Thread: Ctc-7aa
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Old 12-29-2011, 09:18 AM
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IsthmusTV IsthmusTV is offline
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Join Date: Nov 2010
Location: Madison, WI
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I did find some time this week to work on the chassis. It had been sitting on my workbench in a horizontal position for four or five days undisturbed. When I lifted the chassis, I discovered that a big blob of transformer goo had collected:



Apparently, being horizontal got it flowing in new directions. Keep in mind, that I still haven't applied power and that the temperature in my workshop is about 60 degrees. This is a pretty large quantity of stuff. Is it possible that some sort of internal seal broke allowing this stuff to flow? Here's a shot after I scraped it off the carpet square with a penny for size reference:


On other fronts, I replaced the kluge repair with a proper resistor. I also found a charred 5600 Ohm resistor feeding the plate of the 12AZ7 color demodulator. It measured 144 Ohms! I wanted to find what had caused this overload. The 12AZ7 measured a bad HK short. In addition to the tube and resistors, I replaced a couple suspect caps in the vicinity:


I did use Phil's approach to the PS electrolytics. It all went pretty smoothly:


I also added a standard fuse holder, leaving the old one on place:


Two of the cans were definitely toast! I didn't even need heat to pull out the innards:


I ran out of time for now. I'll finished the third cap this weekend and attempt a first power up. BTW, all the windings on the power transformer look OK with an Ohm meter so I'm still reasonably optimistic that it will be OK.

-Clark

Last edited by IsthmusTV; 12-29-2011 at 09:23 AM. Reason: Added another photo
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