basic TV question

My tv, and my 7 crt's give a nice "boing" when swithed on, so there must be something wrong with your tv. There sould be a coil around the front of the tube, and a relay and ptc resistor to let the current trough that coil fade away to zero. That somewhat de-gauses your screen. But only if it works. Very big errors need an external paddle de-gauser.

"default"

It's essential.

Your problem is that the PTC thermistor circuit that drives the coil has failed.

May be because of the PTC device itself, a blown fuse or a bad connection to the coil.

.... Phil

Do you have a soldering gun? They are good degaussers.

John

Thanks

I do, and tried that. Winding a coil and connecting it in place of the tip may be a winner. The gun alone, with a regular soldering tip, tried in all orientations, did help - the side bands are almost gone and the center (where I didn't think there was a problem) looks better.

But there are still two pesky areas on the bottom corners. If I didn't know better, I'd be looking for a hidden magnet.

Just fix the TV.

I never thought of that, I was cobbing something together the other day to demagnetize some tweezers.

George H.

Do you have kids? "Hidden magnet" just made me think of that for some reason.

Just fix the dang thing.

Hmm, could they be due to the speakers in the set itself, or a nearby stereo?

Best regards,

Bob Masta DAQARTA v5.10 Data AcQuisition And Real-Time Analysis

Now where's the fun in that? It is a big beast and I don't want to move it.

Calculating the inductance for a degausser is more rewarding than poking about in TVs.

No kids or magnets that I see. Speakers inside the set have magnets no doubt.

Fixing is a less desirable option. Ages ago I repaired TVs for a living. Good chance that if it needs any part it will have to be ordered, since there are no parts outlets around here. It is a large beast. Could just be a fuse . . .

he

nt?

p,

We had a cheapy Daewoo set for the kids where the degausser failed. It has a relay on the main board that flexes the contacts slightly when it actuates. The solder joint eventually failed and all it took to restore it was to clean off the remaining solder and re-solder it. Works fine again.

G=B2

default schrieb:

unlikely, PTC is more likely.

Some time ago, I had a similar problem: Built in degaussing didn´t work and the PTC sat inaccessible below the very large CRT (>30"). I took the degaussing coil and circuitry (which was fortunately on a seperate print) from an old set set, which was scrapped at this time. I held the coil in front of the TV and moved it away slowly, the way it was done before built-in degaussing was standard (prior to ~1960) (I know this from american literature only, the first color-TVs in central europe allready hat built-in degaussing (~1967)

greetings, Rudolf