RCA CTC-16XL Suggestions/Tips

[Yamamaya42]

why does it look like you have wax or something on the tip of your HV rect 3ca3.
should not be there, and how did it get there?

[Electronic M]

Originally Posted by Rocket

Thats crazy huge!




Ah! that's awesome to know! I may have to check that out and see how that changes things. But yeah, there is a few spots on that very outer 1-2'' that is lousy. but you can't really tell when tuned into a broadcast and does look great from 10 feet back. its impressive the quality of the picture on these older sets!

Indeed you remember correctly, it does have a tube rectifier. And I am up for helping out that flyback. I did notice the ma's surge over 300 for a very brief moment when the tv is first turned on. How hard is that to do solid state conversion?

I am not sure what I am looking for on the arching/corona. Do I need to do that check when the tv is running? I did notice that there was a static build up on the lead coming from the top of the hv cage. I did attach a few pictures of the flyback as well. I have a hunch that I am going to doing that flyback surgery to remove the rubber and do a silicon coating.

Moving the yoke is for when things are badly out of range...Most procedures have you do the RG horiz and vert lines top and bottom first. I recently did a set where those would barely converge. The controls could barely achieve symmetrical mis-convergence (which consisted of bad mis-convergence over ~2/3 of the screen) moving the convergence yoke a bit got it to where I could converge it perfect to within 1" of the edge.

The SS upgrade consists of unplugging the tube, connecting a HV diode across the solder lugs on the underside of the socket banded end to cathode pin other end to plate pin...If you have a rect tube with an open heater you could put it in the socket for appearance. Putting two SS diodes in series for higher PIV tolerance may be advisable move...IIRC the upper focus voltage on some roundys is partway between 4 and 5KV so a single 5KV PIV rated diode may not have enough headroom. This probably will only knock less than 5mA off of H output cathode current.

In a dim or dark room with the HV cage open look for blue or purple glow inside the HV cage with the set running...The 16 and later RCAs did not make doing this easy with the way they mounted the rect into the lid.

[Rocket]

Originally Posted by Yamamaya42

why does it look like you have wax or something on the tip of your HV rect 3ca3.
should not be there, and how did it get there?

Yeah it does look like wax or something like that, it's always been there since I got this set and I haven't had a set like this before so I had no idea and guessed that it was supposed to be there, maybe as a conductor or something. So I clean that out?

[Rocket]

Originally Posted by Electronic M

Moving the yoke is for when things are badly out of range...Most procedures have you do the RG horiz and vert lines top and bottom first. I recently did a set where those would barely converge. The controls could barely achieve symmetrical mis-convergence (which consisted of bad mis-convergence over ~2/3 of the screen) moving the convergence yoke a bit got it to where I could converge it perfect to within 1" of the edge.

The SS upgrade consists of unplugging the tube, connecting a HV diode across the solder lugs on the underside of the socket banded end to cathode pin other end to plate pin...If you have a rect tube with an open heater you could put it in the socket for appearance. Putting two SS diodes in series for higher PIV tolerance may be advisable move...IIRC the upper focus voltage on some roundys is partway between 4 and 5KV so a single 5KV PIV rated diode may not have enough headroom. This probably will only knock less than 5mA off of H output cathode current.

In a dim or dark room with the HV cage open look for blue or purple glow inside the HV cage with the set running...The 16 and later RCAs did not make doing this easy with the way they mounted the rect into the lid.

Thanks for all the help so far Tom! I sure appreciate it : )

Thats some helpful info on the yoke. This is my first color set I've ever played with. But it's really awesome and I've really enjoyed learning and fixing this set.

The solid state upgrade seems pretty easy to do. I could always clip the heater pins on the tube afterwards? I would like to keep it in for looks.

Yeah I was thinking it would be hard to have that open with the way that tube is mounted, then it just dawned on me that I drilled some holes in the top of the cage, so I should be able to see in there. I will fire up the set for another run this evening before I pull the chassis again and see if I see anything going on in there. Could that wax stuff in the top of the fly where the tube plugs into it cause the corona? And I wonder if having the HV turned down can prevent that, I wonder why the HV was turned down low.

[Yamamaya42]

yes, it should be as clean as you can get it.
it's the connection between the FB and the RECT tube
https://imgur.com/xNgchz5 mine
very clean, save for a slight carbon arc point where i did not have the cage closed far enough

[Yamamaya42]

One thing to note about HV arcing and corona, if its happening BEFORE the HV rect, one tends to hear the 15k osc sound in it , if after, it has a more static type sound.
but this is rather general...

[Rocket]

Originally Posted by Yamamaya42

One thing to note about HV arcing and corona, if its happening BEFORE the HV rect, one tends to hear the 15k osc sound in it , if after, it has a more static type sound.
but this is rather general...

Wow that is a lot cleaner! I will try cleaning that up before my next run this afternoon. Maybe that will clear up the corona.

Thanks for the tip on that : D it's hard to recall now, but I want to say it sounded more like static. I will try to grab a video of it later this afternoon. Perhaps a before and after even.

Any idea if corona is really bad for the fly? I sure hate to ruin it

[Yamamaya42]

https://www.youtube.com/watch?v=BUnPkymnxUw

on this he fixes a flyback and draws a AC arc, though you rally cant hear it fully, you can SORT of hear the 15khz whine when he does.

A DC discharge is mostly after the biggest cap in the TV is charged ( the CRT ) and something someplace is bleeding it off somewhere.

[Rocket]

Originally Posted by Yamamaya42

https://www.youtube.com/watch?v=BUnPkymnxUw

on this he fixes a flyback and draws a AC arc, though you rally cant hear it fully, you can SORT of hear the 15khz whine when he does.

