OMG what I have gotten myself into! (monitor style)

smalltownguy2

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OMG what I have gotten myself into! (monitor style)

Thanks to kjeffrey, I'm now the proud owner of 5 more monitors, and a spare chassis. Good lord what have I done. Guess I'll be diving into some monitor repair.

Monitor 1, yet unidentified. Is this an early Wells Gardner?

CIMG6170.jpg


Monitor two, a Wells K7xxx series thin neck tube, and chassis:

CIMG6173.jpg


CIMG6172.jpg


Monitor 3, a Nanao 100v with Sega markings:

CIMG6174.jpg


More to follow in next post....
 
Monitor #4, some weird off brand I can't ID, with Pac burn and Pac brackets on the frame:

CIMG6176.jpg


CIMG6177.jpg


Monitor # 5, a Makvision, minty fresh!

CIMG6168.jpg


And, an extra 25" K7xxx chassis:

CIMG6171.jpg


Now, to figure out what to do with all of them???

Time to start troubleshooting!
 
Wow.. I know the feeling all to well actually. I too recently scored on 5 - 25'' monitors. 4 out of the 5 work. Sent em off for some repairs (another KLOV'r). In the short time that i've had them i've already found projects for 3 of them.

Eventually I'm finding things to use them for.. so first thing is first.. get em working and then the projects will come to you. Or you could always turn around and re-sell them to others who may need em.
 
That first one looks exactly like the WG4906 that came out of my Ms. Pac-man
 
Your Nanao monitor is the less common MC-2030-S model....slightly different from the common MC-2000-S.

Edward
 
Update to this thead: I was working on my Dig Dug cabinet restore project this weekend, doing some monitor work. I had a vertical mounted Wells Gardner 19K7951 that I cracked the neck on 2 autumns ago and had swapped in a new tube from a 19" TV. I'd used this monitor a few times, but it had some gauss in it that I couldn't get out. No amount of degaussing was fixing the issue. I've concluded that the TV tube that I chose was not 100% compatible with my chassis/yoke.

Sitting next to me was monitor number two, the tube mounted horizontally. Kjeffrey told me that the tube had no blue. I hooked up the rejuvenator and found that the blue gun was nearly completely unresponsive, and shorted. I snapped it a few times with the 'remove shorts' function and tapped on a neck a bit with the plastic handle of my screwdriver during clean/restore and heard a loud pop and sizzle, and then the blue gun came back to life. I had to shoot it three times with the rejuvenation treatment before the needle remained in the green long enough to be acceptable. I went ahead and did a clean/restore on the other two guns while I was at it, and re-calibrated the tracking and and cutoff on all 3 guns. The end result was a very nice looking picture with my 19K7951 chassis. So, I decided to swap frames and chassis and now I'm getting a very nice picture with no gauss issues:

IMG_9405.jpg


Once I get the K7xxx chassis repaired, I'll see how it looks on the TV donor tube in the horizontal mount monitor I swapped. If I can't de-gauss it properly, I'll probably have to give up on that tube and try swapping for another in that frame.
 
OK, I dug into the Makvision monitor today. Monitor was missing the neckboard ground connector, so I added one. It was also missing the 4A 250v fuse, so I threw one in there.

One more weird thing with this monitor: when I went to plug it in, my video connector on my JAMMA test rig didn't fit. What I mean by that is that it's backwards!

See here:

IMG_2493.jpg


If you look closely, you'll see that the video input header connector is oriented backwards, compared to a standard input on my Wells Gardner K7xxx chassis:

IMG_2494.jpg


What do I do? Turn the connector around and plug it in the way it fits? (against the screenprinting designations)?

Or do I de-pin my JAMMA harnesss input connector and re-pin it according to the silkscreen on the Makvision chassis?

Can I damage the chassis by hooking it up backwards? Essentially I'd probably be grounding the green or blue circuit, and sending the red signal up the sync line if I plugged it in backwards.

If I do re-pin my connector, what do the markings mean? R and B I get, but WTF does G7 mean? How about E and S? Do those mean 'E'arth ground and 'S'ync?
 
