Wells WG D9200 No OSD On Screen Display Issue

Keroppi

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Hi all, I just picked up a GT cab with an original D9200 (not D9204/etc) in it. It displays fine (surprisingly) but the OSD doesn't work.

The 'No signal' message DOES show up when no signal is connected just fine, and cycles through all the colors.

The control board does function, and the software responds, as I managed to (eventually) blindly press buttons and get to (and adjust) the H-POS and contrast menus...I understand this to be controlled on the neckboard, but I am finding conflicting info on it. WG troubleshooting guide points at IC201, but other forum posts such as http://forum.arcadecontrols.com/index.php?topic=105867.0 indicate that it is IC202. Can anyone verify what to check/which it is, and a source/part # for the chip?

Also worth noting, although I can blindly go through the menus, SEL does NOT degauss the tube.

Could the "corrupt EEPROM" issue I keep reading about cause this behavior? If so, could someone walk me through the SEL+DOWN factory memory recall (blind, by number of button presses) Thanks!!!
 
To anyone who knows:

1) It appears that the OSD data/commands are fed into IC202 pins 7-8 by IC101 pins 36-37...what sort of signals should I see coming through here to assess that IC101 is outputting to IC202 properly?

2) Is the 'NO SIGNAL' message overlay'd by IC202? If so, wouldn't that mean that IC202 can clearly bring pin 4 high? I would *assume* that if IC202 creates the message, it would do so by not detecting the V-SYNC signal from pin 1, which would mean IC202 failed on the input side or is not being fed correctly by IC101?

3) Since the non-working degauss circuit is controlled from IC101 pin 1, should I suspect IC101?
 
I checked it again today, and the menu *does* actually display, but it is shifted to the very bottom of the screen, to the point you can see the 'MAIN MENU' text and nothing else. All of the sub menus and the rest of the main menu are off of the screen. If I enter the service mode, the display changes and "collapses" the very bottom portion of the display, so the visible menu area becomes a distorted line.

The display does not fill the screen vertically, and the vertical position is all the way at the top. These *might* be affecting the menu display. I'd like to try adjusting the V-SIZE and V-POSITION to fill the screen, but I can't seem to get to those menus blind ...could someone *please* walk me to/through it blind? It appears that the menus (in order) are:

CONTRAST
BRIGHTNESS
H-POS
H-SIZE
V-POS
V-SIZE
PIN
TRAP
GAIN
R
G
B
RE (Recall?)

...But I don't know where it starts, or any sub messages or confirm screens or anything. I need something like:
*MENU* <- Enters main menu, which item is already selected?
*DOWN* <- Item? Is it ordered as I listed?
*DOWN* <- (How many times?)
*DOWN* <- V-POS (or V-SIZE)
*SEL* <- Into Sub-menu
*Up* or *DOWN* to adjust
*MENU* <- Out of Sub-menu
*MENU* <- Out of main menu? Any confirm/save dialog or anything?

Is that about right?
Can you change the OSD position in the Service Menu? If so, I Really just need that walk-through. Anyone who can help, it would be greatly appreciated. Thanks!!
 
50 people look at this, and not one responds...are these just that bad to work on (hence why Chad doesn't fix them?) or should I just feel unloved?

There definitely isn't an OSD position in the service menu...basically the same as the std menu+bias/gain.

I managed to fumble through some of the menus today blind, and increasing the V-SIZE made another problem apparent: The bottom 2 inches or so of the screen have collapse (vertical deflection problem?) and I can faintly see one retrace line at the bottom of the displayed raster...when I would extend the raster into the area, all of the added raster would add into one line. Evidently the previous owners shrunk the raster to fit within the "good" area...Entering service mode calls the factory settings, which fill the screen, hence why the menu would shrink to one line at the bottom...the menu is almost off the screen regardless, it just can't display the raster across the whole tube correctly on top of that.

I found this service bulletin:



TECHNICAL SERVICE BULLETIN
WELLS GARDNER MONITOR
Model: WGM2792-U0TS09B

This service bulletin addresses the following field reported problems with the current Wells Gardner digital monitor chassis.

Symptoms:

The upper portion of the display shows retrace lines during active video display.
The upper portion of the display appears "Dim" and/or "Washed Out" when compared to the lower portion of the display.
The lower portion of the display shows retrace lines during active video display.
The lower portion of the display appears "Dim" and/or "Washed Out" when compared to the upper portion of the display.
The above listed symptoms appear randomly, often after the unit has been operating for a short amount of time. The symptoms may appear and disappear during normal operation.

Analysis:

The electrolytic capacitors in the vertical sweep circuitry have failed. Symptoms 1 and 2 are a result of C306 (2200uF, 25V) failing. Symptoms 3 and 4 are a result of C314 (2200uF, 16V) failing. Both capacitors are located adjacent to the vertical sweep transistor heat sink. The failure is a result of the electrolytic fluid inside the capacitor boiling and/or out gassing, causing the capacitance to decrease. This boiling and/or out gassing also results in a visual deformation the capacitor case. The deformation is typically exhibited by a "Doming" of the top of the capacitor case.


Resolution:

Remove capacitors C306, C308 and C314. Replace C306 and C314 with new capacitors (2200uF, 25V, 105 degrees C. temp) and C308 (220uF, 50V, 105 degrees C. temp.).




To anyone who would answer:

Is there any other caps to replace or things to check that you guys could recommend based on the prognosis?

And do you think the 2 could be related, vertical deflection issue and an OSD with improper (vertical) position?

Thanks!
 
And do you think the 2 could be related, vertical deflection issue and an OSD with improper (vertical) position?

The OSD is towards the bottom of the screen normally, so, sure, if the portion of the raster the OSD is supposed to be in is offscreen, then you definitely need to fix your deflection problem first.

I have two working D9204s here at work if you need something referenced.
 
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