Ready to begin on my roundie
 

Im ready to begin on my roundie, RCA2000 come over to my house today, to bring over the CRT with major cateract problems, and it was nice meeting him. hes a great guy. he also gave me a board with parts to fix my CTC-167, but thats off topic (please dont yell at me mods. lol).

So far, almost all of the bonding degrated, and you can only see the center spot of the CRT. i took off the mailing tape, and no heatgun at all, i peeled off the glass and cleaned it up. the center wasnt sticking all the well either.

jack(rca2000) told me that the tube tests emission like brand new. but he mentioned one of the colors, i think the red was a little weak, but still very strong. Hell, i dont like much red anyway.

the center of the screen, the bonding glue felt like the material they make clear hoses out of or something! it wasnt sticky anymore, and didnt leave any residue behind. it just came off, now I have to clean up the glass.


It says in the service info that jack gave me, that you cannot interchange fjp22 with fbp22. I have no idea what my set had, since the base was broken off that had the number. the one I got now is a FJP22. its an admiral, with the yoke and stuff still attached.

question for jack: Can I still use the yoke and convergence magnet thats on this tube in my zenith? my zenith looks to be missing the purity rings according to the service info. Another thing I noticed, was one of the convergence magnets on the convergence yoke looks a little angled, other than the rest of them. maybe thats what they ment by not interchangeable. I dunno. :scratch2:

Mike, I've noticed on my sets that the mounting band that goes around the front of the crt is different between the fbp and fjp tubes.

One of the bands has tabs that slightly fold over the front of the crt in the four corners. Generally, i've noticed this particular setup used on fbp tubes. When you tighten up the band, those front tabs will hold the safety glass securely in place on the tube.

Seems the fjp band does not have these tabs to hold the safety glass since it's held to the front of the tube with the glue.

I am not sure whether or not all brands of sets did this. The majority of my roundies are RCA or RCA clones... and those are the ones i notice have or dont have the tabs. I have a couple of Zeniths, but, never removed the toobs from them. I am not home right now... if I was, I'd take a pic of what I am speaking of to show you.

If you can find the tabs I am speaking of, that might let you know what the set had in it. Hope that helps.

well, i looked, both tubes are the same, they both are FJP22s. but the admiral mounting band ISNT the same, so i will have to change the mounting bands, and put the degousser on this tube. I found some stickers on the tube covered in dust, i cleaned them off to find the tube type, and date code.


Get this one: The tube that was bad, thats currently in teh set, and im pulling out: Has a date code of '63 odd. the set was made in what, 66 or 67?

it was either a overstock of older tubes that zenith put in there, or a service shop put an older stock tube in there. that explaines why it went to air. its older than the chassus.

i just loooove how zenith made this set, I have to pull the tuners, and wires, and all kinds of crap before I can pull the chassis, and you cant even get to the front tuner and bezel screws hardly at all. Crappy design on thier part. but, I have to unmount the front metal, and pull it out the cabnet so I can put the new tube on the mount and stick the front metal mount back into the TV and rebolt it. PAIN. but oh well.

anyway, back to the point. I got the new tube looking like you just walked with it out of a service shop in the 60's it looks brand new, not an inch of dust on it. you can eat off the tube now.

so, im going to put the new tube in and stuff. I dont have a test pattern generator, so I need advice on convergence.

Yeah, when I first got that 29jc20Q, it was quite evident that removing the chassis was going to be a major job! All I can say is thank God for that screen under the cabinet!!!!!

yea, but that doesnt help when changing the tube! lol.


I wonder, which would be easier. pulling this chassis or pulling moms car motor :scratch2:

Mike, Good luck with your set. Those Zeniths are pretty tough! I see in an earlier post you wondered if you could use the yoke that was already on the Admiral tube? I'm pretty sure you can't. You sould be able to use the purity stuff tho.

The purity and blue lateral magnets were universal. I would not try to use the Admiral yoke. The Zenith yokes have two adjustments (at least mine does) that look like fishing line. I have not seen that on any other round yokes. For test patterns, I got a crosshatch, color bars and an indian head and made up a VCD. Unfortunately, the VCD is all I have left of it after my computer crashed after the big Christmas power failure.

i coulda recovered your data. im good with that stuff you know.

i got all my data back off of a broken RAID 0

i noticed the fishing line. i thought they were used to pull the yoke. oops. oh well

what did they do?