Most Makvisions that I've worked on have the video connector pinned in reverse.....I don't know what they were thinking. You don't need to re-pin your connector. I just bend the locking lip out a hair and shove the video connector on. The lip flexes enough to do this.

Edward

EDIIT: forgot to answer your question...R = red, G7 = green (who knows why there's a little "7" there), B = blue, E = ground, S = negative composite sync. This is exact as the industry standard for video comnnectors.....except, as you noted.....it's exactly backwards.
 
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Most Makvisions that I've worked on have the video connector pinned in reverse.....I don't know what they were thinking. You don't need to re-pin your connector. I just bend the locking lip out a hair and shove the video connector on. The lip flexes enough to do this.

Edward

EDIIT: forgot to answer your question...R = red, G7 = green (who knows why there's a little "7" there), B = blue, E = ground, S = negative composite sync. This is exact as the industry standard for video comnnectors.....except, as you noted.....it's exactly backwards.

Any reason why I can't just pull the connector off the chassis and rotate 180 degrees?
 
I did some work on the Sampo KGR-1901 last night. (monitor #1)

Chassis was pretty dirty, and there were a few caps out of spec, but not too bad. I chose to leave them to fire it up the first time.

Chassis was missing the fuse, so I put a replacement one in.

Notes on the monitor said that it wouldn't sync, so I reflowed the pins on both the positive and negative video sync connections to be safe.

Powered it on and....

IMG_2496.jpg


Cool. Looks OK to me!
 
I also worked a bit on the Kortek monitor too. The flyback must have a pinhole in it, because it's arcing to the metal cage.

I'll pull the fly off the chassis this weekend and epoxy it to see if I can get the arcing to stop. If I can't, this monitor is probably toast.
 
I also worked a bit on the Kortek monitor too. The flyback must have a pinhole in it, because it's arcing to the metal cage.

I'll pull the fly off the chassis this weekend and epoxy it to see if I can get the arcing to stop. If I can't, this monitor is probably toast.

A lot of those flybacks are around. Get it's number, and start searching....Bob's got some.....and then there's these guys...
http://www.technotronic-dimensions.com/Products2b1.html#targets

Edward
 
Flybacks are really easy to replace and only cost 19$-35$. I would vote to replace the Flyback yourself and save the montior for a game later on.
 
Update to this thread - my Makvision monitor was worked on by Chad over at Arcadecrt.com and I gotta say thanks! You've saved another one!

I'll be using the Makvision in my brand new Ms Pac cabinet since the picture looks really good. The monitor is also strapped to a frame with pac mounting bars already installed, so it was an easy choice.

Also, I have been contacted about the Sampo monitor and it appears I'll be mailing it to another KLOVer to help them save a game they need assistance with. I just found a really nice double walled shipping box at work this week, so I should be able to get that one boxed up and shipped off.

My Nanao monitor has been sent to another user as well.

My Kortek awaits flyback work. I'm going to try and seal up the pinhole with some epoxy. If that doesn't work, Darthi8nt has agreed to send me a NOS flyback he has for it. That should get it back up and running.
 
A lot of those flybacks are around. Get it's number, and start searching....Bob's got some.....and then there's these guys...
http://www.technotronic-dimensions.com/Products2b1.html#targets

Edward

I'm working on the Kortek monitor now. Apparently I've got a Kortek KT-1420A, according to this repair guide:

http://home.comcast.net/~mtpacifico/_kenskorner/files/Kortek_KT-1420A_repair_guide.pdf

The flyback mentioned in that guide is exactly the same as the flyback I have on my chassis, KFS-60291. I'm going to try epoxy on it tonight and let it cure over the weekend.

CIMG6207.jpg


CIMG6203.jpg
 
Success! Burn tested the monitor yesterday and she held up fine. I'm sorry I didn't take a picture of the epoxy repair prior to soldering the flyback back in, but here's the best shot I could get of it installed. You can just make out the glob of epoxy I dabbed on there.

IMG_2724.jpg


And, the money shot. This chassis could probably use caps, but since I'll probably only use it for bench testing, it should be fine.

IMG_2723.jpg


Nice! 5 out of 6 monitors have been saved! Just one more K7xxx chassis to go.
 
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