Palsonic TV doesn't degauss - posister stuffed?

I picked up this Palsonic TV which seems to work fine except for badly needing a degauss - blue in the middle to red in the corners. Thought if I fix it it'll go in my parent's holiday house...

It doesn't do the degaussing buzz on first turn-on, so I'm assuming that the MX73 18 ohm posistor is rooted. I know what's supposed to be inside these, but I don't know what the cold terminal resistances should be - anyone? Guessing I'll find 18 ohms somewhere ;-) In-circuit, I see 40 ohms to one pin, just a couple of ohms between the other two.

How fussy is the TV likely to be - can I fit "almost any" posistor and expect it to work? Where's the best place to get one?

Clifford Heath.

Reply to
Clifford Heath
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if everything else is ok, it would have to be this. I havent had any problems using ones from other monitors of the same screen size, but really rare to have one fail.

I have seen 2 terminal devices (that look like big, thick disc ceramics) used in place of these in more modern CRT monitors.

I assumed that they are one of those gadgets (I cant remember the name

- posiswitch maybe?) that were used in series with speaker leads and would quickly go to a high resistance when a certain current was reached, then reset when it was removed - for protection purposes.

WES components may have them.

Reply to
KR

Download

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from WES Components and see if it looks like any of the degaussing thermistors on page 3-3.

If it does, probably the one in the catalog will work OK.

Reply to
Bob Parker

I had a "SONWA" 51" TV that had red portions in exactly the same spots on the screen, very obvious when screen was all blue on an empty station.

What I worked out is that you can place small magnets around the tube at strategic spots that will remove the red spot (ie turn blue, as seen on an empty station).

I managed to hot glue a bunch of small magnets above the tube , and the colour tint has returned to what it should be.

How is that for a non- electronic fix?

Reply to
Nomen Nescio

"Everyone" knows the best way to adjust gun alignment is to remove the deflection coils from the tube neck and rap it smartly with a 1Kg rubber mallet!.

Reply to
Mark Harriss

HEHEH :)

Some 30 years back my former boss (and self proclaimed "expert") tried tapping the neck of a 26" black and white tube with a large screwdriver to (hopefully) dislodge some screen phosphor material had come loose and fallen into the guns, causing gun shorts, and a lousy picture (can't remember the exact symptoms.)

This had happened after the set had somehow been laid on its back or tipped backwards, and the customer wanted a "cheap" repair.

AS well as attempting to show us all how clever he was by doing this - he seemed to find it exciting watching the "sparkles" as the tapping dislodged some of the stuff, and the problem looked like it was getting better but soon changed his tune when the glass neck suddenly cracked, fireworks erupting in the gun assembly as it let down to air, taking out the horizontal output transistor and (possibly- cant remember exactly) damaging the power supply in the chassis also, before anyone had time to unplug the set.

IIRC we had a spare tube from a junked set which wasn't too hard to install (and probably should have probably been done in the first place) , but there was a lot of time wasted in fixing the power supply / Horizontal transistor which was not an easy job in that set.

Reply to
KR

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