slyvania roundie
 

Photos soon (got to find the camera).

the goood and the bad and the odd...

The good is the cabinet, very nice. Also the chassis, no rust or other damage, looks like the set was nver moved.

the bad

CRT is acting flakey, red gun pulses, socket glue is loose, Fly is toast (burned up), flame and smoke on the intial test run.

the odd

the CRT was unpluged, hmmm, most of the screws were missing from the back.

My guess is someone tried plugging it in, and after smoke came out it decided in typical DA logic that unpluging the CRT (and prob breaking the socket joint) would make it ok. Just a guess, OR at some time the CRT was tested, and at that time the fly was also bad so the owner just told the service guy to button it up and not fix.




I am searching my stash of flys and have put out some calls. it takes a fly 277. the sylvania PN is 50-16016-1. hopefully I can find one or cobble something togehter. I am not sure what to make of the CRT. Hope its not on its last legs.

Sounds like a nice score!

FWIW, there is a NOS Thordarson FLY-277 available for $1 here:

http://www.collectibles-articles.com...541510134.html

fly and back

wow! you are so lucky that flyback didnt start that magnesium chassis on fire and burn your garage and all your other sets up. This what happens when the manufactures dont bother to put fuses and use highly flammable metal chassis.

Fly 277 has to be the most desirable of all the flys. Not much chance of getting one of those, I have seen them on ebay but they grab a hefty price. I love the sweet smell of burning flybacks, please send me the old one

Try re-flowing the solder on the CRT pins, also, add a little new solder and that intermittent may disappear. Two part epoxy is good for gluing the socket back to the glass. Looks like she'll be a nice one.....Sylvania made some nice stuff.

This appears to be an RCA CTC15 clone...

If it is, I have a few of those flybacks in the RCA brand, NOS. The RCA part number is 113382.

PM me if you want one.

What are the main differences between the ctc15 and 16 other than the hv rectifiers connection to the flyback?

Almost nothing.

I figured. It looks like most of the parts are electrically identical between all the rca clone round tube sets and rectangular tube sets, but not between round and rectangular. Seems like 80% of the sets were basically RCA circuit designs.

PM Sent

Besides a major physical reconfiguration of the HV cage and relocation of the 6BK4, The 16 was the first with auto-degauss.

And as a matter of course on both CTC-15 and 16, always reflow the two ground stakes on the far right end of the chroma board. These crack and cause the 6GU7 heaters to go out. This is also true of the CTC-17 and 25.
oc

Unfortunately, that site is one of those Ebay-reposting-conglomeration-with-their-own-ads pages. It showed the flyback as available, but the real Ebay auction ended in March...

Is it really magnesium, or were you using poetic license?

Phil "just curious" Nelson

I hear it's up before the poetic license Review Board.

:twak:

update. I managed to find a fly in my stash that was close, so while waiting for the correct fly from another member I was able to get it up and running. the HV was a bit low, and width was low (cathode current was about 175ma, basicly I had NO head room for bright scenes). Everything was working as it should but for the lack of headroom (the shunt tube current would drop to 0 on max bright scenes, and the HV would sag to about 19kv.

I received another flyback (the correct one) from a VK member, and just finished installing all the parts to it, and reinstalling the assy. I left my test fly intact as I know it works "somewhat". The only think I did was to use a miller focus coil 6350 instead of the orig since the orig was on the subbed fly, and like I said I did not want to disturb that until I get a chance to at least try the correct fly.

the only other issues were a weak contrast cap, and the normal weak color amp grid caps (.01's the one on the middle of the board seems to always be weak.

the vert lin was a bit to close to the end of the range, the 2.2meg resistor had drifted up to over 2.4, not much but as long as I am in it I replace that.

the vert electro cap tested fine. the doublers test ok, but were a bit slow to fully open, for example a new cap of the same value would open in about 13 seconds, the old ones would take about 30. I have all the caps I need to completely rebuild all the cans and will prob do that later...

only thing left to do is replace the 2kv tube cap on the primary of the audio out, its one of those ceramic tube types.

once I do that I will do the whole HV setup again and hopefully will have the head room to keep the HV constant.

progress the focus is better than it looks, camera issues.

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..

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.

Dave, lookin' good. How 'bout some vanity shots of the cabinet?

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.

Awesome job on that set:thmbsp: I love the cabinet I hope one like that shows up around here someday.

"Glorious Lollipop Color".... I LOVE it !!

not many sylvania roundies out there.glad you got this one.pics are awesome!

any info on a REA21FKP22? is it just your garden variety roundie, thats a new number to me.

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

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 :yes:

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.

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.

still fighting that darn tendancy towards line pairing...

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...

Replace that feedback cap in the back of the circuit that has caused us this problem before. I dont care if it tests good, replace it.
The cathode bypass caps on the output triode have the same effect.

I will replace all those tomorrow.

replaced a couple in the vert, no joy, need to get the right cap (.035) for the final one. I did replace the .0082 1kv and the .1 that is connected from the boost to the 390v b+. Nothing.

I scoped the PS B+ the ripple was right on the nose about 1v pp riding on the 400v. there is of course some horz but it was very small and the sams showed it (I assume since it was a fat line on the sams).

For fun I scoped the output from the sync sep. looked normal (no excessive horz noise) and also looked at the vert out grid, again nothing odd. the pairing is very subtle and comes and goes. it is not always adjustable out iwth the vert hold in fact I am not real sure the vert hold is really taking it out when it does work, but maybe its just resolving as I adjust.

I checked the yoke for leakage, even went so far as to sub the yoke, again nothing. I have the .035 cap but its an odd ball fit so I plan to just order the correct one. I also was stunned to find I did not have a 47uf axial lead cap (the cathod bypass cap).

went ahead an replaced the .035, and the remaining .1 in the grid of the output triode of the 6GF7. changed the lineairity (more range now) but still have the line pairing going on. only thing left is the 50uf cathode bypass.

I am going to reset up the lineairity, then do the purity and convergence.

Its close just not perfect, like my CTC-16 in the stockholm. I will try a few more 6GF7's including the one in the stockholm just to be sure its not a tube issue.

I would really like to get these two side by side and scope the vert circuits, esp for horz noise, but they are both quite large.

Did you replace the vertical center control? I have seen that control cause some weird problems. In one of my ctc16 set's it shorted out and did damage to the power supply. BTW,You have a cool set.

did not look there yet. did it test bad, or did you just change it out?

I know it works, as I used it in the setup to center the horz line doing the setup routine.

[QUOTE=DaveWM;3008703]did not look there yet. did it test bad, or did you just change it out?
It had a burning smell to it so I just changed it out. Now I check the vertical center control when I pick up a new set and make sure the picture does not jump around when adjusting the control.

its pretty smooth, but I will check it again. good tip.

well at least I can report that I have good control of height and linearity, but still fighting the pairing. I tried a diff video source, blonder toung modulator, still there. sometimes I can dial it out some times I can't. and even if i do (vert hold) its only temp, as it pairs up again. I am going to try one more
6GF7 tube, then I think I will try subbing the tubes from my stockholm to see if that makes any diff (the sync sep and the vert osc/out).

Other than that I would have to drag the two beast together and start scoping them together, but I reall just dont have the room for that.

Davewm. Try looking at the AGC and see if adjusting the AGC control calms down the pairing. Grasping at straws here but the agc can effect the sync pulse going the vertical and horizontal circuits. What does your set do when you have the color pattern generator used as a signal source?