the
bottom that is black.

After about 60 seconds the flyback has quieted down and "fizzing" is
less noticeable. Though the smell of ozone is very aparent now. The
display slowly moves out till it is filling the monitor, and the
picture stops rolling yet is still totally skewed and garbled.

After about 100 seconds the display jumps to perfectly correct, maybe
with the whites being a bit dull and yellowish. The fizzing is still
happening, though you really have to listen for it. From this point
on, the monitor looks great and works more or less correctly.

Its obvious that something is "warming up" during all of this, and
behaving better once it gets there, but I have no idea what it is.
I'm thinking that maybe the secondary HV is way too high, but I have
no way of testing this. The chasis has a new flyback and cap kit,
though I know there are more caps on there that weren't in the kit
(notably one that is as big around as a quarter). Can anyone diagnose
this from my description?

I have placed a video of this up on my website in DivX format. Here's
two links, one further compressed for quick download:
http://www.ferrellsny.com/media/sparky2.zip
http://www.ferrellsny.com/media/sparky2sm.zip

If anyone can help with this I would really appreciate it. I am
afraid to bring this cabinet into my house in this condition.



My first guess is a bad flyback transformer. I would also look into
electrolytic capacitors since they tend to get better as they warm up. A can
of freeze spray is a great troubleshooting aid for problems like this.

My first guess is a bad flyback transformer. I would also look into
electrolytic capacitors since they tend to get better as they warm up. A can
of freeze spray is a great troubleshooting aid for problems like this.- Hide quoted text -

- Show quoted text -

The flyback transformer is new, replaced it along with the cap kit.

Do I just hit some of the caps with the freeze spray and watch for a
reaction?

wrote in message
ps.com...

My first guess is a bad flyback transformer. I would also look into
electrolytic capacitors since they tend to get better as they warm up. A
can
of freeze spray is a great troubleshooting aid for problems like this.-
Hide quoted text -

- Show quoted text -

The flyback transformer is new, replaced it along with the cap kit.

Do I just hit some of the caps with the freeze spray and watch for a
reaction?


Let it warm up until the problem goes away, then just start hitting various
areas of the board with a quick shot of freeze spray and see if you can get
the problem to reappear. If you did a cap kit that should have covered it,
it could be a cracked solder joint though, thermal cycles do affect those.

On Sep 28, 4:17 pm, "James Sweet" wrote:
wrote in message

ps.com...



My first guess is a bad flyback transformer. I would also look into
electrolytic capacitors since they tend to get better as they warm up. A
can
of freeze spray is a great troubleshooting aid for problems like this.-
Hide quoted text -

- Show quoted text -

The flyback transformer is new, replaced it along with the cap kit.

Do I just hit some of the caps with the freeze spray and watch for a
reaction?

Let it warm up until the problem goes away, then just start hitting various
areas of the board with a quick shot of freeze spray and see if you can get
the problem to reappear. If you did a cap kit that should have covered it,
it could be a cracked solder joint though, thermal cycles do affect those.

I would turn out the lights and see where the arcing is coming from.
Some times a little well placed RTV does wonders. Make sure you let it
fully cure though before turning the set back on again. Lenny Stein,
Barlen Electronics.

I went back at it today with a fresh perspective, and looked closely
for where the arcing was happening. It was right around the anode
cap, and some of the sparks were jumping a good 2" past the outer edge
of the cap. I ran my finger across the glass (after turning it off,
of course) and there was a little bit if grime on there. I soaked a
paper towel with isopropyl and wiped the entire back of the tube
clean, stopping just shy of the black spray coating at the sides. The
towel was filthy; a lot of stuff came off the back of that tube.

I let it dry and fired it back up. It sparked just a little bit, and
only for a few seconds, then stopped completely. I turned it on and
off a couple times and it is more or less gone. Too soon to tell if
this is a permanent solution, but I'm keeping my fingers crossed.

I let it dry and fired it back up. It sparked just a little bit, and
only for a few seconds, then stopped completely. I turned it on and
off a couple times and it is more or less gone. Too soon to tell if
this is a permanent solution, but I'm keeping my fingers crossed.

By "gone", I mean the problem is gone. The monitor is working
correctly now. I read that post again and realized it might be
unclear.

Thanks.