Sony Trinitron colour distortion

[19Seventy7]

Hi Pietro

The exterior may not look damaged but the force of the slam could've knocked the aperture grille inside the CRT itself, which is irreparable if it was knocked out of place.

Try the suggested ideas and report back, there's always help available here.

Good luck

[simpsons]

Ahh. Although a little late in the day, at last we know what happened.

It makes quite a difference to the possible faults which caused the purity issues you now encounter, as I am sure you realise.

For my money, I would go through the beam landing set up as detailed in the service manual, leaving the rubber wedges in position. It isn't difficult in itself. I have had PIL tubes, when dropped, not respond correctly but at least you will know what you have to deal with

The issue might be getting a red and blue raster as required but, should you have a DVD writer or access to one, then simply burn the coloured rasters and a cross hatch or PM5544 test card from Google. Alternatively, should your DVD player have a USB port input, then its easy, use a flash memory stick to record them.

Good luck.

Chris

[ben]

Originally Posted by Pietro123

No, I bought it at a thrift store, though when I arrived home and opened the hatchback the TV tilted and slammed.

Why didn't you mention this at the beginning?

[hans]

How old is this set? Usually the force needed to misalign the mask is great enough to cause other damage to the set. Usually cracking the printboards and case. If it just tilted onto cardboard I can't see that that have shifted the mask. I've fixed Sonys (90's and newer) with severe fall damage and the tube still ok. The worst case had the LOPT torn from the print and a cracke case, still the tube was ok.

Check the degausing and if the yoke is ok and in the right position.

[Pietro123]

Ok, I just took the TV apart and the yoke isn't touching the rubber wedges. I'll push it up and see if it gets better.

[Heatercathodeshort]

I had a number of Sony receivers booked in for repair with the complaint that the colour display was just a 'rainbow'. In every case the receiver had suffered a fall and dislodged the mask/grill and were written off.
I have never seen one with what appears to be moderate purity errors other than the degauss problem mentioned earlier.
In my experience Sony tubes require a heavy degauss current to clear purity errors and have often required a manual degauss [with a heavy current] to clear the stray magnetism when the posistor goes S/C and puts a very current through the coils for just a split second. Did some Sony's have two degauss posistors? Just my experience. John.

[space_charged]

It looks like the sort of purity errors you get with the yoke displaced. If he's lucky then it may be the yoke moved back when it was knocked.

[Maarten]

I've never seen Sony sets using 2 posistors (on 230V models anyway), but they did use low resistance types.

[Pietro123]

I tried moving the yoke but it didn't go up. Though when I tried the TV there was no more colour distortion on the left side and there's less on the right side. Convergence looks slightly worse to me but I could be wrong, might work on it again and see if I can fix it. Thank you all for helping!

[Refugee]

That will be fixable.
Have you loosened the yoke clamp?
The wedges may have shrunk but replacements can be found in old CRT computer screens.

[Maarten]

Sometimes even when you loosen the clamp, the yoke will need unsticking from the tape.

[Refugee]

If the yoke is well stuck it may only need the wedges sorted out.