Sanwa PM1745 no monitor image or neck glow?

For monitor related issues
Post Reply
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

I just recently got my chassis sent back for this from PNL and decided to try and hook it up. I'm still not getting any monitor image. Didn't hear any chassis click and nothing has blown up on it as far as I can tell, but I also don't see any neck glow and when I run my hand over the screen, I do feel static. I've checked and it looks like everything that would be plugged in is plugged in. I used a Nissyo 1550u 120v to 100v step down transformer and I'm still worried about trying it without the transformer. I don't want something on it to blow up again and waste another month and money sending it for repair.

-This is in a Blast City Cabinet with an adapter made for me to connect the arcade machine to the chassis.
-I can still hear the game while it's running.

Edit: Updated to say I do feel static and when I turn the machine off I can see a little flash of light on the screen as if it turned off.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Sanwa PM1745 no monitor image or neck glow?

Post by grantspain »

turn the screen volts up on the flyback to see if you get a raster
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Re: Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

grantspain wrote: July 28th, 2019, 4:27 pm turn the screen volts up on the flyback to see if you get a raster
This may be a stupid question, but does it matter if the machine is turned off while I make that adjustment? If the machine needs to be on, is it okay if I turn it with my bare hands? Asking because a long time ago I remember the tech adjusted that with a screw driver or some other tool, but I don't have one small enough to get in there from the way the chassis is positioned (it's tied in with zip ties just to hold up).
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Sanwa PM1745 no monitor image or neck glow?

Post by grantspain »

its the pot beneath the focus pot on the flyback transformer, you do not need any special tool to adjust it

you can turn it clockwise a little bit without power and see what happens
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Re: Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

Thanks, I’m out right now, but before I left I managed to get a faint image by adjusting the screen pot a bit and the brightness pot on the remote board. Hopefully when I get back I can manage to get something playable.

-Side question has anyone ever tried to run a pandora box 4 on one of these monitors? Nem was telling how that board could’ve been an issue when trying it because of vga I think (but it’s supposed to have cga compatibility at 15khz). I’m running a legit SFA2 board on it at the moment.
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Re: Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

So I got back home and what I'm experiencing so far is that I can briefly get a dim image and then it fades back to unseeable after a minute or two. Any idea what's going on here? The brightness pot will only turn so far and doesn't really help after it fades (was also too washed out when the image was seeable and needed to be dialed down).
Also what does the focus pot do on the flyback compared to the screen pot?

-I still don't notice any neck glow btw, even when I turn the lights off.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Sanwa PM1745 no monitor image or neck glow?

Post by grantspain »

is the tube an original ms2931/2930 or the actual sanwa tube?
not all tube give a noticeable heater glow btw
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Re: Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

It's an actual Sanwa tube. I ordered both the tube and chassis to replace the MS2931.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Sanwa PM1745 no monitor image or neck glow?

Post by grantspain »

did you sent the remote board with the chassis for the repair?
if not perhaps its just a broken pot
Darklightjg1
Please Continue...
Posts: 36
Joined: December 16th, 2018, 1:29 pm
Location: PA
eBay: darklightjg3450
Initials: HIM

Re: Sanwa PM1745 no monitor image or neck glow?

Post by Darklightjg1 »

Yes the remote board was sent as well. I can see the brightness change a bit when the screen is visible, but what would cause it the screen to fade back to black without touching it (happens within 5-10 minutes)?

Edit: I'll add in the detail that the screen doesn't start out visible when I turn the game on either. Like I won't see things like the capcom logo or even the attraction demo and could be well into the character select before it "warms up". Even then it's still incredibly dim... about 20-40% of what you would expect from a brightness display and fades down to like 1% after a certain amount of time. Also the arcade marquee light doesn't turn on like it did when I wasn't using this step down transformer. However, it's the farthest I've gotten with a monitor in the past 8-10 months without it blowing up or just not displaying anything (usually don't even get to try anything for like 3 minutes), so I didn't want to risk plugging it in without a transformer if it's a voltage problem.

Update: I got it to something playable, so leaving this here in case anyone experiences anything similar with theirs: I left it on for a while and I was noticing that the screen was going really dark/black when the game was on a stage with a dark background. Then it happened to get to a stage with a lighter background and the screen started getting insanely bright/washed out. I did have to turn the flyback screen pot down to alleviate this a bit, it's still exhibiting this behavior slightly though.

I managed to play around with the pots on the remote board and flyback and calibrate with the brightness and R, G, B gains (mostly turning the green down) enough to get about 80 to 85% brightness and quality I'd say. It was very much playable for at least an hour, but I'm not sure if I can get it any brighter or sharper. The remote board unfortunately seems limited and doesn't have contrast and only 3 out of the 6 R,G,B settings.
I unplugged everything and will check it again when I get home for consistency, but at least I know I can actually calibrate it to something playable.
Post Reply