I got the picture tube changed out, and that was a pain in the monkey nut.


But, i let it warm up. and...... WE HAVE A RASTER!!!!!! unrestored chassis.

very insufficiant vertical height, and convergence, purity, all that jaz is messed.

the sound doesnt work either, the only thing working is a severly messed up raster. but, it needs a total recap, so thats to be expected. but however, its usually the other way around. got sound no pic, but me, its the opposite. So, that means the most important parts of the TV are still working.

but, i let it run for a bit. and I saw some magic smoke start comming from the tuner. :cry:

hmm. still more work to go. I never got to teh restoration of the chassis yet, but its doing good so far.

The fishin line is how you adjust the rings for centering and purity. They are designed to only go so far, so, dont attempt pulling them past their stops.

Magic smoke from the tuner? That bites! Hopefully it will only be a Black Beauty that's gone south.

nah, the magic smoke was comming from the degausser.

i pulled of the degausser, and bypassed it. it went from a raster down to a line. so, there is evident trouble in teh vertical circuit. The vertical pulse you can still hear loud and clear, but oh well.

Anyway, that motherbucker almost killed me. something is wrong with the grounding, because I came close to the front metal bezal, and got a nice big 10 foot tossing shock while on. something aint right.

Always make sure a CRT grounding spring is installed, connected to the CRT outer graphite coating, and it is grounded to the chassis...or the CRT mounting hardware can charge up to the HV voltage.

i found the problem. The HV went excessive when there was no vertical, and I replaced a cap in the osc section, and cleaned out the yoke and reseated the connections, brought the vertical back to life. most of the set has been recapped already! I know the orange caps arnt stock. :no:


I now have a full raster, and the tuner is dead. Why is it not the IF sections?
well because you know how you change channels right? duh. lol.

if you try your hardest, and if you hold the knob steady between two channels, (its like a sweet spot). you will get snow on the screen, and static sound. which means the IF is working, but if you put it on a channel, nothing. no sound or picture. but clean raster. even with cable or antenna hooked up.


im assuming the mixer/osc is working hence the static and the snow on the screen, but the RF amp tube is not working. but, I dunno. it may be just needing a good cleaning.

but, im getting a little farther in the restoration. The IF and sweep circuits along with the sound is working.

I cannot get the purity right no matter what I do, its a good clean spot from the center to the right of teh screen, they look normal.

the left is wacked out. red is blue, blue is green, and green is mixed. its hard to explain, like a magnet near the tube or something. The internal degausser is shot, so I used my soldering gun, and it still wont clear up. the centering rings hardly make a difference, and I have them placed between grid 3 and 4 according to the manual. I dunno. :scratch2:

The orange caps may be original. Zenith used those for a long time. As far as purity, pull the yoke back toward the base of the CRT then adjust the purity rings so that the red spot is in the center of the screen. Push the yoke towards the front of the set until the red fills the screen. Of course you should degauss it first the best you can.
Steve

yea i know, thats what I did. the spot got a little bigger when I pushed it back to the bell, but it didnt cover the whole area.

the service manual says to pull it back but-up against the convergence yoke WITHOUT turning the yoke, just pull it back. I did that. I set the rings where the spot was near teh center, I push the yoke back up to the bell, and the spot got bigger, and its red all the way from the center to the right of the screen. but its still blue on the left.

oh well. I dont have a degusser. the big black thermister on mine just smokes.

Sounds like your tuner is dirty. If it's the turret type, I take out that whole assembly and clean EVERYTHING in there well. i don't recommend it, but you theoretically can soak the tunner in something like simple green. Gotta wash with clean water and make sure it's really dry prior to power, or *poof*

TV tunner 'cleaner' is evil stuf. it gums up, attracts dirt, so they sprayed more and more in there, and it never does anything real anyway.
BTW, the diff between regular and 'color' was that 'color' was scented!

