UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Reply
 
Thread Tools
Old 22nd Jun 2024, 5:31 pm   #1
chroma04
Pentode
 
chroma04's Avatar
 
Join Date: Jul 2008
Location: Doncaster, South Yorkshire, UK.
Posts: 119
Default Sony KV1800UB C.R.T. Spots

Hi,

Firstly, I believe this issue has been mentioned on this forum before, so mods please accept my apologies if this is the case. I have a question concerning my Sony KV1800UB television set.

Basically, over the last year or so, the set has developed 'spots' in the corners and top edge of the C.R.T. This is a physical issue rather than electronic, as the spots/marks are present with the power off. I seem to recall that I have read about this issue before (perhaps on this forum) that the C.R.T. has a glass frontage that is bonded to the actual C.R.T. so could the issue be due to the adhesive failing at these points?

I should perhaps mention that this issue seems to have occurred during a recent house move, where the set was in storage for a couple of days, so could this be the root cause of the issue, due to changes in temperature/humidity, for example?

The set is now installed in a warm room and doesn't appear to be getting any worse, however I'm just curious to hear of any forum members' thoughts. Also, are the 'spots' likely to spread over the whole area of the C.R.T. face, in time?

Thank-you in advance,

Adrian.
Attached Thumbnails
Click image for larger version

Name:	DSC03499.jpg
Views:	212
Size:	44.6 KB
ID:	299427   Click image for larger version

Name:	DSC03500.jpg
Views:	216
Size:	134.7 KB
ID:	299428   Click image for larger version

Name:	DSC03501.jpg
Views:	191
Size:	55.8 KB
ID:	299429  
__________________
Chroma 04
chroma04 is offline   Reply With Quote
Old 22nd Jun 2024, 6:02 pm   #2
Paul_RK
Dekatron
 
Paul_RK's Avatar
 
Join Date: Nov 2003
Location: Fakenham, Norfolk, UK.
Posts: 4,356
Default Re: Sony KV1800UB C.R.T. Spots

My KV1800UB has quite a nasty case of these too. I think moisture must have been responsible, I noticed the spotting after it had spent some years on the floor in an unheated and somewhat damp front room. That was in our former house, which we left five years ago: it's now in an unheated bedroom, but with no particular damp problem and dehumidifiers at work in winter, and I don't think the spots are spreading.

Paul
Attached Thumbnails
Click image for larger version

Name:	kv1800.jpg
Views:	142
Size:	71.6 KB
ID:	299434  
Paul_RK is online now   Reply With Quote
Old 22nd Jun 2024, 6:11 pm   #3
jhalphen
Hexode
 
Join Date: Jul 2004
Location: Paris, France
Posts: 358
Default Re: Sony KV1800UB C.R.T. Spots

Hi to all,
Hi Chroma04,

See a photo i gleaned from a forum (maybe here), also a Sony 19" Trinitron.
Much worse case than yours.

It is indeed dampness/mould ingress between the plastic laminated annti-implosion protection and the actual CRT glass faceplate.

No solution was offered other than dissolving the glue (which type?) to separate both.

In the USA this is a well-known problem with 1960s round colour CRT, and it's called "cataract".
Numerous YouTube videos on the topic.

Their solutions, depending on CRT maker & glue type :
- hot air gun (danger!) + steel wire pulled across for separation.
- soaking CRT in water for days, then picking with a wooden dowel.

In both cases, it's messy, requires patience and suggested as an outdoor job.
...and you have to entirely remove the CRT from the receiver.

Sorry! for no quick & easy fix.

Best Regards
jhalphen
Paris/France
Attached Thumbnails
Click image for larger version

Name:	CRT Defects-01 - Trinitron Faceplate Spots.jpg
Views:	158
Size:	118.1 KB
ID:	299437  
jhalphen is offline   Reply With Quote
Old 22nd Jun 2024, 11:15 pm   #4
simpsons
Octode
 
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,553
Default Re: Sony KV1800UB C.R.T. Spots

Jerome is spot on. No pun intended!!

I had the same problem, and removing the gel using a flexible bade was quite difficult.

Another idea is to inject butylacetate into the gel which will dissolve the gel slowly, adding additional injections as required.

Chris
simpsons is offline   Reply With Quote
Old 23rd Jun 2024, 12:44 pm   #5
chroma04
Pentode
 
chroma04's Avatar
 
Join Date: Jul 2008
Location: Doncaster, South Yorkshire, UK.
Posts: 119
Default Re: Sony KV1800UB C.R.T. Spots

Thank-you to everybody for the replies.

