Isolated Transformer / Monitor fuse blown

[friedpotatoz]

Hello all!,

I will try to make this short but I have been trying to fix this issue for a while now. I bought a KI2 cab that keeps blowing its fuse on the chassis. I have been learning through out this whole process but still haven’t gotten it to work.

Long story:

Bought the cab, I saw that the fuse on the chassis was blown so I replaced it. Every time I turn it on it blows the fuse, I have gone through so many trying different things. Turns out the previous owner just gave up, he did tell me he swapped the original monitor and chassis because it wasn’t working anymore. I didn’t know that older monitors need an isolated transformer so I looked into that.

The previous owner had an extra cab so he told me I could grab the monitor plus all the wiring and chassis. I thought the chassis was bad so I just installed that 2nd monitor and chassis and fired it up and again its fuse would blow. So now I have 2 monitors and 2 chassis that do the same thing. At first I thought it was the power supply so I bought an exact replica from eBay but still nothing changed. Learning of the iso transformer I saw that he had one from the 2nd cab when I grabbed all the wiring.

Now back to the isolated transformer, I had to buy another EMI filter because the original one was shot. I looked online to see how everything works and needed to be connected but I always saw these transformers connected to the HAPP like power supplies (longer ones), the one in my cab is the peter chou one. (Not sure if that makes a difference)

This is how i have it so far:

Overall
https://flic.kr/p/PmXYm7

Power Cord spliced to EMI Filter
https://flic.kr/p/NRGYAU

EMI to Transformer
https://flic.kr/p/NbTgRT

Transformer to wires that connect to power supply and fuse, white/red and yellow/black wires
https://flic.kr/p/Pf6vPk

Chassis (Doesn't have any naming on it, not sure what type it is)
https://flic.kr/p/Pf6vQx

Fuses used
https://flic.kr/p/Pcx5Go

Not sure what else to do, everything else seems to work I can even hear the game. Lights work fine plus the small fan for the pcb turns on fine. Could something else not be grounded?

any help would be appreciated.

Thanks
John V.

 

[Mitsurugi-w]

If you hooked that monitor up without an ISO then you most likely now have another problem on the chassis other than the fuse.

It looks like a K7000 btw.

 

[friedpotatoz]

If you hooked that monitor up without an ISO then you most likely now have another problem on the chassis other than the fuse.

It looks like a K7000 btw.

Thanks Mitsu,

Yes I did before knowing I needed a ISO. I got some info on Klov on the potential steps I need to take to fix this thing. Also read that these K7000 chassis are a good for learning as they are a bit easy to work on.

So what was suggested to fix and replace is:
horizontal output
flyback
voltage regulator
shorted bridge rectifier diodes
shorted poly caps (big fat caps behind the flyback)

I am very new to fixing/replacing monitor parts so security0001 is helping me out.

I just want to make sure I have the iso connected correctly. So when I do replace and fix this chassis I don't blow up stuff again lol.

 

[friedpotatoz]

Ok so I replaced a few components on my K7000 chassis and now it works, here is what I replaced just for future reference. I blew out some parts by not having an EMI filter and isolated transformer in my cab. Hopefully this will help.

Flyback:
https://www.arcadepartsandrepair.com...eries-flyback/
Diodes: D19-D24 use a 1N4007 diode
https://www.arcadepartsandrepair.com...piece-package/
Hot:
https://www.arcadepartsandrepair.com...itors/2sd1398/
Voltage Regulators: These may vary so just look at the number/letters on the one you are replacing.
https://www.arcadepartsandrepair.com/store/monitors/str30130/

Working Killer 2 Dedicated Cab:
https://www.instagram.com/p/BOJDgGLgWXi/?taken-by=friedpotatoz

 

[twistedsymphony]

k7000 are one of my favorite 15KHz monitors. the picture on those is damn near perfect with a well looked after chassis.

even with all the issues you've had it's probably for the best.
I have a dedicated KI2 with the original chassis (WG U2000) and while it doesn't require an ISO the chassis is a giant turd, they're prone to failure and even when freshly rebuilt they don't look all that great (washed out and seemingly impossible to get the convergence perfect). My MK3 has a K7000 and it blows away the picture on KI2.

 

[friedpotatoz]

k7000 are one of my favorite 15KHz monitors. the picture on those is damn near perfect with a well looked after chassis.

even with all the issues you've had it's probably for the best.
I have a dedicated KI2 with the original chassis (WG U2000) and while it doesn't require an ISO the chassis is a giant turd, they're prone to failure and even when freshly rebuilt they don't look all that great (washed out and seemingly impossible to get the convergence perfect). My MK3 has a K7000 and it blows away the picture on KI2.

True, I'm glad I had all these issues, was a good learning experience. Before this I had never messed with arcade monitors but I think it was way overdue with now having 10 cabs :/

Picture is very nice, I do agree on that. I think I have to do a cap kit, I am getting a squished portion on the bottom on the monitor. Been told a capkit could fix this, I mean its all original I'm sure these caps are slowly dying off.

Heres what I mean: Mortal Kombat 1

 

[twistedsymphony]

yup, "fold over" along one of the edges is a classic sign of failing caps. cap kits on these is pretty straight forward I've done a few of them EDIT: looking at the video again that's not exactly fold-over, more of a linearity issue, still could be fixed with fresh caps.