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Originally Posted by pac.attack76
Ok, new ic put in. Finally got everything back in and tried it out today. Focus keeps going in and out about every second. Never seen that before. Also was surprised to see something called warranty clock. Ne ver in 40 years of working on tvs have I ever seen something like that. Kinda cool. Says has operated 65,000 hours and was first turned on 4-11-2000.
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That tube looks weak from that pic... Hopefully it will balance out when run a few hours.
Focus drift can be coming from anywhere, including the CRT itself. Sometimes in a quiet room you can hear the arc beat in time with the focus drift. A rubber tube probed around might tell you where the drift is coming from.
The focus drift is probably coming from inside the CRT socket assy or (yikes) behind the socket guide. Given the history of this TV being outside, the possibility of it trapping moisture from the air inside the socke, behind the socket guide, or inside the flyback is very real.
The CRT socket assy has a built in spark gap to ground out any wayward internal CRT arcing to ground so as not to back up into the kine drive circuits.
The assy is normally held together with melted "rivets" that can be easily removed. Carefully separate the halves being careful not to let the individual metal pins get away. You will see the spark gap inside, and if it's been arcing, you will see some greenish smutz in that area. Cleaning won't help but with a Dremel and a fine tip, you can grind out the arced area leaving fresh white plastic. Go over it with a bright light and magnification and make sure to remove absolutely all of the green smutz.
If inside the socket is clean, the problem might be between the plastic guide pin and the neck of the tube. When these were made, most of those guide pins were pushed on and held in place with clear RTV. If it's glued, it's hard to get behind. If you try prying to help, use a plastic spatula instead of a metal screwdriver. If you get the guide off, look for that same green crap behind the guide (if it's white - if it's black, you won't see it). A replacement guide is best but you can try soaking the guide in ISO for a while and brush it out. Clean the neck of the tube and carefully remove as much RTV as you can. I wouldn't replace the RTV however.
A third option is the flyback itself is arcing internally at the focus divider/adjustment. If so, you might be able to hear it with your rubber tube stethoscope. You can try removing the fly and putting it in a box with a hair dryer blowing into it on low for a few hours and hopefully drive any moisture out.
John