I find once you get all the crap out, buff up the springs with an eraser or such, and form them out a it to make better contact, the turret type tunners work nicely. Switch types, you just clean and pray :(

I fixed the tuner, i cleaned the whole thing out. all the connections were all gumed up and nasty.

after this. I got one thing to day

ITS ALIVE!!!!! I HAVE GREAT SOUND AND NOT SO GREAT PICTURE!!!!

i have it on cspan. I absolutly CANNOT get teh convergence to work whatsoever.

the dynamic controls take very little effect. Also, I had to use the slugs on the convergence yoke to get it to line up perfect in the center, but I can't get the blue to line up :no:

and I absolutly cannot get the purity right. I think the CRT is magnetized and my degausser is not working. my soldering gun kinda works, but not really.

Also, does anyone have any 6KT8s they can send me? this set has 2, and one of them with open filiment.

i had no pic or sound. just raster. So, i took the 6KT8 out of the color osc circuit, and put it in the AGC/sync/sound circuit. and now, I have a watchable picture and good sound, but no color, because I dont have the 6kt8 for the 3.58mhz osc stage.

I will post pictures ASAP. i need batteries

Convergence might need some caps or rectifiers changed on it's board. Might be best not to worry bout convergence at this point. You probably still need lytics and other caps on the main chassis. That could end up changing any convergence set up you do now... so you'd have to do it all over again once you go thru the chassis really good.

Using the soldering gun for degaussing has it's limitations. I've degaussed the same way, but, usually takes me a good while to get it "acceptable". One of these days i'll think to buy a coil. They're not that expensive... I just never seem to think about it at the right time.

Oh yeah Mike... just remembered... you might try turning the set 90 degrees. In my garage, purity looks like crap when I have the set turned one way, but gets much better if i turn it some. You may or may not get the same affect... but it's worth a try.

lol. the set is currently facing north/south. the pix tube bell is facing the north, the front is facing south.

Anyway, thats what I was tought when doing convergence. I do the same with projo TVs.

there is no color, I need a 6KT8. mine has a toasted filiment.

the chassis is working perfect. I dont know about the color yet.


vertical, horizontal, sync, everything is locked on and perfect.

cant say so much for the tuner. the only thing I can get right now is cspan. YUCK.

the fine tuning gear that sticks into the tuner to turn the slug on the rotator shaft is broken, so I cant fine tune it. :cry:

the VHF pilot lite is also out. so I guess i can pick them up at ratshack for a dime a dozen.

the UHF one still works. i guess it was never used much. :banana:

please dont point the finger at me and laugh too hard now :cry:


but im stuck here, and cant advance any farther till i get a 6KT8.

right now, there is no color as the color circuits arnt operating, but the picture in person looks much worse than it does on camera, you cant see the purity problem on the camera. Its a B&W picture, but it sure dont look like it. :cry: :cry:

Here is the picts

Mike,

Why is your only choice of channel C-SPAN? That sucks!

While you're waiting to get a 6KT8, you need to do some house keeping in there. I'm seeing lots of dust. That yoke is looking pretty nasty. In some cases, many problems are fixed by cleaning the chassis. I usually get old make-up brushes from girl friends. They work great for gently getting the dust out in conjunction with a vaccuum cleaner hose. I wouldnt recommend a shop vac... that could suck up something you might want to keep. An old Electrolux or something of the sort is good.

When I first got my Curtis Mathes, it was really dusty in there. Wouldn't put a picture on the screen to save it's life. After dusting everything off, it started working. Have had the same experiences with old radio chassis. Considering that Zenith chassis have all of those test points and terminal solder points on the top side of the chassis, lots of dust can effect your picture.

I realize this doesn't fix your color or convergence issues, but, a good cleaning job would be a good idea.

Here's another idea for your convergence... if you're not getting enough movement on the screen as you slide the magnets back and forth on the neck, slide the little magnet stick out all the way, turn it around 180 degrees, and put it back in. That might make a difference for you. I've had to do that before with good results.

By the way... what's the front of the set look like? I don't recall you posting a pic of it yet.

