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1988 Sony kv-p14d trinitron CRT repair

I'll see what I can come up with in terms of external degaussing. Welding magnet in a drill sounds like an easy starting point before buying the green wand. I don't have an old tv laying around to scavenge the coil.

This unit does not have a tilt setting/coil to correct tilt and it is significant in my cade, which is why I suspect the yoke has shifted.
 
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I'll see what I can come up with in terms of external degaussing. Welding magnet in a drill sounds like an easy starting point before buying the green wand. I don't have an old tv laying around to scavenge the coil.

This unit does not have a tilt setting/coil to correct tilt and it is significant in my cade, which is why I suspect the yoke has shifted.
With that much raster tilt, it does seem suspicious that the yoke has rotated. This practically never happens on its own, even after loosening the clamp the yoke can often be difficult to get moving as the plastic tongues under the clamp normally bite into the fiberglass tape on the neck, It is suspicious then that somebody moved it, or was working on that. You could also check if the white paint, normally on the adjustment rings has been cracked or broken.
 
Also the fact that it seemingly has perfect geometry apart from the tilt and shift (the osd volume bar is hardly in view) makes me assume the yoke is not in the correct place rather than (only) a degaussing issue.

But you and I will have to wait until I get it out of storage to know more...
 
I got the monitor out of storage. By the sound of it, the internal degauss appears to work just fine. It zaps on cold start and not on warm start.

My plan of action is to gently try an external degauss using a corded drill's back end, and after that -not expecting much from the degauss...- open it up and see if the yoke position is telling me anything.

I assume a corded drill's back end isn't magnetically strong enough to actually damage the trinitron grille?
 
I have opened the monitor to check the yoke position. I'm still alive.

I saw there are two rubber wedges between the yoke and the tube, one at 12 o'clock and one at 3. I don't know if it's normal that there are only two? I saw no others living somewhere else inside the TV.

Anyway, the yoke sits flush against the wedge at 3, but far away from the one at 12. So it seems to me that the yoke is definately shifted and possibly missing wedges.

The adjustment rings are still held by the original glue; I will not touch these.
 

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I don't think the wedges are magnetic.

In any case, I managed to wiggle the yoke loose. Using AMiga Deluxe Paint for test screens, I managed to get the yoke to display a correct picture both in terms of colour and tilt. Fixed the yoke with the screw. Reassembled and connected everything and...bad corner. I had fixed the yoke facing east and use the TV facing north. So now I've done it again facing north. I've also corrected the horizontal alignment. I still need to put new adhesive on the wedges and apply it, then put the TV back together, and hope everything is still OK after all that.

Here's the evidence attached. And I'm still alive! Even after my forehead touched the -luckily still OK- anode cable when I dove in too deep.

I'm not claiming it's all 100% but to my eyes it is, and the quality of this monitor really shows. In real life, not on photo. People rave about the Philips Personal Monitors, but these Trinitrons have better resolution, less apparent flicker, and a better image. And they fit in the same convenient space (both 14" monitors with small housing) and are period correct. I can also confirm that, even though they are PAL spec, they sync up to 50Hz just as well as 60Hz.

They are really sensitive for stray sync signals, so if you use a SCART switch, make sure all sources are off except for the one you use. And apparently the monitor only auto switches to SCART on the Amiga's higher resolution, not on the lower res of the Sega's and C128. But that's just one button press to get going.
 

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Glad to be of help. I've owned quite a few Trinitron displays and TVs over the years. About the only gripe I ever had was the slightly visible shadow of the mask support wire.
Do keep an eye on the PSU voltages--Sony was notorious for a time for lousy power supplies.
 
I've already closed the tv again, so I'll have to believe the psu is ok... But I think the lousy series were more recent. I did do a visual of the elcos and none looked bad, so there's that.
 
By the way, my only previous experience with Trinitron is CRT computer monitors. I assume 17" 1024x768 things. On those you could hardly see the vertical wires, but there was a rather obvious horizontal wire about 2/3rds down. I also found that quite annoying.

This little 14" PAL monitor however does not have a horizontal line any more obvious than the rest of raster (which is more pronounced than on those high res computer monitors), so there's no annoyance there, aspecially when coming from a shadow mask monitor. It looks like a regular shadow mask CRT, only a bit better.

My kids also find that this monitor has a lot less flicker than the Philips I used before. Also you can't put the contrast and brightness on headache inducing levels on this Sony like you could on the Philips, but that's a plus rather than a minus. Three sources of headache less = better gaming.
 
The only thing better than this monitor is the timing: normally I'll receive a Playstation 2 (it's not just a console, it's a supercomputer, so fitting for this forum) tomorrow, for which I needed the upgrade from 320 res monitors to PAL.
 
If you apply "glue" to the wedges it must be inert. Don't use latex based contact adhesive or acid cure silicone rubber. Use non-acid cure silicone rubber.
 
The Playstation 2 and its 55 games have arrived. PS2 outputs 480i for most games. This works just perfect on this PAL monitor. So now I have a nice 14" monitor that does everything from ye olde 320 res computers up to the last generation consoles that you'd still want to play on CRT.

The only potential improvement would be the sound, which sounds good but is mono on this TV.
 
One more thing...every now and then from a cold start, the monitor will initially be very blue with yellow instead of white. Waiting a good while or, of course, slamming the left side, will get it OK. I'm quite sure this is one of the three Trinitron beams not working and it seems like a bad contact/solder joint to me.

Can anyone confirm or correct my reasoning, and perhaps offer some guidance as to where I should try to find the supposedly bad connection? On the tube part, on the chassis part, which of the three beams as far as identifiable...
 
This TV is making my life a bit harder than it should be. I have not yet tackled the above issue, and here is the next one:

I was trying to hook up a Tandy Color TV Scoreboard (Pong console, the most advanced version with color image, 88 games and a lifesize rifle for a lightgun!). I know that the Tandy works, tested on another TV. On this Sony however, the TV can't lock to the channel. If I stop the auto scan at the right moment I get a distorted version of the image, but firmly locking or a good quality picture is a no-no. The auto-scanning procedure itself works perfectly.

Sooo...would the TV tuner module be faulty? Or perhaps the AGC circuit, as it does appear to find the channel but not as a strong signal? I read about testing the AGC by supplying my own voltage to the AGC pin. A bit beyond my current level...
 
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And I'm still alive! Even after my forehead touched the -luckily still OK- anode cable when I dove in too deep.
Congratulations (albeit belated) on that. For six months (more than half a lifetime ago), I worked a temporary assignment in Los Angeles Unified School District computer repair shop. Worst I got was touching 120VAC while working on a PET, but we had one OMR apprentice, who was working on a monitor, and she brushed up against 12kV. She shook it off, but the expression on her face was priceless.

As to hooking up the Tandy video game, yeah, sounds like tuner trouble of some sort.
 
I've opened the TV.

-bad connections in the SCART: I see that multiple of its legs are loose in the PCB; I'll solder them all.

-loss of blue upon startup, returns after a few minutes or with a Mighty Whack: the neck board solder joints are in poor shape; I'll solder the entire board after discharging the tube.

-tuning to the console issue: I see that this TV has one of those metal cased tuner blocks, as well as a similar AGC block. After I've done the above two repairs, I might monitor the AGC voltage while trying to tune into the console to see if that tells me anything. I didn't see anything clearly bad on the main board housing the tuner and AGC. Some capacitors on the board might be out of spec, but at least they didn't look terrible.
 
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