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Discussion Starter #1
:wave:Hi Mr. lcaillo,
I want to first of all thank you for the in depth guide which helped us somewhat understand the basics of CRT based RPTV convergence. We appreciate that you would take time out of your busy schedule to author such an invaluable resource for the DIY audience. As we read in other posts there are those in your business who probably don't appreciate it. Some DIY folks might do it to save money, but for us it is due to unfortunate circumstances, which doesn't afford us the money to have our system repaired by a service center or purchase a new one. You are a gracious man, for whom we can't articulate the gratitude you deserve, we hope our thank you will suffice.:T
Brand: Sony Model: KP-46WT510 (May 2004)
One day our area had a power outage for 20-30 minutes and later that day when the TV was turned on we had the following symptoms:
Picture curving inward (top and bottom), no R, G, B convergence control.
Diagnosed the -22 Volt fuse PS5001 5A on the G board was blown. After replacing PS5001 there was no more curving of the picture, the blue and green convergence were functional, but the red was still out. Further troubleshooting revealed Board D IC 8001 pin 9 (RH Out) was at -22 Volts and the PS8001 3.15A fuse was blown. Replaced PS8001 3.15A fuse and it blew the -22 Volt fuse PS5001 5A on the G board again as well as the PS8001 3.15A fuse. After re-replacing the -22 Volt fuse PS5001 5A on the G board again we are back to the same condition with no more curving inward and the blue and green convergence functional, but the red is still out.
We located the D board IC Voltage list and IC8001 pin 9 (RH Out) should be -0.05 Volts not -22Volts :rolleyesno:(should have done that before replacing PS8001).
We need to get another meter because the one we have is an old analog meter therefore the readings are not exact.
The attached Excel File shows our approximate readings and Service manual IC pin voltage readings.

Here are some questions:
1. Sounds like the IC 8001 is zapped, correct? We will follow your advice in other posts and replace both.
2. Would the STK392-570 be a better chip than the original STK392-560? Appears to be cheaper?
3. We asked the power company if they had a problem that could have caused our TV to go out and their explanation such as it was, well if a raccoon or animal got in the system and caused the outage it would be an act of God and the insurance wouldn’t cover it. They never would tell us what had caused the outage. Strange coincidence. :daydream:
4. Is there anything you would recommend checking/replacing, i.e. protection devices if it were due to something with the power or would you think it was just a coincidence.

Thanks again. :bigsmile:Heath the Dragon and Dad.
:waiting:
 

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Plain ole user
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Yes, you can use the STK392-570 in this set, but understand that there appear to be lots of bad parts on the market. Buy them only from one of the recommended suppliers like Acme or B&D. The -560 seems to be less counterfeited but will be more expensive because it has been discontinued longer.

Read this regarding protection:

http://www.hometheatershack.com/forums/general-service-technical-information/15037-protecting-your-system.html

I have seen power surges cause failures in these output ICs, but they are also a high failure point in all CRT based RPTV and can fail for no reason other than heat and age. Regardless, it makes no sense to me to not protect your system, as the cost is low for decent surge suppressors, and grounding can cost little to nothing. Unplugging a system is hardly practical, and unless you disconnect ALL signal lines like cable, sat, and phone that connect to the system, you can still be affected by surges due to lightning.
 

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Discussion Starter #3
Thanks for the quick reply. I guess I should have been a little clearer in my question. Would either the IC -560 or -570 be better than the other?
 

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It makes more difference where you get them than which chip you use. The -570 does appear to be a little more robust, but if you get a bad one it really does not matter which version it is, it is still a waste of time.
 
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