This is my new Sears TV set that I will hopefully be getting in the mail soon! The pictures are not mine, but I thought I would post them anyways since I am so excited about this set! The green seems to be a little bit weak as was noted by the person who is shipping it for me, but I am hoping that it can be remedied from some adjustments..


https://farm8.staticflickr.com/7539/15066492943_ddf14952e7_b.jpg
https://farm8.staticflickr.com/7572/15065919304_4b94f48760_b.jpg
https://farm4.staticflickr.com/3951/15685854515_57f49a1e91_b.jpg
https://farm8.staticflickr.com/7495/15685854815_1d92c0473e_b.jpg
https://farm4.staticflickr.com/3937/15500660227_0e1d60871c_b.jpg
https://farm6.staticflickr.com/5609/15687451942_12f877cd33_b.jpg
https://farm4.staticflickr.com/3938/15499999149_671cfbc176_b.jpg

love to see it................

Sorry Zeno, I have been having trouble posting images for some reason, and I was trying to get everything sorted out before I finished typing my post...

Toshiba built

Yup its a Toshiba ! Nice tv.... Around '72....
Above the red and green plug on the right, is a square plug with a single red jumper,
that is the focus selector.... Each one does almost nothing..... It's a neato tv, above
average quality build, but that tube just don't focus well....

Good luck ! Great tv you are lucky I bet they are not that common....

Looks like it has plenty of green to me.... That set has color screen
knobs, 2 drive knobs, and that 1-2-3 slide switch above the focus
jumper is kine bias selector.... Very well designed....

You got more than enough adjustments to do everything... except make
a sharp focused picture......

.

I wonder if there is anyway to improve the focus on sets like this? I know its a problem with most if not all sets with low voltage focus CRTs. Did sets always have pictures like this? If not the surely there must be something that causes it or some way to fix it?

After doing just a little bit of research, I found that some people reported that putting a CRT rejuvenator on clean or a light rejuvenation would bring back the focus back razor sharp, but I don't know if that would work on this jug...

I saw the offer and was wondering if you had, congrats.

You might want to try a grayscale adjustment before rejuvenation.

Yes, I know the set will need a full setup convergence, linearity, purity, degassing before I do much to it... I am a bit worried about the weak green, but I have a feeling it just needs to be setup properly as I don't think this set has probably been used in 20 years just as a guess...

I almost forgot. Al made a video of the set for me if anyone is curious to see it in operation...
https://www.youtube.com/watch?v=MkX2_siwqf8&feature=youtu.be

I wonder if there is anyway to improve the focus on sets like this? I know its a problem with most if not all sets with low voltage focus CRTs. Did sets always have pictures like this? If not the surely there must be something that causes it or some way to fix it?
This has a low focus voltage CRT? I thought all delta gun CRTs like that have the blue gun at the bottom.

It might not, I was just rambling mostly about the focus.

Most are blue at the top..... If I remember right this set has a focus
selection of 0v 150v and 300v, but no way sure... I'm sure about the 0v.

I would not attempt any rejuv. on this tube.... just let it be... It's no worse
than a '66 rca 17" color set I had....

The best you can do is full setup and let it live as is... Bring all three
guns into alignment and you will see an improvement..... Then set up
proper gray tracking, and you'll be ok....

Use the kine bias switch in conjunction with the focus to get the best
focus.... Adjust the screen controls go get rid of those retrace lines, they
are clearly set too high right now.....

There might even be a sub-bright on this set...... With proper setup this
set does get a better picture..... " I Guarountee it! "

Did you get the sams yet....? If'n you get it, you gotta post it, I miss lookin
at that schematic..... Pretty please....?????

.

Yes, I can post a link to it if you would like to see it. I just wonder HOW good of a picture this set can produce? :D

Yes, I can post a link to it if you would like to see it. I just wonder HOW good of a picture this set can produce? :D

I would love to see the schematic again....

It's not really a matter of how good a picture a set can produce. It's more about
keeping a part of history, and just appreciating it for what it is....