Mike:

Your convergence is so far off you may not get purity. The static convergence looks pretty far off so I wouldn't do anything yet with dynamic. Make sure that the coils and blue lateral magnet are in the proper locations. If you can not get one or another color to move enough in the center of the screen pull the magnet (the entire white plastic thing) out of the convergence coil and reverse it 180 degrees and put it back in. Sometimes this will help.
Steve

Mike:
here are soime test patterns for color and convergence:

http://bs.cyty.com/menschen/e-etzold...t/testbild.htm

download the JPEGs and burn them on a CD and insert it into a DVD player. With the grid pattern (Gittertestbild) you can adjust convergence and with the red screen-JPEG (Roter Bildschirm...) you can easily adjust purity.
The JPEGs will fit in NTSC too, perhaps you might have a black bar on the left or right side.

one problem. its not english. i cant read foreign languages for crap.

BTW I turned the blue lateral magnet all the way around, it didnt make a difference.

ive had those white pull magnets all the way out and in.


I had to use those to get the bottom to converge. but no where else did. :scratch2:

BTW, I do have a pic of the front of the set. its in another thread which you may delete now.

I cant get channel 3 because the fine tune gear is broken. :cry:

i dont know where to get a 6KT8, i was hoping you may have one :thmbsp:

Mike:

Just go to his site and click on the highlighted links and you will get the test patterns. A working knowledge of the German language is not necessary.

i got the test patterns, but the DVD player I have wont show slide shows. it says invalid disc and spits it back out. stupid new-fangled technology. lol.

it only plays DVDs. wont play CDs or others. it will play music CDs without a problem, will NOT play video CDs or picture CDs

it doesnt have an RF jack either. so its crappy.

Anyway I rotate those sticks on the yoke at 180 and it fixed the convergence! but still, the purity is screwed. it needs degaussed. if anyone knows how to rig a modern degausser coil and circuit to an old TV let me know.

it all pulled nicely in the center. I redid the dynamics, and i got the bottom and center to perfectly converge, but the top and the extreme right wont converge. If i try to converge those, it throws the rest off.

pic of it now.


just note, the color circuits are NOT operating, its in black and white, but it looks color because of purity.

Perfect convergence is not always easy to achieve. In most cases, you will not achieve "perfect" convergence. Like you said, you adjust for one side, and it throws off another side. It's a real pain in the butt! :sigh:

Sometimes you must go thru all of the steps 2 or 3 times to get more improvement. I usually end up doing it several times before I reach a point that I feel is acceptable.

At least, you've improved it greatly since yesterday. :thmbsp:

Also, take note of the temperature of your alignment tools after taking them out of the coil. If you happen to notice that the tip is unusually warm after removing it from the coil, that particular coil could have a short.

clearer shot, but white balance screwed up on camera.

there are only 3 coils. the rest are pots.

i never adjusted the coil part yet, i dont have those tools.

Speaking of alignment tools, anyone have a preference to brand or place to buy? My ancient (30 years!) Rat Shacks are worn to a nub. Thanks

Anthony

OH NO!!!!!!!!!!!!!!!!!!!!!!

i tried to turn one of the coils with a flathead, and it crumbled the feret core slug all to peices!! NO!!!

Are the degauss coils around the face of the tube ok? If they are use them to degauss the tube. You should be able to umplug them from the chassis and apply 120volts ac to them directly. I would use a variac so the voltage could be lowered to the coils and they do not shut off all at once. The thermister works by directing ac to the coils when cold then as it heats up it usually acts as a short so no current flows in the coils. If they are in series with the coils the resistance increases as they get hot and current doesn't flow through the coils.
I usually start by degaussing the set, then I get the static center convergence as close as possible, set the purity, repeat if necessary, then I do the dynamic convergence. Oh yeah repeat as necessary. It doesn't always come together the first time, but each time will get easier. It is also a good idea if you have the sams to follow the dynamic convergence instructions in the sequence they are given. Just turning the controls at random may make it harder to converge.

problem: one of the termistors is gone, so the other thermistor I guess continues to run, because the set when it runs, the thermistor will start smoking.

If you can find a junk TV with a coil for horizontal hold, that makes a really good durable adjustment tool for convergence circuit coils. I use one salvaged from a Sampo b/w tv. If there is still a piece of the core inside the convergence coil this may be enough to work if you use the hex head tool to turn it...if it is totally destroyed just salvage another ferrite core from a junk coil.

Once you degauss the set you usually don't need to re-degauss it unless it is moved...radio shack bulk tape eraser works good.

The core is still in there, but when you try to turn it, it seized and it will start to chip some more. it was turning, but I think I turned it a tad too far.