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  #1  
Old 06-11-2016, 07:53 AM
Console User Console User is offline
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1991 Zenith 25 Inch Console TV

We have our 1991 Zenith Console TV yet. The Model number of this Set is SS2505TR. We had the Main Module Board replaced about 3 or 4 years ago.

We noticed that when we got it back it wasn't quite like it was before we took it the Repair Shop. It seems to have what we call Vertical Wavy Lines in the background of the Picture. It at times can make the picture shake a little. This problem is more noticed in bright screen shots versus darker screen shots.

Also, the TV takes awhile for the picture to clear up after the Set is first turned on.

Any ideas on what the issue(s) maybe would be appreciated.
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Old 06-11-2016, 01:07 PM
walterbeers walterbeers is offline
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Since this appeared after you had the board replaced, I first would suspect grounding of the aquadag, (the outer coating of the CRT), which would cause lines similar to what you describe, especially when the brightness is high. Zenith sets are known to have several ground wires that have snap on to 1/4 inch ground terminals, that usually mount to different brackets on the tuner, other boards, and the shield around the CRT. There might be a ground wire hanging loose that wasn't hooked up at the time the board was replaced. Also possibly some corona (high voltage) discharge around the CRT anode connector, or wires dressed too close to the flyback (high voltage) transformer. Take the back off and listen for any high voltage arcing or hissing, indicating high voltage discharge (corona). Make sure the ground wires are plugged in and on around the shield that goes around the picture tube. You also could try removing the suction cup, the high voltage connector that goes on the side or top of the CRT, (heavy red wire), clean it off good and snap it back on. Since the CRT holds a charge, first discharge it by sliding a grounded screwdriver under the suction cup and usually you will hear a snap (arc) to make sure that there is no charge on the CRT before you attempt to remove it. Other wise you will get a nice little shock, as you take off the suction cup, called the anode connector. Also you could have gotten a bad main board and there could be a problem in the high voltage or horizontal section causing the vertical lines. Several things on the main board could be wrong, some being bad capacitors, arcing inside of the flyback transformer, or bad connections on the board. As far as it taking a while for the picture to clear up, that could be caused by the picture tube getting weak and tired. The picture tubes in the later sets like you have, the CRTs didn't last as well as the earlier one's such as the Chromacolor tubes. Good luck with the set. Zeniths were some of the best TVs ever made.
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Old 06-11-2016, 09:23 PM
MRX37 MRX37 is offline
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Tube is probably okay, but checking for color smearing or bleeding would be a good idea.

It was around 1993 that Zenith CRT's went downhill, and by "went downhill" I mean careening downhill with a broken steering wheel and no brakes. Since yours was okay up until the repair job, the CRT is probably fine.
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Old 06-12-2016, 01:07 AM
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dishdude dishdude is offline
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Quote:
Originally Posted by MRX37 View Post
Tube is probably okay, but checking for color smearing or bleeding would be a good idea.

It was around 1993 that Zenith CRT's went downhill, and by "went downhill" I mean careening downhill with a broken steering wheel and no brakes. Since yours was okay up until the repair job, the CRT is probably fine.
Yep, '93-'95 was the bad CRT period.
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Old 06-12-2016, 06:29 PM
Console User Console User is offline
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Will turning down the G2(Screen Adjustment) help to eliminate some of this problem with the lines until I get it looked at? Is proper adjustment of the G2 with no light on the back screen of with just a little bit?

Thanks for the other advice.
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Old 06-13-2016, 07:02 AM
RCAZenith RCAZenith is offline
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Quote:
Originally Posted by dishdude View Post
Yep, '93-'95 was the bad CRT period.


I think that continued on until circa '99 or whenever they went to the RCA Thompson CRTs for a little while. My parents had a '97 BPC Zenith that had respectable picture and longetivity, even with the bad CRT, that joker lasted from the time I was in Kindergarden until I was a freshman in college with 4.5+ hours of usage a day. You would be hard pressed to find a flat screen of any description that could do that.

I have an older Zenith with a weak picture tube 1987 V3912W that is still trucking. I suspect that if I could source a brand new CRT It would last until 2087 with occasional use!


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Old 06-13-2016, 07:39 AM
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zeno zeno is offline
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Quote:
Originally Posted by Console User View Post
Will turning down the G2(Screen Adjustment) help to eliminate some of this problem with the lines until I get it looked at? Is proper adjustment of the G2 with no light on the back screen of with just a little bit?

Thanks for the other advice.
Adj in dark room with brite, contrast & color down. Should get either
dim pix or no pix and NO lines. Turn down G2 until lines just go
away.
Turn up controls to normal & be sure still no lines.

73 Zeno
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Old 06-25-2016, 05:59 PM
Console User Console User is offline
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Has anyone else ever had an issue with a TV like I described with wavy vertical lines appearing in the picture especially bright screen shots?
If so, what was the source of the problem? Also, the TV sometimes when turned on doesn't always have the right color. If you turn it Off and then back On it is usually Normal.
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