Panasonic Project TV lines


  #1  
Old 03-16-02, 02:29 PM
Texas2
Visiting Guest
Posts: n/a
Panasonic Project TV lines

I have a Panasonic Projection TV model number PTL4074s manufactured in 1989. The bottom 80% of the screen is fine but the top 20% of the screen has some annoying horizonal lines going across the screen. One line is red another is blue and the others are white (some are dashed lines). The verticle hold knob will move the lines but not make them disappear nor will the convergence adjustments make them disappear. Any suggestions will be truly appreciated.
 
  #2  
Old 03-16-02, 02:48 PM
Smokey
Visiting Guest
Posts: n/a
Thumbs up

Good evening, Texas2:

Right off the top of my head, I would be looking for a bad filter capacitor in the vertical oscillator/driver circuit. Something is causing the sawtooth waveform of the vertical oscillator to be compromised and it sounds like 60 cycle AC.

As so many times before, I recommend you don't spend a lot of money on this set. Projection TV's begin a downward spiral in the 9-10 year range. After that point in time, they become labor intensive and cost far more than they are worth to repair.

Smokey
In the Great State of Tennessee
 
  #3  
Old 03-16-02, 05:26 PM
Texas2
Visiting Guest
Posts: n/a
Thank you for the advice. When I opened the back of the set I noticed that the red and blue CRT lights were on but the green one was not (explains the blue grass on the football fields last season). A quick look at the Panasonic web site showed the cost of the green CRT to be $280. So even if I find the filter capacitor I have a bigger problem behind it. I think my downward spiral has begun. Thank You.
 
  #4  
Old 03-17-02, 12:54 PM
Smokey
Visiting Guest
Posts: n/a
Thumbs up

I concur with your findings, Texas2. Thanks for using DoItYourself.com. While our information is not always what the customer wants to hear, we are all volunteers (work for free) and have no reason to tell any lies.

And, this post is Number 2600 so I've been at this for a while. LOL!

Smokey
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: