looking good, color is back, decent gray scale. I do have my old friend line pairing rearing its ugly self. My 1st attempt to resolve that was of course adj vert hold, but it jumps in and out of pairing so I will pull the chassis and start with those brown drops in the vert circuit, esp the boost filter cap (.1 1kv) that sits right next to a compactron. while I have it out I will also replace those pesky feed back caps in the vert plate circuit (.0082 is on of them). I will also replace that .001 on the vert primary to ground, just in case some horz is getting in thru the yoke into the vert out trans. I recall having a real tough dog with line pairing that was cured with a new yoke.

the horz prob needs a bit of work as well, its pretty much all the way to one side to lock and will not flop, so I am going to look at the caps/resistors in that circuit as well.

argh, pulled the sync sep tube with the set on to replace and see if my line pairing goes away. Well it did as did the video. Being a compacton it is a multifunction tube, I know better to pull tubes with the set on, but I did it anyway and smoked the video driver TRANSISTOR (the only one in the set). Of course there was no actual smoke just a blanked out screen. I had anohter Si NPN handy so popped that back in and all well.

So warning becareful about pulling tubes alway have power off just to be safe.

Will try to see if I can get the CRT out an pop the cat off next.

Tip when dealing with multi-section tubes: if you have many spares handy cut off or bend the pins on the section you want to disable and make sure to plug it in the right way...I've done it that way before and it works.

popped the cat, did not have to soak as the PVA was soft enough to dig out spaces for the wood wedges (clothespins), about 10 in total. Just have clean it, put it all back together and will call it done. This set has a near mint cabinet, but the CRT red is a bit weak but not bad. After I get it all together I think I will get started on that CTC-5. I put a little restore finish on the 5 and it looks pretty good. Has some nicks and chunks missing down near the legs, but the overall finish is not bad.

How about some pics :)

will get pics as soon as I get it all back together. CRT is back in, setup the HV/purity. Still need to check the HOT cathode current (did it when I 1st got it but will check one more time). I noticed some arcing down on the pwr board around the varistor, Not sure what that was all about. guess I need to pull the chassis again and check the solder joints. The horz has some thing odd going on, I will get wiggles in vert lines sometimes, not others. Tried adj AGC no help (it works it just does not eliminate the problem). I may need to scope the sync pulse and look at it when the problem show so see if the issue is at the sync or after. What bothers me is its not constant just some scenes with vert lines will get the wiggles while other times not. I have a feeling its some video getting past the sync sep tube.

the cap across the osc coil tested a bet leaky and weak, so I replace it as well a .0047 paper in ceramic tube cap. put it all back, arcing gone on variester, hmm no pic, very dark pic,AGC barely does anything, poor sync lock, WTF....

I looked around where I had just checked some resistors in the sync sep circuit where I had to take them out of circuit (PCB), careful looking shows very small solder bridge right around where I was working. Cleared that out but its getting late so I am just going to call it quits for tonight. I am starting to dislike this set
:no:

well that was it, the solder bridge must have been fouling the AGC. the new cap seems to have made the horz osc a tiny bit better as far as the ability to hold lock with the horz control. Still seems to have that problem with hard vertical lines, so think I will try a couple more things tube wise, then the scope and if that does not do it I will just pack it up and forget it.

don't know what the deal was with the horz pulling, I put the DVD box on it rather than the OTA from a modulator and it seems fine now. the line pairing is settling down as well. I will get some pics soon now, just have to take a break, too hot out in the garage. I decided to leave the brightner off, it has a better pic with it but not too bad with out. Plus I could not for the life of me figure out a good place to put it. I tried zip tie under the CRT neck but then the bump out would not fit. There was just no good place for it.

Make sure your source INTO the Blonder Tongue (or whatever)...is getting a good connection with decent RCA cables. I sometimes have to pay attention that the inputs to my little transmitter are not picking up hum bars from all the other stupid stuff I have in the same cabinet. I used to get all worried I was having filter problems in one of the sets....only to find out I was having issues with the source material.

I know it seems a bit elementary....but I've overlooked this a couple times before and JUMPED to the "worst case" conclussion.

pic is better than this, the motion added some bluriness

Under the heading of not leaving well enough alone, I was thinking about the horz eff coil setting last nite. the fact that the dip took place with a large bit of the slug out of the coil (I did drive it down it never got better) I got to thinking maybe one of the 3 caps that connect across the coil may be bad. I checked the .0022 that connect directly across it on the board, but I never checked the two .068 that are connected below the chassis. So even though I have it all back together I think I must pull it out again and check those. I generally just clip on lead, test, and then use a pig tail to reconnect if ok.

I have a slight purity issue on the bottom, tends toward greenish, I think its the yoke as it droops quite a bit due to plastic fatigue. here is a better pic with flesh tones. I ended up going without the brightner.

GE Roundie
 

Really nice job with this set, Dave. Very patient troubleshooting! I did not especially care for the screen image of Arizona beating my Seahawks, though! LOL!!

Very Nice set!!

Thanks, it was fun. I never got the eff coil figured out (why it has to be so far out for the dip) I checked the caps that are tied to it thinking something was wrong there, but they all checked out. I have some other yokes that I could use to see if I could improve the purity but its not that bad and its hot out in the garage so I will give it a rest. Besides the CTC-5 I have a very nice sylvania roundie console that needs to have the lens popped off (its good to go besides that). So I have others that need attention as well.

I putzed around with the purity a bit, the red blob was just a touch off center so I recentered and then reset the yoke, seems better now (green on the bottom is pretty much gone).

its been a while so I decided to fire this one up again. The tint range is not very effective, the flesh tones don't really change much, the greens go from weak green to weak blue but not by much. the Tint also seems to cause the color to intensify in one direction, like its change the amplitude of the reference as well as the phase. I was thinking of putting my scope on it to see, but I would rather just use my vector scope, but I have it in storage so will have to put that off. I would like to see if the tint control is increasing the petals as well as rotating them.

This set has the pot for a tint control, so it uses a variactor diode, rather than just a variable cap for tint.

any one have any exp with variactor diodes as far as failure modes? that is do they ever become less effective with age and use or is it an all or nothing kind of thing?

with the yoke drooping i use flat card board at the end of the yoke and this cures that and it dont conduct emf.:D

finally got the vectorscope on this, and again while it can produce ok face tones the green just was not there. the vectorscope showed what looked like the petals laying down sideways, I tweaked the transformer in the phasing circuit and after about 3/4 turn the flower stood upright and bingo nice greens.

I hint that something is not right is when you get decent flesh tones, yet the tint control does not do much in the way of adjusting.

don't settle for brownish greens, and don't go nuts trying to improve greens with drive and background controls. I will get the Wiz of Oz on it later for a nice screen shot.

here are some shots with the green (and tint) working now..

Pretty nice!

"good enough" :D

I don't think GE's looked that good from the factory! I'm jealous!
Great job!
Now I want to watch "War of the Worlds" on it. The Gene Barry version!:D

That picture had me thinking all night! What Vectorscope do you use?
I have an antique Lectrotech V-7.
I even pulled a KE schematic out and remembered how much fun some GE's were to work on!
Again, great job!

Heath kit. got it off ebay, just needed to reseat some of the IC's to get it working. There is a pretty simple setup per the GE service manual, just using the color bar gen and a VTVM. A single test point and tweak coils for max and min, but I did not do that, but rather just diddled the two coils to get the best image on the scope

I too got a Heathkit vectorscope from the auction site. It came with the manual and I have not used it yet. I got it for the minimum bid of something like $10.00 plus very little shipping. I could not pass up the item for that price even if it sits on the shelf. I would guarantee that it was almost never used (if ever used!).

they are fun to play with, have a built in dot/cross/grey scale/purity setting, and shorting switches for the grids. the main thing is it give you a quick check of the output from the chroma demodulators, so if they are not right you don't have to spend anytime messing with CRT setup trying to fix problems that are not real.

had a little set back, fly got hot, started to lose sweep and HV, turned it off, fly very hot.

checking a few things, the line voltage is high (125vac) and I did not yet switch to the high line tap, so that will be 1st. double checked the HOtube, about 215ma, at 115vac its about 200ma, playing with different 6JS6s got it down to about 195ma @115vac.

the eff coils slug is way high (mostly out of the form) to get a dip. I am going to replace the cap and maybe the coil associated with that circuit. and will replace the boost filter caps as well (if I did not to that already).

the service manual has a not about changing the HOtube screen resistor to 18k from 13k so will do that as well.

there is a diode that is connected to the aux winding on the bottom of the fly (agc/burst/hor afc... winding) thru a cap. the neg of the diode connects to the grid of the HO tube thru a 1.5meg resistor.

