Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Solid State CRT Televisions

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 06-19-2017, 09:58 PM
MIPS's Avatar
MIPS MIPS is offline
VideoKarma Member
 
Join Date: Jun 2014
Location: West Canadia
Posts: 600
Sony KP-7220 Tragedy

Oh man, I didn't want to make this thread. I'm sorry.

This was seen on the Bellingham Craigslist last month for $60, sold as "working".
No remote or top glass but came with the base projection unit and the massive 72" silver screen with a few small nicks and bruises but still in great shape.
I managed to persuade a friend in the Everett area to pay and pick it up for me and hold onto it until I could collect it this past weekend. When I arrived he had already unbolted the legs from the screen and everything was waiting in the garage. The projection unit was loaded in the car and after verifying that the screen wouldn't scratch or mar up by being handled it was carefully wrapped in a tarp and strapped to the roof with the screen facing down.



The drive was relatively uneventful and the screen didn't make any attempts to make an escape from the roof rack. Unloaded it all late last night and this afternoon managed to unwrap the screen and better look over the projector.

Son of a.....




The silver coating is ruined! The tarp must of been way more abrasive than I expected it to be and simply wrecked the reflective surface. I knew I should of padded the face with sheets of foam before wrapping it up. No gouges however but no idea how to resurface that.




The projector from the outside showed signs of wear (and the above missing components) but all I was going to do was put my Pioneer VP-1000 on top and call it good so that was fine. Inside there was a little bit of dust but everything seemed okay.
Plugged it in and pushed the power button. Heard the high voltage come up, audio came up and saw red and green but the blue was stone dead. Was not able to see if the filament was lit because as I reached to toggle the NORMAL/TEST switch a small lytic cap on the rear board of the red gun puked its guts and I killed the power.
Add insult to injury I seem to of misplaced the four bolts that you used to attach the screen to the stand, so nothing in the set right now actually "works". Additionally, this is another one of those products where it seems you can find the service manual online in PDF form, but you gotta pay to download it. My usual sources of manuals do not seem to have it either. 1200km for another project.

Here's a photo of what the set and (smaller model) screen looked like when it WAS all together and working.



Last edited by MIPS; 06-19-2017 at 10:58 PM.
Reply With Quote
  #2  
Old 06-20-2017, 08:32 AM
Electronic M's Avatar
Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 10,498
Way too late for this advice I know, but: A favorite packing material of mine is 4'x8'( x2" or x3/4") sheets of Styrofoam insulation from the local hardware stores....If you cut one slightly bigger than the screen set it face down on it and taped the sides of the screen frame to the foam the screen likely would have fared better.

When I was a wee lad one a my kin had such a beast in their basement rec room, can't remember the make or model, but I thought it was more interesting than the stuff they were watching on it.

Best of luck getting it working.
__________________
Tom C.

What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4

Reading between the scan lines since the mid 2000's.
Reply With Quote
  #3  
Old 06-20-2017, 11:00 AM
andy's Avatar
andy andy is offline
VideoKarma Member
 
Join Date: Jul 2002
Location: Austin, TX
Posts: 4,004
The rule with these silver screens it that nothing should ever touch it. Even cleaning them is best avoided except when absolutely necessary. The surface has a fine texture which is essential. I'm not sure how you would be able to resurface it, but I'd love to find a way since they almost always have some scratches.

I have a PDF of the service manual if you still haven't found it.

I have a KP-5020 which is mostly just used as a table, but I do bring out the screen sometimes for parties/holidays.

It's not a bad set, but it's severely handicapped by the lack of a video input. It has a hot chassis, so adding one isn't straightforward. There's actually a spot on one of the boards for an A/V input (complete with optoisolators), but it would be a big project to figure out all the component values. Maybe there was a Japanese version with the input?

I did add a digital comb filter module from an old Sony 32" TV chassis to improve the picture resolution and reduce false color.

Last edited by andy; 06-20-2017 at 11:56 AM.
Reply With Quote
  #4  
Old 06-20-2017, 12:23 PM
rpm1200's Avatar
rpm1200 rpm1200 is offline
VideoKarma Member
 
Join Date: Jan 2006
Location: Rochester, NY
Posts: 240
Since you have nothing to lose at this point, maybe you can try repainting the screen using the silver paint that is designed for creating screens on walls. I assume the two issues there would be getting the surface as smooth as possible, and ensuring that the paint would adhere to the screen.

I'm sure you will be able to get the electronics fixed up and replace the missing hardware.
Reply With Quote
  #5  
Old 06-20-2017, 02:23 PM
centralradio centralradio is offline
VideoKarma Member
 
Join Date: Feb 2014
Posts: 994
Nice catch.I have a curved screen here from a Sears set which was destroyed from moving around place to place.Your base unit looks clean.Probably just beam it on to a white wall for now.The big tragedy with those sets are CRT burn ins.

If you dont have it yet. Heres the free service manual for your set from freeservicemanuals.info .Looks like this manual is for worldwide multi broadcast format set.

https://freeservicemanuals.info/en/s...PSE/KP7220PSE/

Last edited by centralradio; 06-20-2017 at 02:36 PM.
Reply With Quote
Audiokarma
  #6  
Old 06-21-2017, 06:34 PM
TVTim's Avatar
TVTim TVTim is offline
VideoKarma Member
 
Join Date: Nov 2013
Location: Near Harrisburg, PA
Posts: 546
How about an old movie screen? I see them on Craigslist from time to time.
Reply With Quote
  #7  
Old 06-22-2017, 08:55 AM
MIPS's Avatar
MIPS MIPS is offline
VideoKarma Member
 
Join Date: Jun 2014
Location: West Canadia
Posts: 600
Those are all fabric based. This screen is a giant sheet of molded plastic with a metal film adhered over it.

