RCA CTC...Something? poor HV output.

[DavGoodlin]

To add to Old Coots' post: there are two brown wires that run on TOP of the PCB between the 6GU7s and the 6GY6s. These carry filament voltage to 6GU7/6GY6 on right side, and due to heat, corrode to green dust where they enter the PCB hole.

[Arcanine]

Originally Posted by DavGoodlin

To add to Old Coots' post: there are two brown wires that run on TOP of the PCB between the 6GU7s and the 6GY6s. These carry filament voltage to 6GU7/6GY6 on right side, and due to heat, corrode to green dust where they enter the PCB hole.

Both of my 6GU7's heaters light up, and it appears the aforementioned connection has seen a reflow already. I tried wiggling them around a little, and nothing changes at all.

I also noticed there is a fair amount of arcing out of the top of plastic cup on top of the fly back box. The wire to anode goes in though there, as well as two others. I'm going to need to see what that's about. I'm sure that'll be worse once I get the HV back up.

The tubes are largely original, almost all RCA. I'm hoping I just have a flat tube. I'll add the 6GU7's to the check list.

[Arcanine]

Something tells me this tube shouldn't be so... crispy...and dark. The camera can't even pick up on just how bad it actually is looks.

This is the 6EL4 tube. It's also RCA original.

[DaveWM]

tube dark from xrays, just means had a lot of use, does not mean bad.

you should 1st try running the set with the CRT plug (the base socket)disconnected, this removes the load of a CRT which may be high due to bad CRT or incorrect bias.
Check HV

if no change, then try disconnect the 6Bk4, this takes the shunt tube out of the circuit, could be a prob if bad or bias is wrong.
check HV

if still no change
Check Horz out voltages, screen and grid
Check Horz out cathode current
Report back findings for whats next.

[Arcanine]

Originally Posted by DaveWM

tube dark from xrays, just means had a lot of use, does not mean bad.

you should 1st try running the set with the CRT plug (the base socket)disconnected, this removes the load of a CRT which may be high due to bad CRT or incorrect bias.
Check HV

if no change, then try disconnect the 6Bk4, this takes the shunt tube out of the circuit, could be a prob if bad or bias is wrong.
check HV

if still no change
Check Horz out voltages, screen and grid
Check Horz out cathode current
Report back findings for whats next.

CRT plug disconnected: 14kv

6BK4 Disconnected CRT plugged in: 14Kv

I'll have to check the other two after my trip to see Jim.

I made sure I had a stonger connection with the probe today, the set is managing 14Kv

[Arcanine]

Would a stone cold dead 1v2 focus rectifier cause the issues the set is suffering from?

I tried to test it today, nothing glows inside, and it is fully dead according to the tester. I can't get anything out of it.

[Arcanine]

It actually had a 2AV2 in the socket. I still can get nothing from it on the tester with the correct filament voltage. It at least glows but does nothing.

I can get the needle to show something with the 3A3 and the other high voltage rectifiers, but this one shows nothing. Not even a little twitch.

I also don't think the socket has been modified at all to make a 2AV2 work.

[zeno]

1) bad focus rectifier gives bad focus !
2) your pix bright, full width, does not bloom.
The hoz osc, out, damper, rectifier, focus rectifier, HV reg
are all good. Your meter is NG, try it on another set.
3) arcing at the HV rect socket usually the cup. Other 2
wires are the filament & wrap around the FBT core.
ALL the wires are at full HV potential. & can arc anywheres.
4) Try a "by the book" grey scale set-up. then turn you attn
to the 6GU7 area of the set. Watch for dried up wires, they
were common even 45 yrs ago.
5) put up a few screen shots that show people & colorful scenes.
A pattern is fine but a real scene shows more.
6) the old pixs looked AWESOME so unless the jug has aged
fast & it happens, you will have a great set.
7) so you have 3 problems. Vert, arc & poor color. You should
get a first generation Sams for this set.

73 Zeno

[StellarTV]

Originally Posted by Arcanine

Something tells me this tube shouldn't be so... crispy...and dark. The camera can't even pick up on just how bad it actually is looks.

This is the 6EL4 tube. It's also RCA original.

HV Regulator tubes use lead-impregnated glass to minimize X-ray emission. They darken with use.