My guess is this is a safety circuit that cuts off the HOtube in case of hv runaway, sort of like the RCAs that use the neg voltage from the blanker tube as a safety in the same way. Besides the diode there is a cap and a couple resistors. The grid bias of the HOtube was a bit high (too low a neg) by about 10v (was -56vdc vs -67vdc) could be the vtvm calibration I suppose but that is big enough to look into. I will have to get the scope out to be sure. The scope is the only way to see if the neg bias is correct when that backup safety circuit is used (the neg reading is a composite of the two, the rectified drive from the horz osc and the rectified drive from either the diode mentioned above or the blanker tube).

nothing definitive, the horz osc plate load resistor had drifted up some to 92k shb 82k not much but then again, maybe just a tad less drive. While I was in there I went ahead and replaced the .01 coupling cap, it was a small brown drop rated at 400v, it sees a pretty good sized pulse so I put in a .01 1kv dipped. those boost caps are all disc, I really doubt they are leaky, and they had the spark gap cardboard spacer on the lead that I did not want too fuss with.

the diode used in the bias circuit of the HO tube tested fine, and the resistors that form a voltage divider (1.5 meg and 12 meg) were right on the money. There is a small 680 pf disc cap that supplies them from the flyback, it looked fine I just can see it being bad, will leave it for now.

did switch to the HV tap, so before doing anything else will see what it looks like now (couple cap,plate load resistor, and PWR Xformer tap).

I still don't like the looks of the eff coil slug being up so high, but I dont like to make too many changes at once without testing.

Oh forgot the 18k I will have to get one of those from the surplus store tomorrow, I want to to that before testing again as the service man said that should always be replaced.

found a sams on it (I was working from the service manual) so started with the resistance chart on the horz osc, hmmm another plate load resistor off a good bit, this time a 12k that was down to 8.8k. found a 12k that tested 13k in my stash of 2 watt carbons so I put that in. It also called shows a cathode current of 215ma, which is where I was, just seems a tad high.

I am starting to wonder if something in the HOTube started to short or get gassy or some other failure that may have pushed it over the top when the melt down started. oh well anyway press on and see what happens.

I put a 3.3k power resistor in series with the existing 12k, put it all back and touched up the eff coil again, now its about 187ma had to switch to the strong HOtube as the weak one resulted in too narrow a sweep (and about 165ma).

I have to double check the HV and make sure it regulating, the color seemed a bit off and the pic was not as good. I suspect my HV is down. If so I will undo the screen resistor change and check again.

HV holding right at 25kv regardless of brightness or scene changes. The tint is a bit odd, it seems to change a bit from left to right. I suspect its the odd ball GE color circuit (no color osc). Maybe the lower voltage from the tap is effecting it, but I did not notice it on lower line voltage. hmmm have to look at the schematic some more. Maybe a weak burst amp or something like that.

The eff coil is still WAY out nearly out of the form to get the peak. I did not change those caps (the one across the coil and two that go to ground from each end of the coil).

I noticed a very slight foldover on the right edge that was not there before. I was going to adj the coil just a bit to see if I could correct that.

Oh one more thing, the HOtube grid voltage is now about -64v increased the neg voltage about 8v.

what I may end up doing is wiring up the chassis so I can switch out the extra resistance on the screen. I would like to add a low/high switch on the back, I have this on some of my sylvania sets (for the PWR xfromer tap).

after a considerable about of futzing with it, I decided to return the tap to the orig spot, this will boost the overall voltage, which should help the CRT as its only ok. I will leave the screen dropping resistor in place. I think this will get me to about 195-200ma and temps in the 120-140 range once the fly cage is closed back up. the only other thing I did after the screen and those couple of plate load resistors and the coupling cap for the HO tube as to replace the .47 filter cap on the AGC, the old one way cracked around the terminals, not sure how that happened, but I figured it may have compromised the seal.

I plan to try a new lin coil in it at some point to see if that has any effect but that will be a later day. I really want to get back on that CTC-7AA

so I am putzing around with it somemore and I notice the horz scan lines have a slight wiggle in the last couple of inches on the far right side. Damn...

keep looking at it, try a new H osc tube, reset the horz osc coil (ground the test point a set for float by), no sine wave coil on the GE to fool with. still there.

get scope, has a funny looking bump on the flat top, but that may just be the scope picking something up. looking at the set in the mirror hmmm.

Take a break, start up the movie again, odd some french words (part of the movie warnings are in french for some reason), any way I did not know the french read from right to left, its been a while since I took french in HS but I do not remember that...

next come the Brothers Warner imblem, wait thats supposed tot be WB not BW..

Duh horz yoke hooked up backwards. all the time I was looking in the mirror and it looked right. I reverse the horz leads on the yoke and the little squiggle is gone. Sometimes the easy stuff will get you.

I am going to put it away now before I break something. The HO tube is at 195ma so I hope my overheating fly is done. I will get a new lin coil and replace that later to see if that makes the lin adjustment point more reasonable looking, but I have had my fill of this one for a while.

Dave, I had to laugh at the backwards yoke that was OK in the mirror! Thanks, we all make silly mistakes from time to time.