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Old 02-11-2014, 09:26 AM
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CaryLee CaryLee is offline
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Join Date: Dec 2013
Location: Farmington, New Mexico
Posts: 108
I do agree that I would have preferred to not have to adjust any of the IF cans. But that ship sailed decades ago. When I brought home the set from my grandparents house decades ago, the adjusters had already been tweaked, possibly many times. I found some were turned all the way out, some turned all the way in (hence the one the "fell" into the can a couple of times. It apparently no longer has the "stop" the others do). As a result, the initial picture was not as good as it is now. It was "blocky", and had a lot of "ghosts". My grandfather was a big "do-it-yourselfer", and my mother confirmed a few nights ago on the phone that he tried to fix it himself back in the 1960's, but I doubt he ever had the SAMS or Rogers references to start with. I spent a lot of time with grandfather, and worked with him in the construction biz back in the late 70's through mid 80's. I credit my grandfather for my "gumption" to tackle new tasks. When I was young, faced with some seemingly insurmountable task, and would ask "Can we really do it?", he would say "Somebody built it." or something appropriate, and we would dig in.

I would love to have the equipment to "set it and forget it". I'm hoping to have access to an oscilloscope and signal generator eventually, perhaps borrow them if I can find someone who has them, or even if it means buying them myself. Then I can follow the alignment directions in SAMS and be done with it. In the meantime, in order to get the picture I have, I've had to spend hours looking for the "sweet spots" and learning how the IF adjusters affect picture and interact with each other. Admittedly not the best way, but right now, it's the only way I've got.

I also followed the "AGC" adjustment and horizontal sweep adjustments in the SAMS (sans the equipment for the horizontal sweep, thus relying upon my best judgment of picture, of course) and it's all been good. In fact, that alone brightened the picture immensely. It will be interesting to see, eventually, how close I got.) One of my frustrations has been that the test pattern DVD made with files downloaded from the internet works great in the computer's DVD player, but won't play in any of the actual DVD players I've tried it in, so I'm having to make adjustments with static images from shows.

We watched a few hours of "Get Smart" last night and I did notice some bright white "blips" along the "scan lines" that faded away with warm up. But after a couple hours, during an episode that had much brighter backgrounds than others, they reappeared. Looks like I've got some more tweaking to do. Also, it seems the "scan lines" appear, quite faintly, against a dark background even when the brightness is turned down quite a bit. Interestingly, in the copy of the original "SAMS" folder I have, on the schematic someone had used a pencil to circle "C2" 50uf cap, and wrote "vert jitter retrace lines".

I know this is a long shot, but are there any "old time" do-it-yourself" processes for video alignment for folks who didn't have scopes and signal generators and such? I'm kind of having to make this up as a go along, but maybe I'm "re-inventing" the wheel.

And check out that brand-spanking-new eye tube! It's action seems correct, in that it does move maybe a quarter inch up and down when it's slightly "off signal". However, when it's not on a channel at all, it lines up pretty good as well. As I get to a a video signal, it moves either up or down, and then lines up again, apparently when I reach "center" of the best signal. Is that normal? I've read where the action of this particular eye tube is not very "intuitive"..especially considering the left bar's BOTTOM edge is the one that is supposed to move up and down...and I have to agree it's pretty funky.
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