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Main => Monitor/Video Forum => Topic started by: Meat Popsicle on August 28, 2007, 01:19:24 am

Title: WG 25K7193 Color problems, white is yellowish
Post by: Meat Popsicle on August 28, 2007, 01:19:24 am

Hi Guys,

First off its a WG 25K7193.

So I had a monitor from another project that I recently harvested.  I hooked it up for the first time and noticed the colors were off.  Specifically that the whites were yellow, the reds bled a bit and the overall image was a bit too greenish.  Adjusting the gain and drive pots did not yield the results I wanted.  So I went ahead with a cap kit.  Hooked back up, the red bleeding was gone but I was still left with the yellowed whites and a slight green tinge.  I adjusted all sorts of combinations of the RGB gain/drive nobs with no luck.  The only thing I did not adjust was the focus and screen on the flyback itself.  (they could have been bumped or mal adjusted in the past but not by me).

I thought maybe one of the transistors was bad so I tried to swap the blue with the green transistor to see if either was the culprit.  But I still have the same results and need some advice of where to look next.

Thanks in advance

Some reference images:
red.jpg = gain and drive pots for that color at 100 with the other two pots at 0
green.jpg = gain and drive pots for that color at 100 with the other two pots at 0
blue.jpg = gain and drive pots for that color at 100 with the other two pots at 0

hue .. the text should have a blue white color to it .. I can put a good reference image if needed.

Title: Re: WG 25K7193 Color problems, white is yellowish
Post by: Ken Layton on August 28, 2007, 02:04:25 am

If the tube is a Zenith then it needs to be either rejuvenated or replaced with a new one.

Title: Re: WG 25K7193 Color problems, white is yellowish
Post by: JoeB on August 28, 2007, 03:14:18 pm

how does one get a new "tube" ??   :)

I got a 25K7193, and the picture is not as bright as I'd like to.  If I push the brightness, the blue's start bleeding.

Title: Re: WG 25K7193 Color problems, white is yellowish
Post by: Meat Popsicle on August 31, 2007, 01:46:55 pm

If there was a sticker indicating the brand at some point it has long since fallen off.  The only remaining identifying stickers are some 'Laniel sticker' on the neck, 'PIX Tube ser NO. WG332392' and 'May 6th 89, 3rd shift 2827'  I can't say for certain but I don't think it is a Zenith tube.

It has been suggested to me from another source that the problem could be a convergence issue.  Would anybody have  a link to a convergence F.A.Q.  Or any other suggestions?

thanks

Title: Re: WG 25K7193 Color problems, white is yellowish
Post by: grantspain on August 31, 2007, 02:18:14 pm

that ain't no convergence problem,its either bad adjustment,leaky transistors or caps or most likely like ken said a dying tube

Title: Re: WG 25K7193 Color problems, white is yellowish
Post by: Meat Popsicle on August 31, 2007, 02:52:41 pm

Quote from: grantspain on August 31, 2007, 02:18:14 pm

that ain't no convergence problem

Well that's good to know as I really didn't want to mess with that anyway.  I'll start looking in my area for someone with a rejuvenator.  What would one consider a fair rate for zaping a tube?