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  #46  
Old 05-22-2011, 03:34 PM
DaveWM DaveWM is offline
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well I have a B&W maggie astrosonic combo, so maybe I can just set this one next to it, then use depending on whats playing.

I still have a lot to do after the TV, The TT needs to be gone over, mostly just clean out the old grease, and replace. Will need a new needle for sure, I just hope the cart is ok. Then all the little caps in the stereo tuner/amp which tend to dry out. When thats all done I will see if some restore o finish will be enough for the wood work.

going to check the B+ delay to see how that is working, will post afterward.
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  #47  
Old 05-22-2011, 06:01 PM
DaveWM DaveWM is offline
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ah ha, the relay has to do with instant on (switchable).

interesting, instant on take about 15 sec, with out it about 30, so not exactly instant. I can see all the filament barely glowing in the dark.

Last edited by DaveWM; 05-23-2011 at 08:33 AM.
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  #48  
Old 05-23-2011, 11:43 AM
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holmesuser01 holmesuser01 is offline
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I'm all for disabling the instant on feature. As we all know, that really helped to kill alot of tube TV's. Congratulations, Dave, on aquiring this fine set.
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  #49  
Old 05-23-2011, 11:48 AM
DaveWM DaveWM is offline
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Fortunitly there is a switch that disable is. I was thown by the relay in the B+, its kept off during instant on mode.

I still have a bunch of work to do, but this is prob the best cabinet I have had to start with.
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  #50  
Old 05-25-2011, 12:19 PM
DaveWM DaveWM is offline
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Huge thanks to MikeH for the HV cover, its in perfect shape, arrived safely today.
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  #51  
Old 06-14-2011, 12:19 PM
DaveWM DaveWM is offline
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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).
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  #52  
Old 06-15-2011, 02:26 AM
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MelodyMaster MelodyMaster is offline
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Quote:
Originally Posted by DaveWM View Post
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.
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  #53  
Old 06-15-2011, 06:07 PM
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ChrisW6ATV ChrisW6ATV is offline
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Could the interlace issue just be a limitation of the circuit? Years ago, Consumer Reports magazine used to test for interlace quality among other things. One of their comments for some sets was "you can improve the interlace by careful adjustment of the vertical hold control". I remember having several TVs that worked that way, maybe all black-and-white sets. My brother bought a new Sony KV-1920D color TV in 1977, and I remember it was the first set I had seen where the interlace remained the same (almost perfect in that set) regardless of the vertical hold control's position within the in-sync range.
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  #54  
Old 06-16-2011, 07:04 AM
DaveWM DaveWM is offline
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perphaps, but I know that there is variation between sets that are near clones. Its not a huge deal, but I will persue checking it out with a scope. I often find the best way is to compare to a set that does NOT have the issue (and is the same or very close in circuit). This shows up differences on the scope better than some of the iffy pics of a scope trace on sams. Mainly I want to zero in on the output form the intergrater and the B+ to look for horz noise.
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  #55  
Old 06-16-2011, 11:13 PM
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ChrisW6ATV ChrisW6ATV is offline
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Next time I fire up my CTC-16 combo, I will have to adjust its vertical hold and see how its interlace is affected, if at all, and how good it is in any case.
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  #56  
Old 07-27-2011, 04:41 PM
DaveWM DaveWM is offline
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got a pretty strong single ghost about 3/4" offset on the right. Turning the color down and its still there so I assume its in the Y channel. going to try a new video amp tube just to see if it has any effect. Maybe a faulty delay line?

its such a big cabinet I dont really want to move it and pull the chassis.

I guess I could try injecting a signal starting at the output from the video amp and start working back, but maybe easier to just put up a test pattern and see if I can see the ring, if so then work back.

Its not really a ring, as its only one ghost, more like a reflected signal. Maybe a tuner issue?
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  #57  
Old 07-27-2011, 04:55 PM
ctc17 ctc17 is offline
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Do you have a telephone sitting on top of the set?
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  #58  
Old 07-27-2011, 10:05 PM
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Penthode Penthode is offline
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Do you have a photo you can share of the screen?
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  #59  
Old 07-29-2011, 02:10 PM
DaveWM DaveWM is offline
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here it is
Attached Images
File Type: jpg ghost.JPG (136.8 KB, 41 views)
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  #60  
Old 07-29-2011, 02:50 PM
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miniman82 miniman82 is offline
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Looks like IF ghosting, my CTC-4 does the same thing just not as noticeable.
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