Zenith color console 14B9C50

[JohnCT]

Originally Posted by pac.attack76

So I need to remove that fuse? Pin 5 is G1 right?

Yes on both.

When troubleshooting red plating, it's best to avoid running the circuit until the problem is solved, but if you need to run the circuit to make voltage and waveform measurements, then running without the cathode fuse is one way to prevent the plate from dissipating too many watts and weakening it. Removing the plate cap is another, but sometimes the lead drifts back to the tube and arcs.

Pin 5 is the first grid on most typical Zenith outputs like the 6LF6, but if you have a different output (not familiar with your model number), then you can look up the datasheet for the tube on line and identify the first grid.

John

[pac.attack76]

Originally Posted by JohnCT

Yes on both.

When troubleshooting red plating, it's best to avoid running the circuit until the problem is solved, but if you need to run the circuit to make voltage and waveform measurements, then running without the cathode fuse is one way to prevent the plate from dissipating too many watts and weakening it. Removing the plate cap is another, but sometimes the lead drifts back to the tube and arcs.

Pin 5 is the first grid on most typical Zenith outputs like the 6LF6, but if you have a different output (not familiar with your model number), then you can look up the datasheet for the tube on line and identify the first grid.

John

My horizontal out is 6LB6.

[JohnCT]

Originally Posted by pac.attack76

My horizontal out is 6LB6.

Then yes, pin 5 is G1. Should be a large negative voltage on pin 5 to ground - maybe -60 or so.

If that's missing, that's good. Loss of horiz drive is easier to troubleshoot than a secondary load issue.

Is there a schematic on line for your TV?

John

[pac.attack76]

Originally Posted by JohnCT

Then yes, pin 5 is G1. Should be a large negative voltage on pin 5 to ground - maybe -60 or so.

If that's missing, that's good. Loss of horiz drive is easier to troubleshoot than a secondary load issue.

Is there a schematic on line for your TV?

John

No idea. Put on 5 and ground. Got nothing. If I put it on right setting...

[zeno]

If you dont get the neg voltage on pin 5 of the 6LB6 either the
hoz osc is dead (6U10 ) or associated parts, OR the 6LB6 is dead
shorted.
BTW NEVER measure the plate of the 6LB6 OR the damper unless you like
fire trucks. Your meter will go up like a Tesla !
BTW #2 the HV regulator ( 6HS5 or 6HV5 ) must be matched with the
right damper tube. Look for tags on HV box or layout chart. Wrong
pair will work BUT not right & not for long.
Good you are taking it slow....

Zeno

[pac.attack76]

Originally Posted by zeno

If you dont get the neg voltage on pin 5 of the 6LB6 either the
hoz osc is dead (6U10 ) or associated parts, OR the 6LB6 is dead
shorted.
BTW NEVER measure the plate of the 6LB6 OR the damper unless you like
fire trucks. Your meter will go up like a Tesla !
BTW #2 the HV regulator ( 6HS5 or 6HV5 ) must be matched with the
right damper tube. Look for tags on HV box or layout chart. Wrong
pair will work BUT not right & not for long.
Good you are taking it slow....

Zeno

Will a dead tube still light or no?

[Electronic M]

Originally Posted by pac.attack76

Will a dead tube still light or no?

It's absolutely possible for a tube to have a good heater (part that lights) and a dead cathode (signal tubes and CRTs alike get this) or a short. Got a tube tester or know somebody with one?

[pac.attack76]

Originally Posted by Electronic M

It's absolutely possible for a tube to have a good heater (part that lights) and a dead cathode (signal tubes and CRTs alike get this) or a short. Got a tube tester or know somebody with one?

Unfortunately no

[Electronic M]

Originally Posted by pac.attack76

Unfortunately no

You really should if you want to work on tube era sets. The alternative is to buy 2-3 examples of each tube (unless the seller has tested them there's no guarantee that they aren't used duds being sold) that you suspect is bad and try each of them... this is a bad approach on color horizontal sections as the 6LB6 is a $25-50 tube and 3 are more expensive than a basic tube tester.

[pac.attack76]

Originally Posted by Electronic M

You really should if you want to work on tube era sets. The alternative is to buy 2-3 examples of each tube (unless the seller has tested them there's no guarantee that they aren't used duds being sold) that you suspect is bad and try each of them... this is a bad approach on color horizontal sections as the 6LB6 is a $25-50 tube and 3 are more expensive than a basic tube tester.

I'll have to see if I can get one. Never thought I'd really need on but I've acquired more tube sets than expected.

[zeno]

We had good luck with the B&K. Just be sure it has the set-up book
& be modern, @ 1970 + REMEMBER checkers are NOT the final word.
Good tubes can check bad & bad tubes good.

Zeno

[pac.attack76]

Originally Posted by zeno

We had good luck with the B&K. Just be sure it has the set-up book
& be modern, @ 1970 + REMEMBER checkers are NOT the final word.
Good tubes can check bad & bad tubes good.

Zeno

I hear that. I'll see what I can do but not sure I can get one.