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choosing a monitor


PM1745 Sanwa
Posted: Aug-7-2015 7:00 AM
Join Date:Aug-6-2015
Post: 11

Hi Guys,

Since couple of days, i'm digging on the internet to find some answers but not much to find.
My Chassis of my arcade game Virtua Stricker 2 has blown up without any notice.
before it worked fine and now dead.

My fuse of 1.6 A blowed up. But also a resistance and some transistors that i'm not able to recognice any more,
On first sight i see:
R817 burned: no idea of the value
Q802 exploded
Q803 exploded
Q804 exploded

This is what i visualy see.
I don't have any clue how the situation is on the other components.
It seems that there was already somebody before me who tried to fix it.

How is this possible? seems those chassis has a lot of problems.
Can somebody help me?


Click on the image to zoom in

Click on the image to zoom in
Posted: Aug-9-2015 1:38 AM
Join Date:Jul-9-2012
Post: 133

That looks like a mess! I wouldn't even be able to get that to work lol! I would send that chassis in for repair, I send all my broken chassis to http://pnlvideo.com/ he fixes everything perfect and fast!


ArcadeMonitor.com helping people fix arcade monitors and great products.

Posted: Aug-10-2015 6:29 AM
Join Date:Sep-12-2011
Post: 2

stijnie,

Do you know the model number of the chassis? If not, How about a full shot of the chassis?

Posted: Aug-10-2015 11:57 AM
Join Date:Aug-6-2015
Post: 11

@Arcademonitor:
Thanks for the reply, 1 small issue, i'm living in Belgium.


@ Spunkmeiser

It is a PM1745c serial 67A070.
attached some shots.



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Click on the image to zoom in
Posted: Aug-10-2015 2:13 PM
Join Date:Sep-12-2011
Post: 2

stijnie

R817 ~ 1/4 watt 1.5k fusible. If you don't have a fusible, use flameproof.

Q802 ~ 2SA1091

Q803,804 ~ 2SC2482

Check Q801, might be bad. Check D801 (bridge rectifier) Also, check all the low value resistor (under 100 ohms) I'm not sure of the line voltage there, but from what I see in the schematic this chassis is 120v ac 50/60 HZ. If any of the parts test bad, or if you're not sure- replace them.

Hope this helps. Let me know if you need anything else.

Posted: Aug-11-2015 1:16 PM
Join Date:Aug-6-2015
Post: 11

Hi Spunkmeiser,

Indeed my monitor runs on 110VAC

I started this evening to inspect some parts.
So what i have found is a lot of parts who are not good anymore.
here is the list of potential bad stuff i assume.

C801 : TSL 1110 Inductor: 0.1 ohm = shorted?!
C808: 2Mohm : normal?
C812: 12kohm: not normal; partly shorted
C806: 2Kohm: partly shorted
C312:10.7Mohm: normal?
D801: ok
D802: ok
D803: oK
D805: 0.4V and goes up while measuring : will replace by new one.
Q801: Shorted
R804: 14K
R817: fried like chicken
R819: 82-84 ohm fluctuation : repalce
R806: 67.6 ohm
R816: 76ohm
R442: 0.3ohm: shorted?
R455 : 0.4ohm : shorted?
R816: 74ohm
R811: 26ohm
R312: 4ohm.3

About the Resistors, i need to check with color code.

Do you have some doubts of electrolytes who might be broken that i didn't check?
Isn't it the best to do a capkit as well?

What i saw of my hot, there was a blue cover on it , but the HOT had no heat paste between HOT and alu frame.





Click on the image to zoom in

Click on the image to zoom in
Posted: Aug-12-2015 3:34 PM
Join Date:Jul-9-2012
Post: 133

That sucks you're so far away! That looks like a really challenging repair. Maybe you can ask a local arcade or route operator who they send their boards too? If you start buying all those parts you can easily go up and over the price to repair it and still not have it working.


ArcadeMonitor.com helping people fix arcade monitors and great products.

Posted: Aug-17-2015 10:39 AM
Join Date:Aug-6-2015
Post: 11

Hi Spunkmeiser,

I'm approaching the final stage of dissambling my chassis :-)
what have i seen:
I have found that my transistor C5143 (horizontal deflection) is shorted as well.
Q805 CBF421 also shorted.
Most resistors below 100 ohm seems to be ok. Value is the same as color code, is this necessary to chance those who seems ok as well?

I have some doubts with some resistors. can you give me the vaulues of:

R806:
R442:
R460:
R819:

What can cause such a massive destruction?
electrolyts only?????

If i'm ready with everything, i will post all the components i have investigated by type and chassis number, so other people can use it in the future for easy ordering parts.

Stijnie

Posted: Jan-1-2016 12:57 PM
Join Date:Aug-6-2015
Post: 11

Hi everybody
So i finally have found and also bought a 2nd hand chassis out of UK.
I kept it as guideline.When i thoughts that i will repair my broken chassis and it might blow up again then i can check with my good chassis.

So i replaced a lot of things.
All Elco's , i have found 1 who was not good. by measuring with a capacitor instrument.

next transistors were blown or shorted:
D404: C5143
Q403: C4544
Q801:C3831
Q805+Q802:BF421
Q804+ Q803:C2482

I replaced blown up resistors:
R819: 3.9Ohm
R817: 1.5Kohm

I replaced Q 301 and Q 302. When i was measuring the individual diodes , the volatage moved down or up.

