PLEASE HELP: Punch-Out dual screen, top screen has only small line in middle

[davez]

well..

well maby i will wait to desolider them, there is a home based electronic's store in my area he fixes tv's and all other kinds of electronics so im going to call him in the morn and see if he has any of them.....

 

[davez]

update

ok guys, again THANK YOU ALL for all the good responces and help!!!

here is a update, i just got back from my electronic's guy and he only had one of the transistors, but thats fine.

also he told me that if the transistors do not fix the problem it could also be a CAP he told me to look around the spot where TR402 and TR403 are for a 100uf cap and replace them if the transistors do not fix the vertical line.

also he has a older wrestling arcade machine thats fully working, i forgot the name of it but its something like M**** Wrestling or something like that. But he is going to sell me it for $100 !!!! So im glad that I stoped in!!

im going to now put in the new transistor and one of the old ones back in and see what happens. i will post what my results are

also incase anyone wants to know here are the replacment values for the transistors

TR402 = C2073 = NPN 375
TR403 = A940 = PNP 398

 

[davez]

still broke!

well guys, here is the update, i put the NEW transistor into spot TR402 = C2073 = NPN 375.. put it all back together and turned on the machine....

STILL SAME PROBLEM.. white vertical line....

so i decided to take the sound board out and use the TR403 = A940 = PNP 398 to put in the video board... so i did that and put the bad one from the vid into the sound... powerd it up and.....

STILL SAME PROBLEM.. white vertical line... and the sound still works...

So now I know that this problem has NOTHING to do with TR403 & TR402

So now what do I do??? Im going to try to replace the 100uf thats close to the TR403/402

Does anyone have any other ideas????
I relly want to get this fixed!

PLEASE HELP
Thanks

 

[MundoMan4]

I know this is probably stupid to ask since you said you "tryed tweeking the video switches on the screen" but have you tried adjusting the V-Hold and V-Size ???

I had a Gorf that had everything repeated on the screen and was sure it was a PCB issue, until someone suggested vertical hold. I didn't think it would do anything but somehow the messed up hold had the image repeating perfectly, instead of rolling like a TV

 

[davez]

yah

yah everytime i did anything to it then i put it back in the cab.. i adjusted every switch, just to see if something would happen... but nothing fixed it.

thanks for the reply

im thinking that maby replacing the CAPS will fix it, like what my buddie said that ownes a electronic store

so tomarro im gonna buy the caps i need from him..

unless someone here can figure out something diffrent i can do to fix this

 

[modessitt]

Sometimes vertical collapse can be caused by recapping the monitor.

Another thing to check would be the vertical yoke. Make sure the connector (green and yellow wires) is on properly first. if it is, then unplug it and do an ohm measurement between them and make sure you get a reading above zero and under 100 ohms...

 

[davez]

oh so if someone recaps it then that could happen.. well this has never been recapped its all orignal parts in it.. so i guess the only thing i can think of to do is to put new caps in it...

any ideas on what elce could be the problem?
thanks

 

[modessitt]

any ideas on what elce could be the problem?
thanks

Yes. It was the 2nd thing I put in my last post....

 

[davez]

where would i find the vertical yoke? on the chassie? where at? im still kinda new to this, but im very good at electronics.... thanks

 

[modessitt]

There are four colored wires going from the yoke to a connector on the chassis. thet are colored blue & red (horizontal yoke) and green and yellow (vertical yoke). Unplug the connector and measure the ohms between the yellow and green wires. You should get 50 ohms if your vertical yoke is okay. If you get a zero, then it is shorted (bad). If you get nothing, then it is bad and the reason you have a line on the screen.

if it's 50-ohms (approximately), then replace all the caps....

 

[davez]

when i test green and yellow i get 56.1ohms testing @ 200
when i test blue & red i get 02.1ohms testing @ 200

testing @ 2k for green and yellow i get .056kohms
testing @ 2k for blue & red i get .002kohms

so does everything look ok?

so when i replace the caps, do i replace ALL the caps on the chassie? or only sertain ones?

thank you so VERY much for all the help dude!!!

 

[modessitt]

Okay, yoke sounds okay. Replace all the electrolytic caps on the chassis....

 

[davez]

awsom! i kinda got scared thair for a sec... lol.. i didnt want to get a bad reading.. so then it soulds like after i replace the electrolytic caps i should be all set and the monitor should (hopfully) work...

again dude...... thank you so very much for all the help

i will buy the caps tomarro and ill post here what the outcome is after i replace them all

THANK YOU

 

[davez]

does anyone have a list of all the caps? the uf and v of each?

thanks

 

[modessitt]

You can order a deluxe cap kit from Bob Roberts. You have to mail him a check, but he ships fast and will have what you need. Send him an e-mail telling him what you need and give him your name and address and he'll respond back with a total with shipping. Look around his site to see if there is anything else you need....

 

[davez]

yah well i would do that but i cant wait. lol.... i can buy what i need from radio shack and my local electronics fix it guy.. so thats why im looking for a list of all the caps so i can buy them local
thanks tho

 

[modessitt]

Well, here's a list, but it doesn't include the ones in the power supply.

http://www.ionpool.net/arcade/capkits/Sanyo_20EZV_Zanen.txt

Still, if a cap is causing your deflection loss, then these should fix it...

 

[davez]

well here is a update...

i brought the chassie "Video PCB" to my electronics dude.. he tested all the CAPS on it.. He found 2 that were not reading at all. So we replaced them with new CAPS... Put it all back together and i still have the white line...
so here is everything i have done so far....

1) Messed with all the switches and knobs..
2) Replaced the TR402 & TR403
3) Tested the yoke.. Got reading 56
4) Replaced the 2 non-reading CAPS

and after all this that i have done....the monitor still has a vertical collapse (small white line in middle of screen)

so does anyone have any oher ideas of what i can do?
should i replace all the caps even thoe they are still ok and working?

thankxx

 

[modessitt]

I'd replace all the caps if they are old caps. Look over the entire thing for cold solder joints. Make sure the VSize pot isn't bad. Possibly replace the IC on the board. Look for cracks in the chassis around the flyback/yoke connector, as sometimes it gets little cracks from people holding it on the back right corner and the weight of the chassis makes it crack. I found one like you have that had a crack right across a trace to the yoke connector...

 

[davez]

ok where do i find the IC ? is that the big 20 sum pin chip on the board?

yah ill replace all the CAPS here tomarro...
and if that doesnt work then probally ill just resolider everything on the board... just to make shure everything has good contacts and nothing is cold...

thankxxxx