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  #16  
Old 07-05-2011, 07:57 PM
DaveWM DaveWM is offline
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progress the focus is better than it looks, camera issues.
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File Type: jpg pic1.jpg (36.3 KB, 112 views)
File Type: jpg pic2.jpg (26.4 KB, 93 views)

Last edited by DaveWM; 07-05-2011 at 08:24 PM.
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  #17  
Old 07-05-2011, 07:59 PM
DaveWM DaveWM is offline
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HV setup

1st pic is the HV prob, then the HOT current (used a socket adapter with the cathode break in it, bypassed with a .47uf cap, 500ma range on the simpson 260) and the shunt tube voltage drop across the 1k resistor in the cathode circuit (test point KK and a pin on the 6bk4 which is exposed on the back of the fly cage). lousy pic of the HV prob I know, I tried several times..
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File Type: jpg HV.jpg (34.2 KB, 50 views)
File Type: jpg HOT cathode current.jpg (28.1 KB, 41 views)
File Type: jpg shunt tube 1k resistor.jpg (49.6 KB, 35 views)

Last edited by DaveWM; 07-05-2011 at 08:41 PM.
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  #18  
Old 07-05-2011, 08:20 PM
DaveWM DaveWM is offline
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I used a new focus coil (long story) which worked well (focus range right in the center).

other issues were pretty normal minor stuff.

Broke the pull on push off switch removing the knob, was able to find a new switch on the back of another pot, which is good since the old one looked pretty well toasted.

contrast cap was weak, the chroma board had the normal weak coupling caps between the demodulators and the color amp tubes.

replaced the white tube 2kv caps just to be safe. the one on the Vert primary was leaking the one on the audio primary was not (at 450v anyway).

all the PS caps seem ok, they get a little warm but so far so good, I have the full compliment for replacement if need be. I can make up some replacements on scape twist lock mounts so it would be a quick replacement.

CRT test fine. socket is loose so will deal with that when I get to removing the lens.

dynamic convergence needs to be touched up, had yellow screen in the B&W reception, think the blue was just converging well. I have a NOS diode pack that I may try out if the old diode pack test bad. I did not check any of the converge parts, will if converging does not go well.

Most of the tubes were ok, some shorts IIRC. HOT was fine, as was the vert multivibrator. 6AQ5 was weak, replace all shorted and weak tubes with NOS.

replaced a few out of tolerance resistors, the 2.2meg that come of the boost to the vert, and the 1K in the shunt tube come to mind, there were a few others but no show stoppers.

oh there was an open power resistor in the peaking circuit, that was new to me.

Color would not sync, adj the color osc coil about 1/4 turn (after trying a few different 6GH8's)

Able to get all 3 colors in setup mode on the lowest bias setting.

it did not look like it had been serviced before beyond a couple tubes.

HV was set to 23kv current is about 170-180ma shunt is anywhere from 100mv to 1.5v depending on brighness setting and picture content. for normal view its tend to hover between .5 and 1.2, very stable HV.
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  #19  
Old 07-05-2011, 08:47 PM
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John Folsom John Folsom is offline
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Dave, lookin' good. How 'bout some vanity shots of the cabinet?
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  #20  
Old 07-05-2011, 08:52 PM
DaveWM DaveWM is offline
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will do tomorrow John, just got it all buttoned up. It is indeed a very nice well cared for cabinet. there is the brown stain around the speakers, my guess is cig smoke, but not sure about that. Anyone have any exp removing this?

If I can remove it down to the grill cloth, I was thinking some oxy clean or something like that. will of course try on some old grill cloth 1st to make sure it does no harm. No hurry, its not that bad.
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  #21  
Old 07-06-2011, 11:14 AM
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Awesome job on that set I love the cabinet I hope one like that shows up around here someday.
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  #22  
Old 07-06-2011, 11:27 AM
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"Glorious Lollipop Color".... I LOVE it !!
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  #23  
Old 07-06-2011, 01:50 PM
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not many sylvania roundies out there.glad you got this one.pics are awesome!
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  #24  
Old 07-06-2011, 01:54 PM
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any info on a REA21FKP22? is it just your garden variety roundie, thats a new number to me.
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  #25  
Old 07-06-2011, 02:17 PM
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The 21FKP is electrically the same as all the others, data sheet says grey bonded faceplate just like 21FJP.

http://tubedata.tubes.se/sheets/168/2/21CYP22.pdf
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  #26  
Old 07-06-2011, 05:24 PM
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Glenz75 Glenz75 is offline
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Great progress on the set Looking good, always nice to sort out all those niggly things with these old Tv's gives a feeling of satisfaction
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  #27  
Old 07-06-2011, 07:32 PM
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The convergence neck components look just like those used in Zenith sets. I expect the crt neck components are interchangeable between brands as long as the picture tube is the same. That is a great picture by the way.
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  #28  
Old 07-06-2011, 08:10 PM
DaveWM DaveWM is offline
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thanks, its getting there. I need to fuss with the B&K 1076 and work on the vert and horz lineairity.

The lines seem to spread out a bit on the very top and the horz is not very good, does not show up with out the test pattern.

I will prob scope the grid of the 6GF7 (vert output) and take a look a the waveform, but its so subtle I dont think I will see anything there.

will try a few tube subs there and see if it clears up. I have checked most of the resistors and caps (not the 680pf in the feed back) Everything looks good, no jitters etc... replaced the only resistor in the vert cire that drifed more than 10% a precision 2.2 meg.

it does not have an auto degausser, I have a kit that I may try installing, every time I move it it needs to be degaussed.
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  #29  
Old 07-07-2011, 12:20 PM
DaveWM DaveWM is offline
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still fighting that darn tendancy towards line pairing...
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  #30  
Old 07-09-2011, 08:35 PM
DaveWM DaveWM is offline
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fooled with it some more, tried some new vert tubes (6GF7), no change. every now and then I can get it to not pair up, but most of the time it does (messing with the vert hold, but its not a very reliable way to get it).

I couple of things noticed. I need to very nearly max out the lin adj (on this set its the one that feeds the plate from the boost, I know on some sets its called the vert height, I dont know why they cant make up their minds on this) to get the linearity as good as I can get it. Also I noticed its a tad jumpy, you can really notice it when there is some text near the top of the screen. I dont know if this "jumpy" vert is tied into the "jumpy" line pairing but it seems like it could be.

While I did test the various caps in the circuit with my old school cap tester the 2kv .0086 cap from the plate of the output side of the multivibrator could not be tested at rated voltage (tester only goes to 450v). there is also some little 680pf disc caps that I am not sure of the function.

I never did scope the grid output from the integrater the way the sams said to (bright down, tube out) to look for excessive horz hash.

I think I mentioned before the last tough dog line pairing issue I had was on a B&W maggie, it was from the yoke, some how it was getting horz back thru vert out transformer and back into the vert osc. I only found it by comparing a working set to the bad set and seeing all the hash on the bad set secondary.

I have another CTC-16 (this is a clone) so I could do the same, or just try a different yoke (I have an NOS). Its really a pita as the rest of the pic looks fine.

I dont know if the boost voltage could be causing this (if it had hash on it from a bad cap). I think I checked it, but not sure. again I could prob scope the it and see, again not being experienced in this I would need to look at a working set to see what it should look like...
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