Build Your Own Arcade Controls Forum

Main => Monitor/Video Forum => Topic started by: smalltownguy on April 12, 2011, 08:38:24 pm

Title: Wells Gardner 25K7101 has red tint
Post by: smalltownguy on April 12, 2011, 08:38:24 pm

Capped (I'm told anyway...) and a new flyback.  Pictures below tell the rest of the story.

Other than the obvious degauss, where should I start? I've already played with the pots on the neckboard, and they DO change each color to a degree. but the red drive is turned all the way down and this is what I have:

(http://i45.photobucket.com/albums/f66/smalltownguy2/IMG_8947.jpg)

(http://i45.photobucket.com/albums/f66/smalltownguy2/IMG_8948.jpg)

Title: Re: Wells Gardner 25K7101 has red tint
Post by: coliveira on April 12, 2011, 10:29:13 pm

I had a similar problem that's been fixed so I was going to refer you to this link http://forum.arcadecontrols.com/index.php?topic=110056.0. (http://forum.arcadecontrols.com/index.php?topic=110056.0.)  However, you're one of the people that helped me on that thread so I'm guessing you've already checked what worked for me...  Whoops.

Good luck cuz I got nothing for ya but good wishes for a helpful guy... :dunno

Chris

Title: Re: Wells Gardner 25K7101 has red tint
Post by: smalltownguy on April 12, 2011, 10:52:27 pm

You know, I HAVEN'T checked the input header pins, actually.  :banghead:

*runs off to pull the chassis & look*

Title: Re: Wells Gardner 25K7101 has red tint
Post by: coliveira on April 12, 2011, 11:00:11 pm

Ha ha.  You'll have made my day if that's' what it is!

Good luck!

Title: Re: Wells Gardner 25K7101 has red tint
Post by: Kevin Mullins on April 13, 2011, 10:04:27 am

Cracked solder on the input header pins typically results in "missing" color, not too much of a color.

Remove the red input wire from the header, if the screen is still red, then it's a chassis or tube issue for sure.

I'd swap the red color drive transistor with another one. (blue or green)
Verify the red adjustment pots are both in spec. (drive and cutoff)
Test the tube with a crt tester/rejuvinator for color gun shorts. (run a clean cycle)

Title: Re: Wells Gardner 25K7101 has red tint
Post by: smalltownguy on April 13, 2011, 12:28:47 pm

I'll start with removing the red input pin and see what I get. (I will also double check input pins)

Next I'll swap drive transistors to see if the problem migrates.

Lastly I'll beg, borrow (or steal!) a Sencore rejuvenator from a local TV repair shop owner who's recently retired near me.

Will report back with what I find...

Title: Re: Wells Gardner 25K7101 has red tint
Post by: smalltownguy on April 13, 2011, 09:19:01 pm

I pulled the red input and fired her up again tonight, and I can still see some red tint when I turn up the screen pot. I'm beginning to think the tube has a short. I'll have to get my hands on a rejuvenator if that's the case.

Since I received this tube in a cab with no chassis, I cannot verify that the tube is/is not bad, until I hook up a known working 25" chassis to it. This weekend I'll be repairing another 25" chassis that's compatible with this tube, so I'll test it to be sure.

Title: Re: Wells Gardner 25K7101 has red tint
Post by: Kevin Mullins on April 13, 2011, 09:39:02 pm

Can you turn the green up ?

I see blue in one of those pics, but there is no signs of green.
red + green = yellow
red + green + blue = white

Title: Re: Wells Gardner 25K7101 has red tint
Post by: smalltownguy on April 13, 2011, 10:12:49 pm

Yeah, there's green. Not much, but it's there. Yellow Ms Pac tells me there's at least a little bit.

I really need to get this chassis on a known working tube and then I can see what's going on with it.