[hokiefan]

Hi everyone!


We have an old sony kp-7220 projector and the original screen that came with it. In fact we are the original owners of it! My question is the red crt seems to be over powering the picture, the blacks are now tinted red. I have attempted to turn back the brightness on the red gun using the controls inside the unit, but it is turned down all the way. Any suggestions?


No one will work on the unit, or will for lots of $$$$. I like fiddling with electronics so I might play with it at some point if the red gets worse. Also if anyone here is in the maryland area and is a expert at this stuff and would like to work on it as a hobby project i would love to have someone do it. I guess its more of a collectors item now, but the picture is really great for the age.


If anyone knows where i could get schematics or a service manual for this model (sony kp-7220) i'd really appreciate it.


Thanks!


Rich

 

[Mike Williams]

Im not an expert but it sounds like what you are experiencing wear on the crts. The remedy would be to r&r with new or newer ones. With the prices of 1272's and similar vintage, units that might be a better way to go.


MRW

 

[MYoung]

How about some cyan shades?


Hmm, sounds like you need to calibrate the G2 controls. I haven't a clue about that projector. An easy fix would be to try some ND (neutral density) filters over the red lens. Though that's a pretty chinsy fix.


As Mike said, you could just get a newer CRT pj. You can retire your old one or use it as a beater for video games and TV.

 

[Curt Palme]

It's been 10 years since I worked on one of these.


There are G2 controls in these units I think, alongside the focus controls on a small PC board(going from memory!)


If you've adjusted those, then I think there are sub brightnes controls on the video board, I seem to remember that Sony labelled all of the trimpots on the boards, so you should be able to find them.


It might just be that the G and B tubes are getting weak, they are getting to be about 20 years old after all..


Curt

 

[hokiefan]

Thanks for the great suggestions. I will take another look inside to try and find these "g2" controls. The ones I have been playing with are on a large circuit board with trim pots for a range of things like hor, vert control, etc. Theres probably about 20 or so of them. Would that be the video board? You are right, most of the controls are labeled. I believe the green or blue tube was replaced awhile ago (maybe 10yrs?) because it broke, but i dont remember the red one being replaced.


Is there a good place to get a ND filter? online? I'm trying to keep this unit alive since my parents are going to get rid of it soon, and I wouldnt mind having a big screen to watch movies on. When you're 10' away from the screen you dont notice the lower res picture as much. Right now I have a zenith 27" 4:3 hdtv.


Thanks again for the tips!


Rich

 

[bravozulu]

Have a look at this site: http://www.eboyztoyz.net/1031q/pages...tup_Guide.html


Its a setup guide for a Sony 1031q projector - although its for a different projector, the basic explanations of what you need to do to set up your projector will still apply. Read the method for correctly setting G2, then you'll have an idea of how to tweak your machine.


And, of course, ask this forum if you get stuck.


Good luck!


Pete