Minnesota 13
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No neck glow but HV. Measured the heater voltage looking for 6.3 but it is at 1.5VAC. So do I need a complete replacement flyback?
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you measured at R422, but is it 1 ohm? also make sure all the solder connections are good at the plug header pins and I would resolder the neck socket for added measure.No neck glow but HV. Measured the heater voltage looking for 6.3 but it is at 1.5VAC. So do I need a complete replacement flyback?

What meter are you using to measure the heater voltage? A lot of DMMs can't accurately read the 15khz AC voltage on the heater circuit.
That's right. DMMs are digital sampling devices. You need an analog meter to measure that. Something like this beauty:
EDIT: I'm talking about a Simpson 260. With a mechanical movement and a needle. I'm having network issues and can't upload photos at the moment.
In my experience, cheap $10-$20 analog meters won't cut the mustard here. I personally was never able to get my Rigol digital scope to do it either. I've never used the Simpson, but the only meter I've seen accurately measure heater voltage is a Fluke 87 that I borrowed from @security0001.
My digital meter is true rms.
That's right. It's about the sample rate. For a 15.7 kHz signal, you need a meter capable of at least 31.4 k-samples/second.That's not the point. My Fluke 117 is also "true RMS" and it cannot accurately measure a 15kHz AC voltage.
if you see anything on the screen then the heater is at least doing something. lolI was answering the question to what kind of meter I am using not debating the functionality of a digital meter in measuring high frequency voltage. I thought about measuring the current draw to determine the voltage. The tube heater resistance is spec at 2.5 ohms. The heater winding on the flyback is not open.
As suggested the pins to the tube socket were re-soldered and the tube screen has light. Adjusting the screen pot the tube starts at dark then a full yellow screen to white to the raster bars. I will have to sort out my connections to the the monitor. Thanks for all of the comments.