Low focus voltage tubes had some issues, and you have it to see first hand, it's
not bad, it just is.... Personally I would rather have that set with imperfect
focus, than one known for eating flyback's or vert output transformers...

.

Re. the low focus CRT, I have never seen one produce good focus, period. No matter which of the 3 taps was used, they always had soft focus. Just the nature of the beast.

Well, you guys were right about the focus. :p
I checked out those focus taps today and it does not even matter if the plug is plugged into a hole in the block, the focus does not change at all...

Also, on my set the red seems a orange, and the yellow is a bit green. Is there any way to adjust thins? I think it has something to do with the gray scale being out of adjustment. According to the Sams I am to turn each screen controls clockwise until I see a faint line on the screen with there service switch on, and the color turned off I also turned the CRT bias switch all the way to the left unless I was not able to get a line. My question on this is when it says turn until a line is just hardly visible how intense does it mean? Am I looking for a ghost or a distinct sharp line?
Eventually I would like to learn how to adjust the convergence and purity correctly...

This set does have a service switch, its over by the focus thing.... It's the
one with only 2 positions....

As for the colors.... The Yellow, that is a little green.... It's suppose to be green..
Only new flat screen Sharp tv's have a dedicated yellow.... Not sure how that's going....

For purity adjustments, First turn color off... you are best to leave the service
switch set to normal, full screen. Then with the brightness set somewhat mid point,
move the VHF tuner to a point between stations. You will have to pick a mid-cam
position, not easy to keep that will give you a blank-white screen, no snow....

I don't remember who, maybe RCA, but their service switch was 3 position and one
of the positions was a full white screen with no snow.... Doing it with that line is
just stupid.... they were smokin something when the decided the line was the way to go-

Then turn down the green, and blue screen adjustments. Set the 2 drive adjustments
somewhere mid-point. (or just don't touch them yet.) You should have a red screen....
There are purity rings on the yoke easily visible near the screw clamp. Move one
around and see if the red improves. If it does not easily improve, you may have to move
the yoke forward or back, but try not to do that... I'm not sure if they have only a red
ring, or other colors on that set, so remember where each is, and don't go nuts turning
everything, just move one a 1/4 turn then put it back if it don't change a lot.....
I guess a few of my brain cells for purity on that set are going.... going....

If you get a good solid red, then do the same with green, and blue.... Then re-check.
If you have the Sam's refer to the procedure they have for purity as this set is
off my memory, and it's been more than 20 years.

Once you get pure single color from each gun done one at a time, you can bring
up the red till you see it, then green, then blue, and compare it to a nice
well lit piece of white paper, when you get it right, then you have
basic purity and gray scale set up....

Convergence is next, for this set I would use the tic-tac-toe board, don't bother
with the dots, and just do a overall with the convergence magnets on the tube...
I'm pretty sure the convergence board is not marked, you will
need to refer to the sams for the pots and coils....

.

Re. the low focus CRT, I have never seen one produce good focus, period. No matter which of the 3 taps was used, they always had soft focus. Just the nature of the beast.
Agreed. I never saw one with sharp focus either. The jumper almost
never helps, cant see a difference. When brand new they look a
lot better but in a few years they loose it. A clean & balance
usually helps a lot BUT there is risk & it dont last long as a rule.
I would go with the squirrel & do a set-up on it & use it for learning.
Also keep in mind it will never look "good" in strong lighting.
One other thing to look at is the IF & video amp tubes. They
can test OK but still rob you of the detail & contrast, this looks
a bit washed out to me on top of the other issues.

73 Zeno:smoke:

...

I disagree with username1's instructions on how to set the grayscale. The problem with simply setting the drives at a nominal midpoint and adjusting the screen controls for a good looking blank white raster is that it is possible to have the lowlights off quite a bit when you are done. Use the barely visible line in service mode to get the lowlights neutral, then adjust the drive controls to get good whites on a blank white screen or a regular picture. There can be some interaction, so return to the service position and faint line to recheck the screen controls. This should get you a neutral gray from shadows to highlights.

Anyone notice that the anode cap looks loose in the pic of the back off? Possible reason?

