Sony multiscan 500PS

[starfury1]

HI All

Well I got a Sony 21" 500PS..... nice monitor but has now shown a slight problem

The thing is *breathing, with maybe slight barrel distortion
(*for want of a better technical term )

although it is staying in focus.

Also happens at startup
(so ruling out a long thermal issue here)

lastly seems to be happing more so at the bottom then the top (if at all at the top)


Now after doing a bit of searching and reading some of the service manual

This is going to be a fun to pull down and room is a little limited to keep this monster in pieces.

So I am just wondering if anyone who has worked on these babies has advice on whats best to replace or check while I am in there as I am aiming to pull it down replace/check caps solder joints etc.

If I can I would like to replace likely suspects then have them fail a bit further on

At this point its a symptom me thinks and would like to nip it in the bud before it becomes a real fault condition.

Thank you all for any help or advice

Cheers

Err if any one needs the pdf pm me

[ifrythings]

Re: Sony multiscan 500PS

A little late, but to me it sounds like your ABL (Automatic Britness Limiter) line is not able to change completely when it close to the end of the scan time.

It could be a bad opamp or able drive transistor.

Other than that, I'm a bit stump as you are, only other thing I can think of is pour B+ regulation.

[starfury1]

Re: Sony multiscan 500PS

Thanks for the Reply Ifrythings

Yeah did pull it down to have a squizz no obvious signs of cap failure
(not to say they aren't)

There is from what a gather an ic that is known to cause problems with these in the vertical somewhere.
(have to find the info again)

My suspicion was Voltage supply regulation due to caps ...ok well more my hope really... bad caps
As you say could be semiconductor problem (hoping not really) from what I can find they do have some issues in this regard.

or other possibility is dry joint from heat, they do run very warm

Anyway as I said, rather then let it possibly escalate into a more major problem I'm not using it

Was really looking at doing more a shotgun repair/replacement rather then doing the right thing and working out via circuit analysis where the exact problem lies.

Don't really have the space to keep this beast in pieces or a decent work bench setup.

power supply PCB

There are few suspect joints on IC690, 630 which is
standby 8+ dgus, power and heater SW

anyway a few photos for future reference

[starfury1]

Re: Sony multiscan 500PS

OK seem my worse fears may be realized, its possibly not a PSU issue

There is an ic CXA2043Q that is a know issue semiconductor and the symptoms on this web page
match (just "find in" page search 500ps, its near the bottom)

The thing that had me scratching my head a bit about it was the very fact that it was doing it on the lower half and not the top when I was thinking about supply reg problem.

Anyway if I am lucky it might be a surrounding component but knowing my luck it will be the chip.
yet to check location of it in service manual

From what I understand "sometimes DAS alignment is needed, after replacing IC007" (Sony p/n 8-752-078-46)

anyway see what happens

[starfury1]

Re: Sony multiscan 500PS

Just so you know if you didn't...that chips NOT Cheap!

About US$ 75 from one site. (try about $100 possibly plus AU) for CXA2043Q

Yet to really source and check in Oz thought.

I have seen monitors this size going on ebay AU for less then $200 AU "used"
(working or claimed to be)

So just beware if you are looking for a cheap fix on second hand unit off auction sites that has fault listed as vertical or geometry problems that this chip is a good possibility for being the fault.

As to the repair of mine.... well at that price for the chip......I am debating if its really worth while ...still haven't checked other possibilities....stopped when I found that and put it aside for the moment.

Money could be better spent on a TFT screen me thinks