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Discussion Starter · #1 · (Edited)
I have a Sony Trinitron 32" CLR (KV32S26) that, when turned on, I can hear the sound but no picture. After about 10 minutes it starts blinking on and off, after about another 10 minutes the picture stays on. I have already tried unpluging it (i.e. hard reset) and spraying all the dust off the circuit boards.

Can anyone tell me what's going on or what I might need to replace to get it working again.

Thanks!
 

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Your thread was moved to the Sony forum to maintain forum organization and to make information more likely to be found by those who are able to help.

I am not familiar with a 32" CLR. Post the complete model number and you are more likely to get good advice.
 

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That makes it easy. Your set is going into what is called IK blanking. Sony sets use a system that sends pulses to the tube in the vertical interval on all three guns. It reads the current drawn by each cathode during those pulses and adjusts the drive to the CRT to balance the three guns. This allows the set to maintain pretty good balance between the three guns as the CRT ages. When it cannot achieve balance, most older Sony sets with this system will blank the video. The result is that most Sony sets look great as long as they are working. The down side is that you don't get to use the set when the CRT is aged to the point that the guns don't match.

There are some rather dodgy schemes for defeating the IK circuit but they have side effects that are generally not very pleasing. The only real solution other than replacing the CRT (which is almost never cost effective) is to have someone with the right equipment and experience attempt to restore the CRT. The only equipment that I have had success with are the Sencore CR70 and CR7000 CRT restorers. I have restored many of these tubes and if the tube is not too far gone in age, which is likely if you are just starting to have this problem, we usually see a careful restoration adding a year to maybe three years to the life of the set. The results vary greatly and there is always the possiblility that you can damage or short a tube when restoring.

I would only trust this kind of service to a tech who has a great deal of experience with the Sencore devices on the Sony tubes. Call around to the local shops and ask about this kind of service. Some servicers will try to apply an uncontrolled arc from the anode to rejuvenate the tube but this is very dangerous and risky and I do not recommend it. You need a tech with the right equipment and the right experience to extend the life of this one. Even with a successful restoration, I would be looking for a new set soon. This series of sets was not among the most long-lived of the Sony CRTs.
 

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Why not call around first? I do these all the time. If you can find the right tech who knows what he is doing and has the right equipment it is a quick job that is not very expensive and you may get some extra life out of the set. Even if you replace it soon, having it working takes the pressure off of the buying decision so you are likely to get it right, and you can always donate the set to a charity if it is working and write it off on your taxes to recover the repair cost.
 

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I have this same set (KV32S26) with this same problem. I am *somewhat* of a techy when it comes to TVs. I am much appreciative for the insight on the age of the picture tube and what happens over time and as it degrades.

My set actually blanks when there is a lot of white or brighter colors in the current video and comes back on a second later, if it is still white or bright then it blanks again. However, if the video signal has darker colors then it will stay on. Though it will blink consistently when it is first turned on (warm up period?).

Does this problem sound like the IK blanking as well? Also, for lcaillo: you said, "This series of sets was not among the most long-lived of the Sony CRTs." About how long should these last? And what is considered a "good run"? We purchased ours in October of 1997 (14 years). I figured that was a good run for a set but did other Sony sets do better?

Thank you again for your wonderful explanation and help. This set is slated to be tossed and a flat screen put in its place. But I was just curious because I am a "fix-it man" and just wanted to know what the problem was and if it could be fixed just for "laughs and giggles".

Sincerely,


Jim B.
 

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Without the CRT restoring equipment, there really isn't any thing that can be done.

Where are you located? If you look for the "older" shops in your area on probably has that equipment.

But a word of caution,,,, the basic beam restorers can short a CRT. I believe the 7000 will let you step up the voltages in increments, limiting the chance of shorting.

Good luck,
Jim
 

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Jim is absolutely correct. Someone with the correct equipment (Sencore CR70 or CR7000) and the skill to use it MIGHT be able to add some life to the CRT. Maybe not, depending on how far gone the CRT happens to be. My experience is that when they start blanking you likely can get another year or so out of them, but maybe only a few months, if the restoration is done carefully. Carelessly or with the wrong equipment and the tube may end up completely useless.
 
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