Also, I think I spy a brightener on it.

I was kinda hoping that if he just didn't mess with the drive's yet that he
might just get away with not touching them..... I have found that after a
screen setup, the drives look better when adjusted watching a show in B&W,
as in just turn the color off.... If they need to be done, starting at a mid point
just gives him a range up or down... Good starting point for someone who has
possibly not done this before.... Anyway, there was a good point made,
this is a good set to do some learning on since doing all those alignments
could be a good learning experience.... That's what I did with my Toshiba....
I did get a nice picture, good color, just not sharp like a small screen should
have gotten....

old-tv-nut: If you got insight in the type of setup with his purity rings you
might wanna pipe in on that too, I just don't recall fully what he might
have there.... If you got the Sam's follow it....

No brightner.... Can't see hv lead, it's blocked by the conv. board. They
have a good clip and full cover.

Anyway joseph this will be a good set to learn on, it is well made, has lots
of adjustments, almost each stage has a single tube, there are transistor
stages, I think as mentioned IF stages are I think transistorized, as is with
the first color and osc, I'm pretty sure the demod's and finals are tube....?


.

Thete is no brightner on it, if you ate talking about the cap on the tube it was removed when the set was powered up on a variac. I need to post since pictures of the set now. I might pay a picture of the color bars when i get hone from school. ..
Also, I did not mess with the drives at all yet. Just the screen controls, the bias switch, and the service switch. That's everything I have touched. Tonight, i am going to check out the purity and see if that needs work, then i will do the gray scale adjustments and go from there.

On the service switch collapse to line, and tweak screens procedure I go for a viewing brightness level in a VERY dimly lit room. I turn up the red first then add enough green to get a yellow line then enough blue to get white. If the blacks look tinted afterwards I dial down the prominent color or dial up the missing color. If the whites look tinted after tweak the drives.
The more ya do it the better of a feel ya get. And some sets color demods make a slight tint of some type improve apparent color accuracy.

So i just tested the CRT and it tested pretty good, or so I think so. Here are the results Green 750,Blue 825, Red 900 all of this on a scale from 0-1000
I checked the purity and it wasnt too bad so I will leave it alone for now. The static cinvergence is WAY WAY off. When i put the grid pattern on i could see tge red shiftedto the right a LOT, the blue was shifted up a little bit too. I will work on that tonight. I think that is part of the reason the picture seemed so horrible last night.

Hi Mr. Daniel,
I usually do this--I set customer color control to zero. Then, tint control to halfway. Contrast at zero, and brightness at half.
Evaluate what the issue is--is there too much red or green in the dark parts of the pic? or are the whites tinted?
Use drive controls to set shading of high-contrast components, after making shit sure that the background levels are set so that a low brightness scene has zero amount of color bias..it should be blackish grey after you're done...and the whites shall be white as possible after touching up the drives.
Convergence is next.

I got the color setup batter, I also figured out the purity and convergence. I could not get the screen to converge towards the top of the screen, but I assume that has something to do with the dynamic convergence...
I still have one major problem. The brightness is extraordinarily weak despite the fact that the CRT tests pretty good... At halfway up on the brightness control I get no picture. I have to turn it almost all the way up. I was also having problems with the picture washing out. Any ideas on what this could be?

On the plus side, I am not getting pretty good color, I got the purity and static convergence done. The set has been running now about 6 hours now with no drift or anything so it seems to be pretty stable for the time being... The focus problems I was having are now mostly gone since I setup the static convergence. Before I did the convergence if a white title came on the screen it would be so blurry I couldn't read it at all, and there would a ghost if you will on different sides for different colors... When I put on a crosshatch pattern it became even more pronounced...

You can cheat the brightness with the bias switch BUT you
may be just covering a dog turd with leaves. I would measure
the CRT voltages at abt 2/3 bright & cont. then compare with
sams. The set does lack snap in the video & you are getting
your setup lines so may be a video amp prob. I am missing
this manual so if you can post the CRT end it would help us.

