1. Home
  2. Electronics Repair
  3. High vottage too high? ;)

High vottage too high? ;)

I'm working on a Sony KV2080R 19" color, fairly old, but the question sort of relates to all tv's.

It worked well except I heard a few cracks and saw a blue light coming from the back of the tv. It was a spark about 1 1/2" long from the flyback transformer to another part of that, shaped soemthing like a BIC lighter with square corners. Is that the tripler?

As you can tell, I'm only an amateur, but I've had good results in the past 30 years with 3 or 4 tv's and one microwave oven by covering sparking areas with GE Silicone cement/sealant.

This time, I put on a quarter inch coat (I don't think it will dry right if it is too thick), and let it dry 12-20 hours and then the spark moved somewhere else on the transformer. That happened two more times, with the spark moving each time, and then a third time the spark was at the base of a capacitor mounted to the pcb but next to the flyback. Coated that with GE silicone and then the spark was back on the flyback, real short, only an eighth of an inch, and at the surface of an earlier heavy coat of my silicone (I put a first coat of

1/4 inch on, and since I'm still having trouble this time, I've been putting on a second quarter inch coat.)

Is this not uncommon? or Is the high voltage too high? or Do SONYs have higher voltage than the other tvs I've done this with? or Do you disapprove of the whole technique? :) or Why is this happening this time when it never did before?

I didnt' really wait to see how many times it would spark when this all started, because I thought it was bad for the tv to be sparking at all, ??, so I would turn it off, but some later times it was hard to find the spark, so I would leave the tv on, and I've noticed that lately it only sparks about 4 times, every 10 seconds, and then it seems to stop. This last time, it only sparks 3 times and then stops for at least 10 minutes (when I turned the tv off each time) and wouldn't start again if I only left the tv off for an hour or two. I think after 12 or 24 hours it will spark again, 3 times, and stop.

I'm keeping the tv for myself, so maybe I should just live with this??

From early on I noticed that either the spark doesn't affect the picture, or it makes one white horizontal line across the picture for a split second.

I have half a caulking tube of of GE sealant, and I can keep putting the stuff on until I've covered everything within 2 inches, but I thought I should ask you guys before I went much further.

If you are inclined to email me for some reason, remove NOPSAM :-)

Reply to
mm
Loading thread data ...

Replace the flyback, Probably has a crack

Reply to
Charlie East

that object could be a fusible resistor. In any case, if you mean to keep that tv, don't mess about wasting your time with this botch repair. Just buy a new transformer before you end up damaging the nearby circuitry- ICs dont tend to like being zapped by

20,000 volts ;-). check the reference in the
formatting link
website.

-B.

Reply to
b

Figure out exactly where the crack is that the spark is coming from and caulk over that. If all else fails, replace the flyback but usually you can fix arcing problems like that.

Reply to
James Sweet

Thanks. That's what I wanted to hear, if I was the only person doing things this way.

Believe me, I looked each time, where the spark was at first and each time it moved, and I couldn't see either a crack or a pinpoint hole or even a mark. That's why I started to think the high voltage was higher than normal.

(A couple of the places where sparks started or ended were at a boundary of some sort, like the bottom or where the metal core met the rubber cover. But in the other 4 cases, I could find no crack. The spark moved every time!)

To Charlie and B: Thanks for replying but it's really not worth buying a flyback. It's not high def, it's going to be obsolete in 2 years, and I have lots of tvs. This will just be a spare.

The goal of my question was to understand this, only secondarily to fix the tv.

If you are inclined to email me for some reason, remove NOPSAM :-)

Reply to
mm

Its necessary to remove every trace of carbon before applying insulator, otherwise it wont work. Practically, it will die quickly, bin it.

NT

Reply to
meow2222

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.