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Discussion Starter · #1 ·
I see everyone saying, ... "If your convergence is messed up, you need to replace the convergence ICs and possibly multiple resistors."

I can't purchase those parts until Monday so I decided to do some poking and prodding with my multimeter because "why not?". About the 10 or 11th resistor I check comes back as being open, only it's not even one of the "convergence resistors". Those are all supposedly 2.2 Ω at 2 watt. These two resistors I found are supposed to be 27K Ω at 1 watt! Resistors R015 and R013. Does anyone have any suggestions on why those two both may have failed, or what they're associated with?

Any other advice on trying to troubleshoot this board would be appreciated too, as I'm by no means a professional.

If it helps anyone also I found a service manual for this TV on Panasonic's Canadian website.
servicemanuals dot panasonic dot ca/viewing/NA/PT-53WX53G/SVC/53wx53g.h t m l

Thanks a lot!
 

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Discussion Starter · #2 · (Edited)
I just went through the schematic for the board and found that both of those resistors lie between the P_BTL and C_BTL 40V on what to me looks like it would be a wire harness or something labeled D1. The connections are as follow

16 TUNER GND
15 TUNER GND
14 NC
13 NC
12 STBY 7V
11 STANDBY GND
10 P_BTL 40V
9 AC ON/OFF
8 C_BTL 40V
7 -20V
6 GND (SOUND)
5 -20V
4 GND (SOUND)
3 +20V
2 GND (SOUND)
1 +20V

Just a little more information. It's nice to write this out too, helps keep ya focused or something.

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Here's a little more background after reading Icaillo's sticky thread on CRT based RPTV Convergence Repairs.

Red is stuck on the left side of green, and when I tried to adjust the convergence, red would only get near green, and if I continued trying to move red right it would go to the left. I could get red to ALMOST touch green if I tapped the button just enough times but if I held it down too long red would start going left.
 

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Discussion Starter · #3 ·
Ok I'll eventually hit 5 posts replying to myself and then I'll be able to upload some pictures. I saw a few globs of an off white silicon covering up the connections for what looks like a transformer and a diode on the bottom of the convergence board, or D board. The silicon didn't look like it was done in the factory because it's nowhere else on the boards anywhere. So I removed it and the connections looked strong underneath and also appeared to have never been altered. There's also a spot on the bottom of the board where a 1uF 50v capacitor was attached to a lead on a 1K Ω ¼ watt resistor and a lead on a 100uF 16v capacitor. That was obviously a post factory repair. Anybody know why they would have done that?
 

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You are making assumptions that may not be valid. There are factory mods to boards all of the time. You may or may not be reading what you think you are with respect to the resistors. Be very careful with your tinkering, as you may do more damage than you expect. These repairs are either very simple or will require skilled troubleshooting. If the convergence repair sticky is not adequate to solve your problem, you will likely need a professional to sort it out. The more you do yourself, the more likely it is that a professional will not want to look at it at all or will charge more to retrace what you did.
 

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Discussion Starter · #5 ·
Thanks Icaillo. I didn't mess with anything yet. I did however manage to put the board back in the TV and plug everything back in right so the TV doesn't start on fire. I managed that feat without documenting what wires I removed from where.

I'm not a professional TV repair man, but I am a professional nerd. I feel that gives me the qualifications to feel confident in my findings with the resistor values I was reading. Like I said, the 2.2Ω "convergence resistors" all checked out to be within tolerance. There was one resistor that I felt may have been not within tolerance, that wasn't related to the convergence area of the D BOARD, but then there's those two 27KΩ resistors that read 0.0.

On another forum it was suggested that perhaps manual convergence would help (twisting the light after loosening the wing nut but not before marking the original position). I don't really much feel like doing that. I'm letting the TV warm up for a good hour here, and then I'll make a convergence alignment template and try to enter service mode to adjust the convergence that way.

I'm sure plenty of people would shell out the $140 and buy a template. I'm not plenty of people though.

Any advice on the best way to make your own template? I'm thinking some of that plastic you use to seal your windows during the winter, unless I can find some clear mylar somewhere.

Thanks again!
 

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There is no reason you should need a template. There is no reason that you should need to move the "light" by which I assume you mean the CRT. The fact that you suggest these things indicates that you do not understand the convergence system and are going down a dangerous path. Like I said, these repairs often do not require more than is in the convergence sticky, and if they do it is likely not a DIY project.

The old saying "when you hear hoofbeats, think horses, not zebras" applies here. If you do run across a zebra you need to be using a professional. If you can't tell the difference, you are likely going to do more harm than good.
 

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Discussion Starter · #7 ·
Yeah I don't understand convergence completely yet but it's all coming together.

CRTs are pretty cool.
 

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Discussion Starter · #8 ·
A picture is worth a thousand words. Does this capacitor look like a last minute add from the factory?



This is the best I was able to get the convergence in the system menu using fine. It seems like the far right for red is screwed up beyond convergence and up in the left corner is a bad problem area too. Judging by this picture can a diagnosis be made as to what might be wrong?

 

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I have no idea whether this was added at the factory or not, but it really does not matter.

Can you adjust the point convergence for the area affected? If so, then you either do not understand how to adjust properly or you do not have the proper range in the controls. The latter could be a classis IC or resistor problem or it could be more complex. Not knowing what you adjusted and what the controls do it is impossible to know what the state of the set really is. What exactly are you adjusting and what did you start with?
 

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Discussion Starter · #10 ·
Really what's going on is I can straighten out the top and bottom of the red, but I can't straighten out the sides or even shrink the width to make the red smaller than the width of the screen. I'll upload a video to show you what I mean since I'm not using the right terminology.
 

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You have not been specific about what you are adjusting. Line, point? Which ones? It could be nothing more than not knowing how to use the controls. Panasonic convergence is not intuitive. You have to make sure you understand the manual and procedure clearly. If you cannot understand the process and cannot use the right terms, it is unlikely that you will get very far and unlikely that anyone will be able to help you.
 
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