HV out of range when cold? ** Videos Included **

[bluevolume]

Here's a new scenario that's happening with my monitor.  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 30 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 45 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 can post a video of all this if requested.

[bluevolume]

I made a video of what this monitor does when I first turn it on from cold.  This is about the worst it gets; the humidity has been high here lately.

The camera starts focused on the back of the monitor.  There weren't really any visible sparks this time, but you can definitely hear them.

I'm posting 2 copies, one that's more compressed for quicker download.  I zipped them for easier download; they are encoded in DivX.
Monitor Startup - 4mb
Monitor Startup - 2mb

[bluevolume]

55 views and not one reply, interesting.

For anyone who cares, I have solved the sparking problem on my monitor.  It simply needed to be cleaned.  It still has some display issues until it warms up, but the fireworks and ozone smell are gone.  There's the short story, the long one is below.

In order to solve this problem, I had to use some good old electronics 101 thinking.  I knew that I had sparks jumping outside the anode cap, which means it must have been finding a ground outside of the tube.  Searching Google groups, I read someone mentioning applying Corona Dope under the anode cap.  This was supposed to resist the electricity flow, and break that ground.  I went ahead and did this on my monitor, and while it did still spark, I noticed that the sparks were different.  Rather than forming an arc pattern right outside the cap, the sparks were jumping further out, and were less concentrated.  In the process of adding the corona dope I had affected the unwanted ground, and the electricity was forced to take a longer path.

So maybe this should have been obvious from the beginning, but it dawned on me that if the sparks were jumping maybe 2" from the anode there had to be something providing a ground right there on the tube.  The actual monitor frame is closer to the anode than the lag spring is, so this is the only thing that makes sense.  I took a paper towel and soaked it in isopropyl, and cleaned the whole area around the anode, all the way out to (not including) the black compound that is on the edges of the tube.  The paper towel was filthy, lots of dust and grime.  I used a clean towel and ran it over again, much cleaner this time.

I let the tube dry, turned it on, and said goodbye to the sparking problem.  I was so happy that this worked; it was a great way to start the weekend.  This story is probably a bit drawn out, but I wanted to include the details.  I am now ready to continue on my project, hopefully with a monitor that won't trouble me for a while.

[grantspain]

in my experience the only thing you need to clean a tube is a vacuum cleaner,glass cleaner and cloths
i only use glass cleaner as most times there is a protective paint around the anode cap to prevent the sparking to earth and you don't want to affect the integrity of the paint.
first i disconnect the anode cap then using a paint brush and the vacuum cleaner i clean as much of the tube as possible,once most of the dust has gone  i then spray glass cleaner onto a cloth and clean most of the tube around the anode,clean the anode cap inside and out including the ht lead.then blow out any dust from the anode,make sure everything is completely dry then reconnect the anode cap
i would NOT recommend using alcohol based cleaners as it will destroy the protective paint