Hitachi C50 Rear Projection Television

rikitheshadow

Active member

Donor 2011
Joined
Mar 19, 2011
Messages
793
Reaction score
36
Going to open this question here knowing that it should receive a quicker response.

I have a 50" Rear Projection Television in my SNK Neo 50 cabinet, and it has a convergence issue. It is a Hitachi C50, or it is marked as C50-15SN, which I'm fairly certain now that I've determined that "15SN" means the 15Khz refresh rate that Standard Resolution games use (CGA). Right now I'm trying to search for a way to fix this issue for the cheapest way possible, otherwise I'd just replace the screen entirely.

I've searched google up and down for anything matching C50-15SN and have turned up nothing besides some people making repairs on regular C50s. In fact I found a site that sells kits, "TVrepairKits" if I'm correct. They sell convergence chips with guides on how to install them and also sell Coolant Replacement for the tubes. Right now the confusing portion is that I believe these are mostly for the at-home TV models and not this specially modified arcade cabinet screen. They do sell kits for the C50s, but there are 3 different types 2000/5000/8000, which do not seem to match mine anywhere (Model # wise). I've sent them an email requesting assistance with this, but you know I consider probably getting a better answer from the folks here who deal with this stuff everday....i suppose.

Could anyone assist me? I do not see a way I can adjust this convergence issue manually like you would a typical CRT monitor.
 
I have a 50" Top Skater and to adjust the convergence I use a remote for the monitor. Do you have the remote? I am sure that is the only way to adjust it.
 
Last edited:
I highly, highly doubt they made special projection CRTs just for arcade monitors, so any part that fits to the tubes for a normal TV should work for your arcade monitor. Even on the chassis board, I'd expect the arcade models to have a lot in common with their home counterparts. They might even share the flyback, HOT and other HV circuitry -- remember, NTSC video is 15.7kHz / 59Hz interlaced.

The convergence chips are very large black ICs with lots and lots of legs along one side. They should be mounted on heatsinks on your chassis board. Just google the part number printed on them -- they're not programmable or anything goofy, any STK3110 will replace any STK3110.
 
Last edited:
You can use the remote to adjust the convergence or
control panel and if hitachi it should have a Magic Focus Button
on the control panel. You can press it and see if it adjust itself
if the same replace both the Ics and ohm the standup resistors
Take a picture of the chassis and note the convergence Ics #
on the ic. Look over the reisistors next to the Ic anyone of them could also open up.
The ICs will be connected to large heatsinks.
From what i have seen the rear projections are the same as used in Homes
except it has less parts like tuners ant switching. but the basics are the same.
Good Luck!
 
Ok heres a look at the cabinet. I've got a story to tell so stay glued to this posts and the ones to follow.

This is the label and Model # Sticker
DSC00082.jpg


This one has a Converter Sitting over here on the Side (I think..)
Converts the CGA Resolution over to something usable to the TV
DSC00086.jpg



This is a picture of the issues I have with the convergence.
DSC00079.jpg


On the day I first tested it I only had grabbed one game to test it. I grabbed Raiden, which is a vertical top shooter. Apparently this screen does not like anything vertical, it HAS to be Horizontal.

DSC00094.jpg


Even after the game is unplugged the convergence will stay screwy when you pull up the built in test screen that can be activated on the front control panel.

BUT!

If you plug in a Horizontal game the convergence will straighten out on its own. On the second night of testing I finally brought something I could test besides my Raiden Board, Street Fighter 2 : The World Warrior. Seriously thing has a mind of it's own.....don't know why but I won't complain if the picture stays like this without any issue on horizontal games.

DSC00128.jpg
 
Funny thing, looking through this whole thing for the convergence chips. I've seen what generally the Sanyo ones used in home versions of the C50 and yet there are none like that in here. However there are some convergence resistors located on this board connecting to what seems like a large number of chips connected to the largest heat sync in this whole television. They could be the convergence chips in this unit, but I'm unsure. I guarantee you there is nothing in here like those Sanyo chips.