Quote:
If you dont have it yet. Heres the free service manual for your set from freeservicemanuals.info .Looks like this manual is for worldwide multi broadcast format set.
I'm looking at that page with my ad blocker on and off and I cannot see the actual download link.
Reply With Quote
  #8  
Old 06-22-2017, 12:59 PM
andy's Avatar
andy andy is offline
VideoKarma Member
 
Join Date: Jul 2002
Location: Austin, TX
Posts: 4,004
Getting it to converge and focus on a flat screen would be difficult. The dynamic convergence controls might not have enough range. Also, they depend on the ultra high gain of the curved screen to be bright enough.

These types of screens used to be common, so one might turn up eventually. If you find one that's a different size, you can readjust it to work. The lenses do have focus adjustments, and you can change the angle of the red and blue CRTs by installing spacers. I briefly had my 5020 projecting onto an 80" Advent screen until I bought an NEC data grade projector that can do HD.
Reply With Quote
  #9  
Old 06-22-2017, 06:01 PM
centralradio centralradio is offline
VideoKarma Member
 
Join Date: Feb 2014
Posts: 994
Quote:
Originally Posted by TVTim View Post
How about an old movie screen? I see them on Craigslist from time to time.
I was thinking the same thing.

Quote:
Originally Posted by MIPS View Post
Those are all fabric based. This screen is a giant sheet of molded plastic with a metal film adhered over it.


I'm looking at that page with my ad blocker on and off and I cannot see the actual download link.
With Firefox with cookies off and ABP on.Its OK.

Where it says.

Brand Sony
Type a KP-5020PSE "click here".
Reply With Quote
  #10  
Old 06-22-2017, 08:26 PM
MIPS's Avatar
MIPS MIPS is offline
VideoKarma Member
 
Join Date: Jun 2014
Location: West Canadia
Posts: 600
Ah, there it was. It was hiding on me.
Okay I'll take a few days to skim over the book and work from there. Until the set works I'm sidelining the screen.
Reply With Quote
Audiokarma
  #11  
Old 02-21-2019, 03:49 PM
UncleWill UncleWill is offline
VideoKarma Member
 
Join Date: Jan 2019
Posts: 1
I joined this website so I could share this with you. I have a KP-5020. This is a NOS screen, close in size to yours. Hope this helps:
https://www.ebay.com/itm/Panasonic-C...ci~I:rk:7:pf:0
Reply With Quote
  #12  
Old 02-22-2019, 04:43 PM
mr_rye89's Avatar
mr_rye89 mr_rye89 is offline
VideoKarma Member
 
Join Date: Jul 2015
Posts: 118
I wish I was closer to Canada, or you closer to New Mexico, I have a KP-7220 and screen (not in great shape but better than yours, and it needs legs) That I'm trying to find a good home for. I cleaned up and changed the glycol, and the set works good.

These sets can work with a flat screen, just not well. There's enough room for adjustment on the convergence board to make it work, but the guns aren't moveable so you cant really do schefmplug adjustments (movements for those who do large format photography) and get a sharp image.
Reply With Quote
  #13  
Old 02-22-2019, 08:30 PM
MIPS's Avatar
MIPS MIPS is offline
VideoKarma Member
 
Join Date: Jun 2014
Location: West Canadia
Posts: 600
Thank you for the link however it would be impossible for me to transport it.
The previous screen had to be strapped to the roof of a borrowed car and even then the wind made a mess. It's the middle of winter and we are getting slammed with storms so even though this one is nice, minty and clean in a transport carton I'd have no way to waterproof it for the trip and the water and road conditions would ruin it.
I'm feeling a bit more compelled to just remove the curved screen from the bezel and leave it to a paint shop to reapply a suitable coating.

Last edited by MIPS; 02-22-2019 at 08:41 PM.
Reply With Quote
  #14  
Old 02-23-2019, 12:39 AM
MadMan's Avatar
MadMan MadMan is offline
'A Disgusting Brony'
 
Join Date: Oct 2016
Location: Chicago
Posts: 729
I think TVTim's on the right track. I'm not sure, but I'd imagine the surface of your screen is likely the same as any high quality projection screen, but on plastic instead of fabric. As your screen is ruined, I would buy a good used projection screen as big as or bigger than the screen. Then, sand down the surface of your messed up screen, make it flat and smooth, cut the 'new' screen to fit, and glue it over the old screen.

The curvature might present a problem, though.

I have an old projection screen, and if you look closely at the projection surface, it looks like reflective silver sand paper. I'm imagining this tv screen is a similar surface. I also have a modern (cheap) projection screen, which if you look at the surface, literally just looks like semi-gloss white paint. Definitely cheap.

Anyhow, some of that paint-on screen paint looks like it might be good. You could experiment with some of that, I suppose.
Reply With Quote
  #15  
Old 02-23-2019, 09:56 AM
rsasnett rsasnett is offline
VideoKarma Member
 
Join Date: Nov 2012
Posts: 2
screen paint

You could try refinishing the screen using paint designed for projection systems. They come in several different colors and gloss levels, from white to medium-gray, and reportedly can deliver results comparable to professional Da-Lite fabric screens. The custom products like Screen Goo are very expensive (like $120 to cover a 4x6 screen) but reliable: here it is at B&H Photo. Or there are DIY solutions where people have mixed their own formulas using home-store paints: here's the Beginner's Guide from the AVSForum.
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:45 AM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
ęCopyright 2012 VideoKarma.org, All rights reserved.