A DC discharge is mostly after the biggest cap in the TV is charged ( the CRT ) and something someplace is bleeding it off somewhere.

Ah! So I got a problem somewhere causing this happen to the flyback, may not be be a problem with the fly then?

[Yamamaya42]

Originally Posted by Rocket

Ah! So I got a problem somewhere causing this happen to the flyback, may not be be a problem with the fly then?

what i mean is, if its an HV AC related problem, and has the 15khz sound, its likely FB arc related. but if its more static crackle, like noise its more likely to be DC related, which could even be a crt grounding issue.

Also with an AC arc you get an ozone smell most of the time.

as he said w/o being able to look inside with it running, its hard to tell what is going on.

[Rocket]

Originally Posted by Yamamaya42

what i mean is, if its an HV AC related problem, and has the 15khz sound, its likely FB arc related. but if its more static crackle, like noise its more likely to be DC related, which could even be a crt grounding issue.

Also with an AC arc you get an ozone smell most of the time.

as he said w/o being able to look inside with it running, its hard to tell what is going on.

Oh I see! Most interesting and cool to know! Thanks for explaining how everything works : ) I sure appreciate it Yamamaya!

I was able to check out that video, he has some cool videos. I'd say I was getting the noise he had when he hooked up the horizontal tube, not the noise when he jumped the Sparks with the screw driver. I do see the difference now.

It's almost dark here, so I am going to fire up the set before long and see what happens

[Rocket]

I may have found it or one of them. Takes about 15 minutes for it to warm up before it starts.

Killed the lights, could not see any arching or light peaking into the holes on the HV cage. Then I saw a decent sized blue arch coming from that big plastic cap of the HV regulator tube behind the HV cage. Got a picture of it even. it seemed a bit loose, so I cleaned up the cap and got it to fit snug. I no longer see the blue arch. I can still hear some hiss, not near as bad. I can't seem to find it or see it. I believe I am smelling that ozone smell, boy it kinda stinks.

I did notice that a 6BK4-C was installed so I tried the RCA 6BK4-B that I happened to have on hand and has the correct base on it. No change on that end, but it does glow a pretty cool green! Never seen a tube glow green before O.o

It's a bit late today for me so I am going to call it a night. Tomorrow I am going to look in the HV cage and take a closer look at that flyback and see if I can see anything, clean up that wax stuff on the top of that fb and see if I can figure a way to run this thing with that cage door open.

un related but interesting as I've been monitoring the current draw and when first turn on and its cold it hits about 320ma for a split second before it settles in around 197-201ma

[Yamamaya42]

Originally Posted by Rocket

I may have found it or one of them. Takes about 15 minutes for it to warm up before it starts.

Killed the lights, could not see any arching or light peaking into the holes on the HV cage. Then I saw a decent sized blue arch coming from that big plastic cap of the HV regulator tube behind the HV cage. Got a picture of it even. it seemed a bit loose, so I cleaned up the cap and got it to fit snug. I no longer see the blue arch. I can still hear some hiss, not near as bad. I can't seem to find it or see it. I believe I am smelling that ozone smell, boy it kinda stinks.

I did notice that a 6BK4-C was installed so I tried the RCA 6BK4-B that I happened to have on hand and has the correct base on it. No change on that end, but it does glow a pretty cool green! Never seen a tube glow green before O.o

It's a bit late today for me so I am going to call it a night. Tomorrow I am going to look in the HV cage and take a closer look at that flyback and see if I can see anything, clean up that wax stuff on the top of that fb and see if I can figure a way to run this thing with that cage door open.

un related but interesting as I've been monitoring the current draw and when first turn on and its cold it hits about 320ma for a split second before it settles in around 197-201ma

6BK4C is a newer version with better voltage rating a radiation protection.
that "green glow" is x-ray radiation NOT SAFE, for long term exposure.

the wax in the top of the FB is a bit disturbing...
cant really understand how it can get in there.

"figure a way to run this thing with that cage door open. "
one COULD drill out the 2 rivets holding the socket assembly at the top, but then you would have to come up with a way to hold it in place with the tube in the correct position in the FB when testing... and WARNING,,,
Running like that is a grater x-ray hazard than peeking at the HV reg...

[Rocket]

Originally Posted by Yamamaya42

6BK4C is a newer version with better voltage rating a radiation protection.
that "green glow" is x-ray radiation NOT SAFE, for long term exposure.

the wax in the top of the FB is a bit disturbing...
cant really understand how it can get in there.

"figure a way to run this thing with that cage door open. "
one COULD drill out the 2 rivets holding the socket assembly at the top, but then you would have to come up with a way to hold it in place with the tube in the correct position in the FB when testing... and WARNING,,,
Running like that is a grater x-ray hazard than peeking at the HV reg...

Well I don't want to be x-rayed too much so I popped the -c version back in.

Took some time this morning to clean all that wax out out of that connector. I am worried about that as well.

Sound seems to be coming from the HV reg cap. It gets better or worse when it's rotated. But has not got as bad since I tightened up the connection. Could I have a bad cable/cap?

[Yamamaya42]

Originally Posted by Rocket

Well I don't want to be x-rayed too much so I popped the -c version back in.

Took some time this morning to clean all that wax out out of that connector. I am worried about that as well.

Sound seems to be coming from the HV reg cap. It gets better or worse when it's rotated. But has not got as bad since I tightened up the connection. Could I have a bad cable/cap?

could be,,,
once they start to get carbon on them, it's hard to stop it.

I lost the cap to my horz output, and had to rig something, not as critical at the reg, they do have caps you can buy, but I'm not sure what size to get.