Convergence.jpg


There are an equal number of these on the opposite side of the large heat sync. All with a number of those special convergence resistors.





So otherwise I have no problems at the moment with this monitor. It's attitude is just determined by the game plugged into it. On a side note, people talk about having a remote to adjust certain properties in the screen's convergence.......I have no remote, but have located an Infrared receiver on the board behind the screen control interface...........but I wouldn't know where to purchase a remote that would work with this older custom C50 Hitachi.
 
I bought the remote for top skater from Betson West. Its possible they might have the Hitachi one too. I paid $50 for it. Top skater uses a Toshiba monitor and the remote is a special remote their is no channel changing or numbers its just used to adjust the monitor. I will take a picture of it later and post it on here so you can see it.

That picture does look good and it will be awesome when you get the Neo-Geo in there. I sold I thought a broken KOF2003 on eBay for $1. The guy wrote back and was like it works! Teach me not to clean the game cartridge off!
 
Last edited:
Top Skater also came with the Hitachi. I would know -- we have one. I was able to get the ICs replaced on it, but was never able to adjust out the convergence all the way like I wanted. what wound up happening was the whole RPTV would shut off, so I just cast it into storage.

I didn't bother fucking with it further cause the blue tube was going bad on it. I don't know what to do with it otherwise.

also, these run medium resolution as well.
 
I had a Toshiba on my Waverunner, and was able to use a Toshiba TV remote. My TV remote had a similar layout, with volume and channel up/down on the right, and the numbers on the left. I just looked at a picture of that remote to figure out which buttons corresponded to which functions.

DogP
 
+1 i have a toshiba in my star wars and was able to use mytoshibe tube tv remote. None of the buttons make sense heh but i was able to figure out what did what and get it converged pretty well.
 
Funny thing, looking through this whole thing for the convergence chips. I've seen what generally the Sanyo ones used in home versions of the C50 and yet there are none like that in here. However there are some convergence resistors located on this board connecting to what seems like a large number of chips connected to the largest heat sync in this whole television. They could be the convergence chips in this unit, but I'm unsure. I guarantee you there is nothing in here like those Sanyo chips.

Convergence.jpg


There are an equal number of these on the opposite side of the large heat sync. All with a number of those special convergence resistors.





So otherwise I have no problems at the moment with this monitor. It's attitude is just determined by the game plugged into it. On a side note, people talk about having a remote to adjust certain properties in the screen's convergence.......I have no remote, but have located an Infrared receiver on the board behind the screen control interface...........but I wouldn't know where to purchase a remote that would work with this older custom C50 Hitachi.

Apparently this chassis doesn't use STK's
its using discrete Transistors for the convergence amps.

Did you find the remote check with Betson or Bradys etc.
You should beable to adjust it, with the remote.
If you going to keep the monitor you should have the service remote!
You really need to try adjusting first before replacing any parts
unless you see some burned up resistors.
Adjust and then save,you may have to readjust it again
if you keep changing the game board.
Each game may have a different phase and need to rewrite to eeprom for
the 255 point convergence settings..
Good Luck!
 
Apparently this chassis doesn't use STK's
its using discrete Transistors for the convergence amps.

Did you find the remote check with Betson or Bradys etc.
You should beable to adjust it, with the remote.
If you going to keep the monitor you should have the service remote!
You really need to try adjusting first before replacing any parts
unless you see some burned up resistors.
Adjust and then save,you may have to readjust it again
if you keep changing the game board.
Each game may have a different phase and need to rewrite to eeprom for
the 255 point convergence settings..
Good Luck!

Nah, I'm not going to replace anything atm, nor buy a remote until I require it. The convergence fixed itself. It was just that it hated my vertical top shooter Raiden II, but it likes anything else horizontal. Supposedly syncs more than ya think and adjusts most of it's digital picture settings by itself (IE convergence). The remote would be handy in the future, but I don't see any point on spending $50 on something that is not broken at the moment. Maybe a later time, but I still got quiet a few parts to buy to get this whole thing back up and running.
 
Back
Top Bottom