When you get to the convergance remember to go back & forth to
the center every few steps. Ignore the sides when doing the
center. & it will never be perfect ! You want it not noticable
at normal distance & an active pix.

73 Zeno:smoke:

The bias switch is already all the way over, I will post the sams tonight and check the CRT voltage this evening.

A quick check on your video drive problem: check the video output tube then the electrolytic cap in the cathode circuit of that tube. your CRT may be good, but a low drive signal to the cathodes can make it look sick.

Quick update
tonight I worked through the dynamic and static convergence and i was able to get it pretty good exvept for the upper left center. I also got the purity better. The picture still has way too much contrast and not enough brightness, but I got the gray scale pretty much spot on too.
After looking at the chassis closely I think I will be able to get at most of the caps so I might replace a few and spot check a couple resistors. I also wanna take a look at the filter caps at the front of the chassis and clean the tuner just for posterity...

Ya know, the picture really is worlds better now from when it was when i first received it...
Tommrow I will take a look at this sub-brightness control I just found. I will also see about replacing a couple tubes that have a high failure rate and ones that are suspected of being bad...

When I pull the chassis should I bother replacing any of those maroon drops? I am gonna try and get at most of the electrolytics but I am not certan about them... I am really leaning towards just replacing them while I am in there since I would really like this set to work for a long time...

In my opinion, if you want this set to last a long time, and remain functional, you should
not replace any capacitors unless you have tracked down a problem directly to one.

I went through a number of parts changes on this set in an attempt to get a better
picture, I also changed video amplifier transistors, caps, and a few in the color
circuits.... Parts that with tv repair knowledge I thought might be effecting picture
quality, I did not get any improvement, my tv looked just like yours does....

It's kinda like some portacolor sets, there just gunna get so good and that's it....
It is kinda a shame, they did a really nice job designing it, it's well laid out, nice
circuitry, etc. Maybe it needs more of a going through on the video amplifier circuits
than I did, but I would hate to see you waste a lot of time, money, and possibly even
install lower quality replacement parts than are in it now, and get a less reliable,
and possibly poorer performing tv than you have now....

The best thing you could do in the way of improving picture quality would be to test the
video amplifier for it's frequency response using equipment you most likely do not own...
I have wondered if the video amp circuit had poor response, or if its some
place else....

.

Ya probably don't have an old school eye type cap checker. If you did I'd say to test all the maroon drops and lytics in the video stages. Maroon drops virtually never short (the failure mode that makes more things fail), but older drops have been known to go openish or to drift in capacitance value to the point of making circuit performance rather poor to outright bad. Sets that have PCBs I have no issues with replacing the drops in any stages that seem deficient in performance. On a CTC-15 clone set replacing the drops on the video/color board yielded a rather noticeable improvement in performance (it made me wish I'd done so earlier).

All right, so I guess I will not replace those film caps, but I am going to replace the axial electrolytic caps that are in there. When I say relaibale I mean that in another 30 years if I just plugged it in it would work with out much fuss.... I know that is highly unlikely, but I highly doubt those old electrolytic caps in the set will be very good in 2045 :p those electrolytic caps in this set would be 76 years old by then! I do know how to solder, and I am much more conformable on PC boards than I am with point to point wiring since I have quite a bit more experience with it...
The set does have very good picture now, but there is just not enough brightness... I will probably get around to looking at it later this weekend...

Brightness issues should always start with voltage checks of the pins on the CRT (assuming its good of course). the bias of the CRT (K to G1) the screen grids (G2) and the HV pretty much dictate the brightness. oh and it would not hurt to confirm the filament voltage as well.

...

Just a small minor update, I have the set going pretty good and reliably now. I did the convergence a while ago, but it looks like the red has drifted a bit so I will redo that and then button the set back up and leave it how it is. If I can ever remember, I will upload a copy of the sams...

I have a set very close in relation to this one. I haven't powered it on in several years, but I recall it worked alright last time I messed with it. I vividly remember using it during the analog broadcast days. It used to get a very strong and clear signal from WISN 12 in Milwaukee just off the internal rabbit ears.