WG 25K7184(Zenith) to dim

mrsodapop

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HI All,
I got a WG25K7184 (Zenith model) that seems to have a nice pic.(from what I can see), but is very dim. I thought a cap kit would help, but has not helped. Flyback and brightness adjusters seem to work, but cannot get it bright enough for proper viewing. My B+ is 108vdc on one side of resistor, and 164vdc on the other side. I do not have a manual, but these voltages seem off to me. Any ideas??
Thanks for any ideas
Aaron
 
I got a WG25K7184 (Zenith model)

If you positively identified it as a "WG25K7184"....then it is not a "Zenith model".
Might have a Zenith tube, but that's a difference story.

My B+ is 108vdc on one side of resistor, and 164vdc on the other side.

That is definitely odd.
Check the resistance of that resistor. Make sure your meter battery is good. Use the heatsink it's mounted to as ground.

Most likely it is that the tube needs rejuvinated.
 
The voltage regulator may be wrong, or failing. You should have 130vdc and this low voltage can cause it to be too dim, though it will usually have a smaller picture as well.
 
I went and checked the resistance of resistor, it Ohmed out at 177(yep, 9v battery in meter is fresh), and is stamped on the side at 180 ohms. I think I'll order a new VR and see where it goes from there, unless someone has another idea?? Also posting a pic to show that it is a piece of s@%t Zenith, however went by the tag on the frame that said 25K7184 for model #.
Thanks for your info.
Aaron
 

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That is a Zenith. You should check other components in the VR circuit before assuming it failed. Check out resistors 84, 85, 86, and 102...
 
Also posting a pic to show that it is a piece of s@%t Zenith, however went by the tag on the frame that said 25K7184 for model #.

Yep, you're right... that's a Zenith made chassis.
I thought those were only used on 19" tubes. (?) Had thought production of those quit before 25" monitors became common. Could be wrong though. I have a few laying around, but have never bothered to test them.
 
Yep, you're right... that's a Zenith made chassis.
I thought those were only used on 19" tubes. (?) Had thought production of those quit before 25" monitors became common. Could be wrong though. I have a few laying around, but have never bothered to test them.


I have 19" and 25" Zenith chassis sitting on my parts pile. Honestly, I never bother troubleshooting these I just scavenge parts off of them when needed...
 
Hehe.... looks like someone has done some mixin' and matchin'.
 

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You guys think I may have the wrong chassis/ tube situation? I recently picked up this game, and this problem was there when I got it.
I did check for bad solder joints, but will go back and check the previous mentioned resistors
Thanks
Aaron
 
The Zenith K7000A and WG K7000 chassis versions work with the same tube, so no mismatch there. I have seen Zenith chassis with WG model markings before, so don't be confused by that.

Now, if you have capped it, reflowed it, and still have a dim pic, then try a rejuv. If that doesn't work, find another K7000(A) tube to try it on. If it looks better, track down a new tube. If not, you may need to get one of the guys to pull a flyback off of the parts chassis for you. It's possible your low B+ is due to a bad solder trace somewhere, or even a faulty VR, and could eb the cause of the dim pic...
 
Thanks for the reply, I'll see if my rejuvenator fits this tube, and I may replace the VR just to rule it out.
Will update with results.
Aaron
 
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