toei arcade monitor, no eht?

[phreak97]

hey all, i have just taken a monitor out of an snk photo cabinet for use in my playchoice cab, but the screen stays dead, i get a white flash when it's turned off, sometime i think i can see the game in the flash, but its hard to tell. anyway, i went to discharge the tube to take the chassis out, and there was no discharge, i then turned it on and off incase it has a self discharge feature, and traid again before it would have had a chance, still no spark. i think the eht line isnt coming on...

what should i look for to test? im probably just going to replace all the caps, theres only about 30 on the whole board.. but none of them look sad at all.

anything more specific than blindly replacing caps?

thanks

[NeWmAn]

I have a monitor with the same symptoms: dead but when you power it off sometimes it shows a flash of light.
In my case it had a dead HT (and other problems... I'm still waiting for parts to finish the repair), maybe you have the same problem?

BTW I've read that Nintendo used non standard signals in their arcade monitors. Can the playchoice board be used without a color inverter?

[phreak97]

which parts of yours are dead? and what am i measuring for on mine? it could easily be the same problem.

i already have a colour inverter as the cabinet is a generic cabaret which i wired up for playchoice.

[NeWmAn]

Mine is not a Toei, I just said that I had the same symptom.
You should check the big transistor that's bolted to a heatsink, you should check if it is shorted.
I can't help you the part number/name because I don't have a schematic.

[phreak97]

well.. i replaced most of the caps, unfortunately some of the ones near the eht transformer were too high voltage for the store i went to, ill check the transistor though..

[viletim]

I have an old Toei monitor around here somewhere (my only arcade monitor). Bloody unreliable thing, it failed twice within a month of buying it. It's very simple however, should be no problem to repair it no matter what's wrong.

It does seem from your post that you don't know the first thing about repairing monitors... Is the power supply working? Is the horizontal deflection working (you'd be able to hear it)? Is there a raster (turn up the screen bias)?

Read through http://www.repairfaq.org/samnew/tvfaq.htm if you haven't already. An arcade monitor is just a simplified TV.

[phreak97]

yeah, i really dont know the first thing:P

you can hear the monitor is on, so i guess the power supply is on, and it's probably the horizontal deflection noise.. i tried turning up the screen voltage to see if i got retrace lines or anything and i dont, the screen flashes white round the sides when i plug power into it and the whole thing flashes white when i unplug it, any other time it stays dead black like when it's off. what should i try next?

ill have a read through that link when i finish typing this.

edit:
theres alot of information there, but without knowing my way around a monitor chassis i cant get too much out of it. by the way i've learned how to discharge the tube both the proper way and the hard way (getting too close:P), so dont worry about me dying.

while we're on the topic, i've got a commodore 1084 monitor with a grey single horizontal line which doesnt seem to change at all when different video is fed to it, but i want to fix the toei monitor first, if i can get that done i might move this thread onto the 1084.

[viletim]

phreak97,

Maybe your vertical section has a fault. That would explain a flash at startup, a working horizontal section and no raster. The vertical section is outputing DC to the yoke (very bad for it) and there raster is just a vertical line and at the extreme upper or lower part of the deflecton range (so you won't see it).

Check the vertical output stage for short circuits.

[phreak97]

viletim, if i take some photos of the chassis, can you point out the components most likely at fault? all ill be doing is following the vertical section of the yoke backwards and hoping that it's leading me through the vertical output stage.. i'm really quite useless inside a monitor.. once i know the fault i can fix it, but i'm stumbling around blindly till then.

what reason is there for me not getting a pop or anything when attempting to discharge the tube? does it not charge if the vertical is dead?

edit:

i have taken some photos, they can be viewed Here

i made them as high res as i could, not bad for a phone.