Sony G 500 Multisync Monitor

[Sabot68]

HI all,

  About 12 months ago my Trusty Sony G500 Mulitsync monitor died, I have been using it in an arcade machine build to run MAME.

it was working fine then there was a kind of high pitched squeal and the monitor went black, no pic, no smoke or burnt electronics smell.

I assume its something to do with the high voltage part of the monitor. I have opened it up and had a look around, carefully as i know that the tube and associated caps can hold a charge. I have no experience with CRT's so I am reluctant to poke around too much.

Is there anybody around the SE Qld area (Ipswich) that would be willing to have a look at it?

Or offer any advice on what might be the cause, I have basic electronics knowledge and am handy with a soldering iron and DMM.

Any help would be appreciated

 

Andrew

[darkspr1te]

The first thing i would try is discharge all the caps and replace as many as you can, if it's never had a cap service then it's waaaay overdue for one, high pitch noise is often that failing or the Line output transformer.
There are a few voltages you can check like B+ Hot and B- Hot


Full schematic here
https://elektrotanya.com/sony_cpd-g500.pdf/download.html

it has a voltages list and where to check them, worth a look if you can use you DMM.
some personal advice , watch a few CRT repair video first to learn how to discharge them first before you stick hands inside, also thick rubber gloves wont hurt.

darkspr1te

[wasedadoc]

I would not assume a fault in the HV area.

I would not start by replacing all the electrolytics willy-nilly.

The internal fuse is possibly blown. Replacing that is very unlikely to be the only fix needed.

I would look to the power supply section, Board G. Quite complex, not really something that an unexperienced person will troubleshoot easily. Check Q630 for shorts.

[Sabot68]

yes unless its something obvious trouble shooting this will be a little beyond my skill level.