I checked all resistors,
I have checked all diodes and rest of transistores, all fix voltage between 0.4 - 0.7 V
All seems ok by me.

I have also measured the windings on the CRT and seems also ok.
SANWA
Sanwa pm1745 29"
Rh-0.9ohm
Lh-0.405mh
Rv-8.5ohm
Lv-18mh Is

Proud as i was i have put it in and turned on the power.
Nothing happend exept a loud zooming noise who comes out of my CRT.
noting to see on the CRT, no light in the Yoke , nothing.
I have shut immediately the power.
I took the second hand Chassis but same problem occured. I have measured the power voltage and i have 103.7 VAC (50HZ). with Chassis connection and without. So power supply seems to work...
all the rest works fine. ( computer , sound lights etc...)


Who can help me out?



HELP!

Posted: Jan-3-2016 7:20 AM
Join Date:Aug-6-2015
Post: 11

Hi everyone ,
So i have done yesterday some try outs.

That zooming or electrical zooming was not coming from my CRT but was coming out of my boxes.

So i started up everything without my video signal( connection on sega computer) and after few seconds i saw my bulb lightens up.
good , i see horizontal lines and grey color screen.

when i restored the video connection, i see and hear a electrical spark while connecting the white wire (n°5 on the connector).
it mean that there is a lot of amp. that goes trough that.
when this happens my sound out of my boxes start to zoom again.
i directly undo the connection.

After that , i took off the print from my bulb and it stays the same. like above

I took out my segacomputer and desambled.
i looked on the video board , but nothing to see on that, only IC's ans diodes.



Video board is broken and because of that everything was ruined?

What now?

Posted: Jan-4-2016 12:31 PM
Join Date:Aug-6-2015
Post: 11

What have i learned today:

After al lot of effort i found out that i have a potential difference on the groundings between chassis and common ground on the transformer.
After trying and trying and blowing up my 2nd chassis, i found that i connected the small black ( grounding) wire from the back of the CRT to my chassis in stead of on my bulb PCB.
I put the black grounding wire on the Bulb PCB, potential difference gone , screen starts up, no zooming noise.
Excellent!!!!!!!!!!!!!!


Only next problem.
My screen turned into yellow and caqn't see a thing.
Only when i put my connector on low resulution , i can see some things and i see my screen double.

first fixing 2nd chassis again of and hopefully i have good chassis and a good screen.

to be continued.

Posted: Jan-5-2016 1:06 PM
Join Date:Aug-6-2015
Post: 11

Hi everyone,

So i repaired my second chassis.
all the same things were blown as my first one.
Luckily i bought multiple components from each type.
So in no time it was fixed.

I put in my chassis, turned everything on.
i have only blue screen and see my game
But just partly.
the static screen i can see, dynamic ( foodball players) i can't see.
see video posted on you tube:
https://youtu.be/50LDJBesibQ

On the screen you see flashes of triangles etc...


I pulled off my video connector.
stable screen ( grey) with horionzal lines.
When i adjust color, i can see all colors: red, green, blue.

When putting in the video signal from my sega computer, only blue color.
Seems my sega is sending out only blue color.
dynamic images , he can't send out, only flashing things.

I'm pretty sure that the last step will be changing video board.
I'm out of experience.

Can somebody help me out?

Posted: Jan-9-2016 12:46 PM
Join Date:Aug-6-2015
Post: 11

Hi Guys.

I have taken my old Sega master system ( 8 bit). Opened the cover and took the RGB + ground + sync signal. i wired this directly to the monitor. I placed the connector on low resolution.

I still have a problem with red color.
I can adjust only red color on chassis , not on the external potentiometers.

I put my second chassis in and red color is ok, i have a nice screen with alex kid in miracle world :-)

Ok, last but not least.

1. I have a Video board that is broken. I try to serach for a other one. it is a Model3 step 2
Seems they are very expensive and hard to get.

2. I have a hybrid RGB module that is also partly broken. Where can i find this module? I can't find this on the internet! it is a Xinwa BX6341

Posted: Jan-9-2016 9:18 PM
Join Date:Jul-9-2012
Post: 133

You're doing it all wrong Alex Kidd hooks up to a TV lol


Click on the image to zoom in

Click on the image to zoom in

ArcadeMonitor.com helping people fix arcade monitors and great products.

Posted: Jan-10-2016 1:06 PM
Join Date:Aug-6-2015
Post: 11

HAHahaha,

Yes indeed, but i don't have any output who generate 24KHZ or 15Khz.
But my old sega does :-)
I wanted to know if my repairs on the chassis were succesfull.


Still no module found, somebody who might help me?

Posted: Jan-11-2016 11:58 AM
Join Date:Aug-6-2015
Post: 11

Hi, My red color is solved, seems that i turned soo much on the potentiometers on the chassis.
Now everything works fine on 15KHZ. I can't try on 31KHZ. Original Sega video board still broken.

In meantime RGB module found on Aliexpress.com. but no need to order anymore.

I hope nobody will have this issue like i have been trough; or at last the solution is written above here.
it took me almost 1/2 year. But it was fun.

So last thing Video board Model 3 step 2 repair.
Any recommandations where is can find some information or IC's?

Thanks for the help Arcademonitor and Spunkmeiser.

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