Dragons Lair bring up. No video at the moment

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We have a working laser disc player and board set. The video colors are way off (mostly just dark looking) so I'm going to be learning about tuning the decoder card and the monitor.

I'll also check some voltages on the monitor mainboard.

Just saw the post from SaminVA regarding the k7000 monitor connection. I'll look into it. I can confirm that we have a 19k7468 model monitor.

One point of concern is the replacement power supply. It's one of the ones below, MD-9916A-24V, but even with the adjustment turned all the way down it's reading about 20% high (ie about 18V instead of 15V). Are these supplies generally reliable? It seems like ab cheap Chinese knockoff. I do not know why original supply is bypassed.

https://m.aliexpress.com/s/item/32735092726.html?trace=storeDetail2msiteDetail#autostay
 

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I'm not so sure its the monitor.
In the first picture, I can see the player's frame/chapter display.
That should never be visible, and it's not even in the correct area of the screen.

You need to connect a TV to the player, and a DVD to the monitor, to determine which one is at fault.

As for the supply, I believe the adjustment pot only affects the +5V line.
 
The power supply is a cheap Chinese knock off but they generally work ok except on particularly power hungry boards (for example they generally won't run a NAOMI or System 16A board)

If you have the ability to replace it with a better power supply, I would. 20% above where you need to be isn't great.

As for the information displayed on the screen, could it be the laserdisc player has been replaced and configured incorrectly? That information is usually a button on the remote control of a DVD player so I assume the same would be true of a laserdisc?
 
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Ld-v1000

This is an original LD-V1000 player. I assumed the characters on screen were part of a debug mode the machine was in, though I'm pretty sure the dip switches were in the ON position. That is the default for both a and b banks?

I found a nice place with lots of laserdisc player info (manuals, schematics, service manuals) and confirmed the external control connector pinot. I definitely had it connected backwards some times on the mainboard side. Given how wacky the connector pinning is I'm sure I'm not the only one. There appears to be no power on the cable, just ground and dio lines so shouldn't be fatal connected wrong.

http://www.dragons-lair-project.com/tech/ldguide/pioneer.asp

I guess I will look at ld-v1000 docs to see what mode displays the track and chapter info.



The power supply is a cheap Chinese knock off but they generally work ok except on particularly power hungry boards (for example they generally won't run a NAOMI or System 16A board)

If you have the ability to replace it with a better power supply, I would. 20% above where you need to be isn't great.

As for the information displayed on the screen, could it be the laserdisc player has been replaced and configured incorrectly? That information is usually a button on the remote control of a DVD player so I assume the same would be true of a laserdisc?
 
Monitor blanking signal for wg ntsc decoder

I had connected a ps2 into the decoder board and saw similar video quality. I should have connected the laser disc to an external monitor ran out of time for the day.

From what I'm reading it sounds like my options are to

1) use electrohome decoder board

2) figure out where on chassis to get blanking signal and connect to wg board. Notes posted below describe where to get tree signal on the 4900 series chassis. Maybe i can find the similar signal on the 7000 series. I doubt the pcb designators will be the same.

http://wood1st.com/Other/WG Monitor NTSC wires.txt

3) modify wg decoder board so blanking signal not required per directions below.

https://www.mikesarcade.com/cgi-bin/spies.cgi?action=url&type=info&page=wg-ntsc.txt

Options 3 and 1 seem much better than 2, which almost certainly would require removing the chassis board.

So to answer a question posed before - this k7000 series monitor does not have the small vertical board pictured.





I'm not so sure its the monitor.
In the first picture, I can see the player's frame/chapter display.
That should never be visible, and it's not even in the correct area of the screen.

You need to connect a TV to the player, and a DVD to the monitor, to determine which one is at fault.

As for the supply, I believe the adjustment pot only affects the +5V line.
 
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