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Old 06-29-2017, 07:55 PM
Bill R Bill R is offline
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Join Date: Oct 2004
Location: Jackson, TN
Posts: 893
It looks like you have made some good progress. However, you are still off on some of the basics. Do you have the Sam's for it? Sometimes the procedures are easier to follow in the Sam's. First things first, and remember all of them interact with each other. I notice from your last picture that you still do not have the vertical size and height quite right. Those blocks should all be the same size. The key is get the Black and white picture right, then worry about the color picture. I would turn the color off and forget for now. Try to get the linearity right first. Do not unplug the convergence board. Then work on purity, center static convergence, purity, static convergence, purity, static convergence. Repeat as needed until the one dot in the center is perfect. Then you can worry about dynamic convergence. Follow the steps in order and do not skip any. You will probably do it several times. Then recheck purity, and static convergence and tweek as needed and start over. It sounds intimidating, but by the time you run through it a couple of times you will get good at it and the entire thing can be done in less than an hour. Be sure the High voltage is correct, and the focus works properly. You may find it easier if you turn the brightness or contrast down some. You will get sharper lines. If you encounter any problems, make the necessary repair before proceeding. Now, it is time to do the gray scale adjustments. After all this you should have a nearly perfect black and white picture. Now you can turn the color up and start working on the color circuits. If you put any capacitor or part in that was not there originally, remove it. It wasn't necessary when new and shouldn't be necessary now. Be sure and check all the circuit grounds, and tube sockets. They are trouble areas. I would try a color alignment. Follow the steps in order. It is not hard. Usually you will ground a test point to let the oscillator free run and adjust the coil until the bars are stable, or only move very slowly. You will then remove the jumper and if the color oscillator, and bandpass amp are working the color should lock in solid. If not you will need to do some troubleshooting and do it again. Once color locks in it may be wrong so that will be adjusted next. You will center the tint control and adjust the transformers in the demodulator circuit for correct flesh tones and proper tint range. It is a balancing act. Now you should have a good color picture with proper tint range. Notice that unless you are using a vectorscope I have not mentioned any color bars. The early procedures use a keyed rainbow pattern, not the NTSC pattern you are using. You do still have an IF alignment issue since the color does not quite fit the black and white picture. On your color bars you can see it as the intensity of the color bar dropping off near the edge of the bar, or bleeding onto the next bar. Do carefully check the caps and resistors in the IF strip since some could have drifted off value. Replacing the drifted components may fix the problem without doing an alignment. DO NOT attempt this alignment without the proper equipment. You would need a Sweep marker generator, Oscilloscope with demodulator probe, and a bias power supply.
You are making great progress, just remember to try not to get ahead of yourself. You will end up chasing problems that may not really be there.
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