Ceronix 1490 for IGT 701 draw poker text not aligned.

[Asurber]

I just got this running and have a very minor problem that I was wondering if you could help me with. The black above the numbers and letters towards the top of the CRT is a bit off, the payout number is also not centered vertically in the black. I tried the pots on the monitor and centered it nicely on the screen but it just moves the whole screen with these. I think it might be convergence issues?

[Chris-socal]

Hello:
Another fun machine, we have seen a number of these lately.
Regarding the question about the black above the numbers and letters toward the top of the CRT....are you sure that just isn't the monitor bezel?  It's the plastic trim piece inside the door that keeps light from the internal fixtures from washing out the picture. It also keeps fingers and such things from poking into a machine. If that isn't perfectly centered it will make the image seem a little

Regarding the question about the alignment, it seems if this was a convergence issue it would be off everywhere. Plus, the convergence rings adjust RGB so for it to impact black wouldn't that mean all 3 colors are off? Meaning, all the black should be off, even the black suits of the cards.
I'm not sure about the alignment of the payout background, it does look off but I'm not sure how you would adjust that, is it possibly a problem with the video circuitry on the MPU? It would be interesting to stick another working 1490 or 1492 and see if anything changes.

I'm leaning toward image source. Let's see what others have to say.

Chris

[Asurber]

It's not the bezel, I noticed that black is also under the 25 cent text. Sounds like the vertical edges of the screen are controlled by the horizontal edges of the CRT yoke, do i have that right?

[Chris-socal]

Could be, that's getting pretty technical, the rings usually have paint on them so you can see if they have moved. Is it possible the yoke shifted??
Here is an excerpt from a TPG manual, it's basically answering why block patterns are used to indicate circuit health, it would be interesting to connect a TPG to your monitor, I have worked on boards that exhibit what's referred to as a tombstone effect (not quite square). Since I am borrowing their text, I will also include a link to their device at the very bottom:

The CHECKER pattern displays alternating black and white/red/green/blue boxes as in a
checker board.
This pattern is useful in checking the high voltage regulation of CRT power supply circuits.
Poor regulation results in trapezoidal looking pattern. For CRT type monitors with
insufficient power supply regulation can result in the corners of each box do not touch each
other as they should. This effect can sometimes be reduced by lowering the brightness or
contrast settings.
This pattern is also useful for checking ringing of the video signal as the signal transitions
from black to white. The abrupt, maximum change in CRT video drive current produced by
this pattern should not cause the voltage supplied to the video drive circuit to change in
display device with good voltage regulation. For display device with power supply that does
not have good regulation, softening or ringing in the pattern transitions can result.

https://www.arcade-museum.com/manuals-test-equipment/MT830A_User_Manual.pdf
https://www.ebay.com/itm/323882801012?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=Q5eZpeTKQcq&sssrc=2047675&ssuid=emm0sFORS4-&widget_ver=artemis&media=COPY
Just know, this device covers CGA up to VGA but it doesn't appear there is an option to invert colors. As such, RGB will not appear as RGB on Ceronix 1490, 1492, RGB1401 and other monitors that use an inverted color signal.
For inverted monitors I personally use a Craftymech TPG which covers Standard and Medium resolution only.

Chris

[Asurber]

Thanks Chris, so funny because my dad used to have a TV repair shop in the 60's, too bad I wasn't older and more interested! I'm really interested now and think my next purchase will be a Craftymech TPG.