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Old 07-19-2013, 04:10 PM
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miniman82 miniman82 is offline
First Light: 1952-2011
 
Join Date: Jun 2009
Location: Great Mills, MD
Posts: 4,183
Weak tubes? <shrugs> Could be any number of things, what's the scope trace of the video output tube look like? Can you drive it full white via input to the tuner, with a pattern gen or the like? If not look for bias issues, bypass caps that aren't up to snuff, or incorrect alignment. Also make sure you don't have a bad video tube; H-K short, grid leakage, ect. Just because the sound is good doesn't mean the video carrier is in the right spot, though 9 times out of 10 if video is good sound typically needs to be touched up. You can usually get close enough with a slope tweak if you know what you're doing, provided no parts in the IF chain were replaced...
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