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Old 04-08-2020, 05:18 PM
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Electronic M Electronic M is offline
M is for Memory
 
Join Date: Jan 2011
Location: Pewaukee/Delafield Wi
Posts: 14,808
Horizontal hold behavior is intermittent. Sometimes it won't sync worth a damn sometimes okay but control lock range is limited sometimes I can get close to the 30 degrees lock in range Sam's suggests is correct. The hold pot has a VERY broad effect on the frequency compared to other sets (heck it will pull it so far the osc will die on a good portion of one end of the range). Trying the Sam's H osc adjustment procedure that involves grounding the H AFC, putting a .1uf between the H osc coil and ground, locking with the hold, removing the cap, locking with the coil (can't do it it isn't very close to frequency), removing the AFC short and calling it done. All the resistors in the horizontal are good the paper caps have been changed and the 680pF mica was changed... I'm not sure what could be changing the coil lock point.

After doing the sams horizontal osc proceedure I got the horizontal lock good but color lock was barely present/not stable for more than a minute. The picture often has bad ringing on high contrast so I have started my first video IF alignment with my B&K 415..the first 2 injection points went well the adjustment on the first was almost spot on, the second needed touch up but was cooperative, the third that goes through the tuner is not close and getting it there is proving difficult...I may have to dig for a 6BC8 for the tuner. Sam's calls out a 6BC8 but a 6BK7 is what is in there... I'll probably have to dig as there are no BC8 in my boxed/labeled tubes so it will be a bunch of digging into my bins of loose pulls.

I when I have more time I'm going to have to rant about how Motorola and Sam's think you should deal with removing the H output tube during alignment... they musta been bribed by ohmite.
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