Quote:
Originally Posted by old_coot88
You've probably already checked 'em, but there's two more peaking coils, L103 and L104 that you might want to doublecheck for continuity.
If those are good, what happens if you inject video from the B&K at the CRT grid, working back point by point towards the 6H6 detector diode? Need to reduce the output as you move back (to keep the pic from tearing/flagging) and reverse the phase a couple of times (since a tube's plate is always opposite phase from the grid). Also watch for the point at which the 'trailing ghosties' appear (that's assuming they arise after the detector in the video chain).
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L103 and L104 read on spec. It appears that the ghosting is upstream from the 6H6 in the IF or RF stages, however I am thinking that the ghosting is due to an over-driving of the signal and not a receiver flaw. After some additional tweaking, and more importantly correcting the height of the picture, the horizontal instability, while still there, is less severe than before. adjusting the set without a reference for height tripped me up on the last (round screen) set that I worked on.
I made a template of the crt mask out of card stock to place in front of the screen to get a better idea of what I need to adjust to. I took a video of the set with full video to give an idea of how it looks at this point. The dark diagonal line in the video is not actually on the set, just the video.
http://www.youtube.com/watch?v=PTXslUBXsyE
The modulator that I'm using is not the best, I hope to replace it soon with a BT modulator just as soon as I find one in my price range. I think my plan of attack on the set is to do a full audio and video alignment according to the procedure outlined in the Rider's schematic. The audio is so bad that there is no sound output currently except some higher frequency FM stations at the low side of the channel selector. I would be doing the alignment under the expert tutelage of a local antique electronic repair expert who has been doing this for decades, and has the necessary equipment for the task. After the set is aligned I can revisit the horizontal instability if need be.