Anyone know what monitor this is? EDIT: Didn't think so :)

[OldSchool79]

I own a 20" lowboy cabinet which I've fitted with an IPAC. It has a monitor that I wired the PC into and I can display pictures fine but it has a slight vertical fold over at the top.

I need to work out what sort of monitor it is first before I can fix it, so here's the images:


The vertical fold over in action. It is quite nastier in the higher resolutions, this is 320 x 240.


Here is the back showing the video connector. I jerry-rigged my own VGA cable into it...


Side view showing the adjustment pots. Most of these are on another little board connected by wires about 0.8 metre long.


Sticker on one of the heatsinks.


Possibly a model number on the circuit board.


Sticker on the tube.


Top view.

It's something similar to the Sanwa shown on the sites mentioned in this forum's monitor FAQ, but not quite. Anyone know?

EDIT: I should also mention that I saw this vertical fold over with a Capcom game plugged into it, I just didn't realise it at the time it was my first arcade monitor I've bought so I don't think the fold over is related to my cable hack.

[hiperco]

Probably a stupid question...but did you try tweaking the settings in the config program?  (SHIFT "J", for example, I would think, from the screen shot).

[Ken Layton]

Sanwa monitors are extremely rare in the USA. I've fixed monitors for 30 years and have never seen a Sanwa.

[OldSchool79]

hiperco:

Yes I've tweaked for days. At first I thought I had a dodgy cable setup and/or my video card couldn't display the image properly, but then I remember when I was buying it, at the guys shed, he plugged in a CAPCOM game and I saw the title screen which was mostly black, hence why I didn't see the fold, but when he unplugged the video (but still had power going to it), it had a bright grey screen and there was a fold over at the top showing bright white. When I unplug it at home it does the same thing. I can get an unfolded screen in the lower resolutions (256 x 224 for eg) but there has to be about a 2 inch black border. As soon as I try to get it to go any larger it folds over.

Ken:

Ah I see why everyone had blank looks when I asked around. Replacing the harness with a new universal one will be my last resort, but I'd like to try and fix it by replacing components first.

[Thenasty]

I had a problem like that with my WG 46xxx or was it 49xx series..anyway, a CAP KIT did the trick.

[OldSchool79]

Which capacitors in particular do you have to check? What values are they?

And another question, in the photos there's a black wire ring around the screen, is that a degaussing ring? It doesn't seem to be working if it is, because I have a purple patch on the right hand side that has been there ever since I moved it in my car. Is there something that has to be done to activate it?

[pcb]

Best bet is to just find every electrolytic cap, and replace them all.

Yes, that black thing around the tube is the degausing coil.

[OldSchool79]

Yeah I think I'll replace them all.

If it's a degaussing coil it doesn't work!! Or I just dont know how to make it work!

[Karetaker]

You don't have to do anthing to make the degaussing coil work. It does it's job when the monitor is first fired up, then shuts off so to speak. Even with a degaussing coil wrapped around the monitor, you may still need to degauss manually from time to time.

[OldSchool79]

Yeah I'm going to invest in some degaussing equipment.

[Jomac]

Sorry it took so long for me to respond to this ,

You did ID this Chassis Correctly as a Sanwa PM-1723 Rev E

Most common fault Vertical Fold , you need to replace C319 (10uf 50v) and C322 ( 4.7 160V )

While you are there , these things run very hot and nearly always have bad solder joints so while it's out have a good look over it.

Jomac

[nwhutt]

I had one of these in my Space Harrier mini sitdown, had the exact same fault, recapped it and it was perfect after that.  It had a really good picture afterwards, far superior to the temporary Hantarex MTC 9000 I have in my Space Harrier Sim at the moment. 

[OldSchool79]

Crikey Jomac thanks for the tip, this could save me HUNDREDS of hours as I tend to do things slowly and with a cup of coffee every couple of hours. Also yes Jomac I did notice a few cracked solder joints especially on the high wattage resistors and I resoldered them, the PCB is quite burnt looking in places, maybe a fan wouldn't go astray when I install it in the cabinet again. Do you know the power consumption of them?

Also nwhutt, yes I agree, it seems to be a very high quality picture, compared to what I've seen and heard of other makes. The geometry is perfect as far as I can see (apart from the lovely fold over).

I'm going to order these caps now. I'll keep you posted!

EDIT: Uhh. I can't find 4.7uF 160v for sale anywhere... int'resting.

[Ken Layton]

Mouser Electronics (www.mouser.com) has these capacitors:

#140-XRL160V4.7 Xicon brand 4.7 uf @ 160v (9 cents each)

#140-HTRL160V4.7 Xicon brand4.7 uf @ 160v (11 cents each)

#75-515D160V4.7 Vishay brand 4.7 uf @ 160v (32 cents each)

#647-UVZ2C4R7MEH Nichicon brand 4.7 @ 160 (50 cents ea)

#647-UVR2C4R7MEA Nichicon brand 4.7 @ 160 (39 cents ea)

Jameco Electronics (www.jameco.com):

#330595CH 4.7 uf @ 250 volts (11 cents each)

#330851CH 4.7 uf @ 250 volts (14 cents each)

[OldSchool79]

Thanks Ken!

EDIT: Aw crikey! Shipping costs to the land down under are a bit steep! I might keep looking for an Australian supplier.

EDIT2: I notice mouser.com has 'high temp' electrolytic caps. Do you think putting in one of these would reduce the likelihood of this failing again?

EDIT3: I just had a look at those capacitors, and they were what I suspected, since they are fairly small, fairly high voltage, and are nestled in between a large resistor and a power transistor heatsink... hot hot HOTT

[DarkKobold]

This is a great place to post a great read!

http://groups-beta.google.com/group/rec.games.video.arcade.collecting/messages/74074b3cf981b6db,534938bf6c1b4f17,199807cd09337814,0a959bf2aa01117c,6593deb3ac027d5f,2b66833896e6aa7f,2a2835003e97cfe7?hl=en&thread_id=b7936297d58a7316&mode=thread&noheader=1&q=temp*&_done=%2Fgroup%2Frec.games.video.arcade.collecting%2Fbrowse_frm%2Fthread%2Fb7936297d58a7316%2F199807cd09337814%3Fq%3Dtemp*%26rnum%3D2%26hl%3Den%26#doc_534938bf6c1b4f17

[OldSchool79]

This problem has been resolved.  Thanks Jomac for the info, you were spot on.

I noticed the old ones had 105 deg C written on the side, and the new ones had 85 deg C on the side. I wonder if this means they wont last as long ? Yes maybe I should ask it in the previous mentioned forum...