The issue does appear to be as I suspected, possibly instigated due to the move and subsequent storage.

Paul, it is encouraging to hear that the issue does not appear to be worsening with your set. I'm hopeful that, given its current location, mine will not progress.

As has been suggested, the remedy of removing the laminated anti-implosion protection (by whatever means) sounds like a big job and would in any case be well beyond my abilities. As such, I think the set is best left alone. At least I now know what the issue is!

Best Regards,

Adrian.
__________________
Chroma 04
chroma04 is offline   Reply With Quote
Old 23rd Jun 2024, 1:19 pm   #6
toshiba tony
Heptode
 
toshiba tony's Avatar
 
Join Date: May 2006
Location: Accrington, Lancashire, UK.
Posts: 987
Default Re: Sony KV1800UB C.R.T. Spots

What an interesting problem, I spent a lot of years at Sony but never saw this problem. I have dementia now but even the 1810's didn't scare me. So what happens to the tubes on these? We used to get low emission and I seem to remember they were low focus potential sets but this is a new one on me.
toshiba tony is offline   Reply With Quote
Old 23rd Jun 2024, 1:30 pm   #7
greg_simons
Octode
 
greg_simons's Avatar
 
Join Date: Jul 2004
Location: Evesham, Worcestershire, UK.
Posts: 1,453
Default Re: Sony KV1800UB C.R.T. Spots

Quote:
Originally Posted by toshiba tony View Post
What an interesting problem, I spent a lot of years at Sony but never saw this problem. I have dementia now but even the 1810's didn't scare me. So what happens to the tubes on these? We used to get low emission and I seem to remember they were low focus potential sets but this is a new one on me.
New one on me too, it's possible age is causing problems with their construction that the original designers had pushed to a point waaay beyond their expected service life, or adverse storage conditions may be to blame, did many many back in the day, only low emission and the extreme cost of a replacement crt made them ber.
__________________
Picture, sound?, DOOR.
greg_simons is offline   Reply With Quote
Old 23rd Jun 2024, 10:01 pm   #8
simpsons
Octode
 
Join Date: Feb 2007
Location: Harrow, London, UK.
Posts: 1,553
Default Re: Sony KV1800UB C.R.T. Spots

It is down to the chemical formulation and an issue with computer monitors but when recognised as a problem, the formula was changed.

My KV2000 has started to show signs of a cataract with yellowing around the edges. I've also had the black spot issue with an KV1800 now kept for parts whilst the good'n is kept in a low humidity environment. The CRT in this one is too good to muck about.

Chris
simpsons is offline   Reply With Quote
Old 24th Jun 2024, 9:52 am   #9
Mr Hoover
Hexode
 
Mr Hoover's Avatar
 
Join Date: Jan 2007
Location: Faro, Portugal
Posts: 272
Default Re: Sony KV1800UB C.R.T. Spots

I have a 1330UB with spots at the
top right of the screen. It was like that when
I was given it in the late 1990's and has
not got worse since.It could well
have been stored in damp conditions
as had not been used for a while when
it came into my hands.
Mr Hoover is offline   Reply With Quote
Old 24th Jun 2024, 3:20 pm   #10
Welsh Anorak
Dekatron
 
Welsh Anorak's Avatar
 
Join Date: Apr 2005
Location: North Wales, UK.
Posts: 7,044
Default Re: Sony KV1800UB C.R.T. Spots

I had a KV1800 with the inevitable poor tube so it was stored in a shed. A year later and, yes, the same had happened around the edges.
I did offer it around, but as there was undertandably no interest it was disposed of.
__________________
Glyn
www.gdelectronics.wales
Welsh Anorak is online now   Reply With Quote
Old 24th Jun 2024, 7:21 pm   #11
chroma04
Pentode
 
chroma04's Avatar
 
Join Date: Jul 2008
Location: Doncaster, South Yorkshire, UK.
Posts: 119
Default Re: Sony KV1800UB C.R.T. Spots

I'm very interested to hear these comments from other forum members.

My particular set is one which I had been keen to acquire once again, due to having owned one as a teenager in the early 1990's. I suppose they were considered to be an old set even back then!

Adrian.
__________________
Chroma 04
chroma04 is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 11:41 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2024, Paul Stenning.