K7000 static, but no neck glow after shorting.

So you have good B+ and the flyback is working.

Heater path from flyback to CRT socket is detailed in the pic I posted above. There are no caps.
Set meter to AC, black probe on big heat sink, red probe on point C. Then move onto D which is the same as J. You already proved continuity on this trace.

If you have another working monitor, check heater voltage at the CRT socket so you can see if your meter has any reliability when measuring this voltage.
 
So you have good B+ and the flyback is working.

Heater path from flyback to CRT socket is detailed in the pic I posted above. There are no caps.
Set meter to AC, black probe on big heat sink, red probe on point C. Then move onto D which is the same as J. You already proved continuity on this trace.

If you have another working monitor, check heater voltage at the CRT socket so you can see if your meter has any reliability when measuring this voltage.

Whoops missed this. C, d, and j are 0

Edit- yeah nevermind I set that to DC. Trying again.
 
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So you have good B+ and the flyback is working.

Heater path from flyback to CRT socket is detailed in the pic I posted above. There are no caps.
Set meter to AC, black probe on big heat sink, red probe on point C. Then move onto D which is the same as J. You already proved continuity on this trace.

If you have another working monitor, check heater voltage at the CRT socket so you can see if your meter has any reliability when measuring this voltage.

Hey sorry so I've traced the path ac. starting at A it's 3.5v ac all the way to the heater pin.
 
You need to make sure the tube heater is intact (the jumper wire replacing R213 raises concerns) . Remove the neckboard and measure the resistance across pin 9 and 10. It must be a very low resistance (1-2 ohm). Use this pic to locate the heater pins (the two H):

B10-277.jpg

And if you can, swap the chassis with a known working one.

The flyback winding that generates the heater voltage is these two pins. Desolder them so they're loose and not touching the pads and check for continuity across them or shorts with other flyback pins. Unfortunately the pads have eyelets so they're harder to desolder.

FBTheater.jpg
 
You need to make sure the tube heater is intact (the jumper wire replacing R213 raises concerns) . Remove the neckboard and measure the resistance across pin 9 and 10. It must be a very low resistance (1-2 ohm). Use this pic to locate the heater pins (the two H):

View attachment 862660

And if you can, swap the chassis with a known working one.

The flyback winding that generates the heater voltage is these two pins. Desolder them so they're loose and not touching the pads and check for continuity across them or shorts with other flyback pins. Unfortunately the pads have eyelets so they're harder to desolder.

View attachment 862659

Checking resistance now. 3.5v is low right?
 
You need to make sure the tube heater is intact (the jumper wire replacing R213 raises concerns) . Remove the neckboard and measure the resistance across pin 9 and 10. It must be a very low resistance (1-2 ohm). Use this pic to locate the heater pins (the two H):

View attachment 862660

And if you can, swap the chassis with a known working one.

The flyback winding that generates the heater voltage is these two pins. Desolder them so they're loose and not touching the pads and check for continuity across them or shorts with other flyback pins. Unfortunately the pads have eyelets so they're harder to desolder.

View attachment 862659

Nevermind getting 0 resistance across those pins :/.
 
0 ohm means the heater is good. Is that what you're reading? Infinite resistance, OL (overload) or whatever your meter displays when the probe are not touching anything would mean that the heater filament is open and the tube is to be tossed.

If you raise the G2/screen voltage on the flyback, do you see any raster?
 
0 ohm means the heater is good. Is that what you're reading? Infinite resistance, OL (overload) or whatever your meter displays when the probe are not touching anything would mean that the heater filament is open and the tube is to be tossed.

If you raise the G2/screen voltage on the flyback, do you see any raster?

Sorry just seeing this now. It's open as if I'm not touching anything at all. Nothing happens on the screen when I raise the voltage. Also no continuity on the heater pins.
 
Ah, ok. Don't forget to put a resistor in R213 when you source a new tube.

ok thanks, which value should that be? I lucked into a dropin replacement that was 20 minutes away from an old sanyo. Going to do that later today probably. As far as the 3.5v off the flyback... do you think that's the flyback itself or something in the line between the power source and the flyback?
 
The value of the resistor depends on the CRT. The value usually found of 0.68 ohm is for RCA and Zenith tubes. Other brands may require a different value.

The reading you got probably depends on the meter not being true rms and/or not supporting the 15KHz frequency. I think the flyback is fine and wouldn't worry.
 
The value of the resistor depends on the CRT. The value usually found of 0.68 ohm is for RCA and Zenith tubes. Other brands may require a different value.

The reading you got probably depends on the meter not being true rms and/or not supporting the 15KHz frequency. I think the flyback is fine and wouldn't worry.

Hmm alrighty Ill do the tube swap later tonight maybe and let you know how it goes. The meter I'm using is a fluke 107. Not quite a 117, but pretty solid
 
The meter I'm using is a fluke 107. Not quite a 117, but pretty solid

FWIW, the Fluke 117 is a "true RMS" meter while the Fluke 107 is not. However, neither of them is capable of accurately measuring a 15kHz AC heater voltage. You'll get *some* kind of reading, but it won't be anything close to accurate.
 
FWIW, the Fluke 117 is a "true RMS" meter while the Fluke 107 is not. However, neither of them is capable of accurately measuring a 15kHz AC heater voltage. You'll get *some* kind of reading, but it won't be anything close to accurate.

Does this mean even at the traces coming off of the flyback?
 
Does this mean even at the traces coming off of the flyback?

It means those meters are incapable of accurately reading a 15kHz AC voltage, no matter where or how you try to measure it. For a CRT heater voltage, you're typically looking for 6.3V AC. Those meters are not able to accurately measure that.
 
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