Maggie roundie combo

[MelodyMaster]

Originally Posted by DaveWM

time for an update,

its looking good, the astrosonic needs service, and I have a line pairing issue with the vertical, not bad but not right. You can adj it out with the vert hold, but I still need to look into that.

My plan is to pull the vert osc tube out (brightness down) and scope the grid signal going to the vert out and look for horz noise.

It has most of the orig caps in the feed back loop, so I can check along there as well.

I was thinking of checking the boost supply to see how it looks on the scope, I dont know this but was just thinking if the boost filter cap was weak, maybe the boost voltage would have too much horz hash on it, getting into the plate circuit of the vert osc. there are a few other decoupling caps around there as well.

I dont know how much is too much so I will prob end up having to check a set that does not have the pairing issue at all.

On an old B&W I had this problem but much worse, turned out to be a bad yoke that was leaking horz back thru the vert windings and back into the vert out transformer. that was a tough dog (for me anyway).

Back in the day when I was servicing TVs fairly often a poor interlace problem could be fixed simply by reducing the signal vertical pulse to the sync servo. It reduced lockin range but interlace would be good to perfect throughout the range. In other words too strong a vert pulse would cause doubling.