? Wei ya chassis info ?

Long Hair

Active member
Joined
Feb 24, 2011
Messages
533
Reaction score
49
Location
Missouri
I have an empty Cabinet with only the monitor, so I order a Wei ya chassis for it.
What I need to know is does this chassis require a Isolation transformer? I was told
that it doesn't need one,but I thought it's better to ask the experts first before I toast
something. The model # is 425H. Any info will help. Thanks Long Hair.
 
I have no doc. I found it on e-bay I'll post a pic of it. On the box it said "WEISSER"
 

Attachments

  • chassis1.jpg
    chassis1.jpg
    75.3 KB · Views: 64
  • chassis2.jpg
    chassis2.jpg
    96.4 KB · Views: 64
Last edited:
I've never heard of that particular model. I can find no reference to a 425H. You might need to email Wei-ya/Huai Electronics and ask someone there.

Your picture does not show enough of the chassis to determine anything. Unless I can see the whole main board, I'd have to say you should use an isolation transformer.
 
Last edited:
From what can be seen it looks pretty damn close to the 825H model.
 

Attachments

  • Wei-Ya 825H chassis.jpg
    Wei-Ya 825H chassis.jpg
    101 KB · Views: 53
Here's some more pick's of the chassis(as good as it gets). Also what do you look for
to no if it needs an Isolation transformer or not?
 

Attachments

  • 100_1191.jpg
    100_1191.jpg
    81.7 KB · Views: 56
  • 100_1192.jpg
    100_1192.jpg
    83.1 KB · Views: 55
  • 100_1193.jpg
    100_1193.jpg
    87.4 KB · Views: 53
Definitely needs an isolation transformer.

Good thing I listened to my 5yr. old son. He told me just to wait a day or two, because I
ordered one should have it tomorrow. What is missing, that tells you it need's an iso trans.
Just want to be more informed. Here is a scan of the paper work I did receive with it.
 

Attachments

  • SCAN0022.jpg
    SCAN0022.jpg
    90.9 KB · Views: 87
  • SCAN0023.jpg
    SCAN0023.jpg
    84.7 KB · Views: 75
It does not have a "switch mode power supply" section on the main board. There would have been a transformer and a bunch of components (especially an IC) in the area of where the power cord/fuses are. That would have indicated no isolation transformer needed.

Conventional power supply sections are simple. Hence yours needs an isolation transformer. Do not attempt to connect it directly to the 120 volt line.

By the way, Wei-ya paperwork is very rare. So please upload those scans to the manuals section here for everyone's benefit.
 
It does not have a "switch mode power supply" section on the main board. There would have been a transformer and a bunch of components (especially an IC) in the area of where the power cord/fuses are. That would have indicated no isolation transformer needed.

Conventional power supply sections are simple. Hence yours needs an isolation transformer. Do not attempt to connect it directly to the 120 volt line.

By the way, Wei-ya paperwork is very rare. So please upload those scans to the manuals section here for everyone's benefit.

Will do. Thanks for the schooling on the power supply info.
 
Sync Problem

Ok. I have it all wired up, and the monitor works, so that good news to me. The bad news
is the picture won't sync up. The only game boards I have are NBA JAM, and Mortal Kombat.
I know the games have a odd sync, something like 53khz. I don't see a 50/60khz pot. So does anyone have a suggestion on what to adjust. I'll try to upload a few pics if that will help. Thanks Long Hair.
 
I messed with the Horizontal pot and now I have a picture, But now I have a few problems.
First, I believe this tube has no red anymore. Are there some things I can do before I give up on the reds. Next the pics upside down,but the words and displays are right, so do all I have to do is swap out the yellow and blue on the yoke to fix this? Thanks Long Hair
 
Vertical yoke wires are yellow and green.

Have you plugged the yoke connector into the alternate set of yoke pins on the main board? Do it with the power off. Most new universal monitor chassis like this one have two sets of yoke pins on the main board. One set gives a normal image and the other set inverts it for bouncing the image off a mirror in the cabinet (like Terminator 2).

Some gameboards have physical dip switch settings to "invert picture" (or "flip picture" ). Check your game manual for any dip switch settings that may affect the picture.
 
well I switched the yellow and green and now all is good except no red on monitor. The chassis is "new and works great", or so I was told. I still have distortion on the screen, like a bad sync.
 
Checked my setup with Mortal Kombat, and the picture sync right up. It looks good,but
still no red.I guess it's time to find a new tube to swap. Does anyone know if a 26" tube would work with a 25" chassis? Assuming the neck lines up and the yoke ohm's are
within range. The reason I ask is I seen a Zenith 26" crt t.v. for $20.00 on Craigslist. The old tube is a Zenith so I thought I would have better chance of it working. Any info will help.
Thanks Long Hair
 
Video Color or ITT

What is this? and which one do I want or need to use? If you look at post #9 a pic of the manual shows a jumper for Video color or ITT. What is this? Thanks Long Hair
 
i have done a LONG thread on the Wei-Ya chassis 429H
this chassis is very much the same..
i have schematic in the thread & more paper work for these..
"yes" you need isolation transformer..
but the problem with these chassis is they are made for Asian voltage of 100v
so your 120v will cook it..
you need change resistor R740 from 2.2 ohm to 3.3 ohm or 4.7 ohm @ 7 watt
Also R804 should be changed from 140 ohm 25w to either 160 ohm min' to 180 ohm max both @ 25 watt
 
Back
Top Bottom