Moon Patrol Monitor Ripple Wave Woes

That is likely the dag gnd strap. Connects metal spring thingy that touches dag coating on crt and gnd on neck board. It should be attached. It is often cut to remove e chassis from monitor without desoldering from. Neck board.
 
That is likely the dag gnd strap. Connects metal spring thingy that touches dag coating on crt and gnd on neck board. It should be attached. It is often cut to remove e chassis from monitor without desoldering from. Neck board.
Okay I definitely have them connected and spliced.

After reading your linked thread and thinking about it, I still believe I need a greater level of understanding. I see those talking about connecting FG & GND and I see those saying just disconnect a GND connection altogether. I want to make sure I fully understand this both for Moon Patrol and posterity.
 
Can you take a picture of the entire back inside cabinet? Williams games usually have a piece of silver gnd braid connected to one of the rear corners of the monitor frame.


Also try unplugging marquee light before we go too far down this rabbit hole.
 
Ah okay, so FG is the braid running through the entire cabinet? I'm about to put my toddler to bed. Unfortunately I'll have to get back to the cabinet probably later or tomorrow. You're saying disconnect that from the frame, I got it now. GND to PCB different than the grounding on the monitor which is Earth
 
Can you take a picture of the entire back inside cabinet? Williams games usually have a piece of silver gnd braid connected to one of the rear corners of the monitor frame.


Also try unplugging marquee light before we go too far down this rabbit hole.
Oh okay no, interesting, you say you disconnected FG entirely on switcher in that Pac cab from that thread a decade ago and had zero problems.

I'll also disconnect the marquee light first when I get the chance.
 
I don't know if anyone is making axial replacements for those or if we're relegated to doing clumsy jumper wires like Bob Roberts again now that GPE is gone. one of the benefits to me not fixing those games anymore is I don't have to necessarily concern myself with this that much. lol
yes i have axials made 105c every year since 2016 and just got an order in last month so always new stock and way more values then anyone else has ever carried including mouser/digikey. if there is a value i don't have you let me know and i will get it if its needed.... ;)
 
Update:

Disconnecting marquee light yielded no change. I assume that was to test if marquee was robbing AC power that should be going to the monitor?

Anyway, switcher, FWIW, that works in tandem with the linear, has no current connection on FG. Logic GND sees the yellow and yellow/white at the terminal.

Re-pinned 15 pin also shown at 4J1. No burn. Solid. Earth ground braid I pulled off the frame but also no change. Worth noting I also removed the degausser connector on the chassis too.
 

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you don't need the linear power supply at all if you're using a switching mode power supply. you just need to port the yellow wires from the coin door plug of the old power supply to +/-5V (prefer -5V) and ground to restore the GI lamp connections and the black-orange coin door ground wire to ground to make the test panel and coin switches work again. you'll have issues with the CMOS corrupting using a switcher however.

the linear power supply overhaul is a fairly simple procedure and will gain you some experience soldering and the game will appreciate it too
 
you don't need the linear power supply at all if you're using a switching mode power supply. you just need to port the yellow wires from the coin door plug of the old power supply to +/-5V (prefer -5V) and ground to restore the GI lamp connections and the black-orange coin door ground wire to ground to make the test panel and coin switches work again. you'll have issues with the CMOS corrupting using a switcher however.

the linear power supply overhaul is a fairly simple procedure and will gain you some experience soldering and the game will appreciate it too
Such is very true…I did eliminate the need entirely on my Robotron and also put in a lithium battery, hasn't failed me thus far…what I noticed upon further inspection in all this was that it looked like someone had already done just this on the switcher by cutting coin door wires on the IDC at the 6 pin and put them on -5v and GND. I had done something similar on my SEGA Turbo.

But monitor still performing mascot for Wavy Lays potato chips. ☹️
 
has anyone suggested adjusting H. Hold? cause that's what that usually is
Yeah earlier in the thread I fixed the slight horizontal collapse across the top with H Hold adjustment.

The fast, oscillating pulse through the raster scan still persisted. I suppose it can't hurt to turn the pot as far as it can go to see where I end up on that.
 
Yeah earlier in the thread I fixed the slight horizontal collapse across the top with H Hold adjustment.

The fast, oscillating pulse through the raster scan still persisted. I suppose it can't hurt to turn the pot as far as it can go to see where I end up on that.
a) that's not horizontal collapse (you can call it wave or curl) b) if the monitor hasn't been serviced then it will need it
 
a) that's not horizontal collapse (you can call it wave or curl) b) if the monitor hasn't been serviced then it will need it.
Good to know, thanks.

Chassis was fully serviced, works flawlessly in other games.
 
Have you hooked up a different monitor to the moon patrol? When I built my moon patrol cabaret, I went through three different 13"monitors before I found one that didn't give me geometry, sync or ripple issues. Though 4900s are usually what's found in Williams games, K 7000s work just fine.
 
Have you hooked up a different monitor to the moon patrol? When I built my moon patrol cabaret, I went through three different 13"monitors before I found one that didn't give me geometry, sync or ripple issues. Though 4900s are usually what's found in Williams games, K 7000s work just fine.
That I certainly haven't done. That's good intel.
 
I was able to capture the nature of the issue more adequately with this slo-mo video on my iPhone 16 Pro Max. It doesn't last long because it records at 120 FPS but you can catch it right at the beginning before the camera leaves the CRT in the dust. In the literal 1st second you can see the great speed of the wave and see it less so as the video goes on because of the refresh rate. The best indication is when you follow the left most mountain on the parallax scrolling.

 
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Going to tie FG to GND on the switcher as my next attempt on this one, coming back to this after a couple other things in the lineup
 
The bridge we will use to cross into battle against the forces of interference. 🫡🥺 Will this flanking route be enough for us to take the great ripple wave by surprise and eliminate its evil forever? Stay tuned…
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Spoiler alert lol: we lost the battle…significant casualties, forced to retreat, see the horror in the battle footage below…😭

 
Wonder if I should wire a connection between GND on the switcher and a screw plate where the linear supply is mounted instead of just FG to GND on the switcher terminal block… 🤔 might just have a ground loop on the former because of the hybrid power supply. In any event I am actually waiting on an entirely new switching power supply as the one currently in the cabinet looks a bit dated and I'm just going to bring everything over.
 
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