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Repairing Vacuum Tube TV?

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James1000

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Hi All

When I turned on my vacuum tube tv last night, one white thin light came across the screen. When I unplugged the tv plugged it back on and turned it on by the on button, the screen didn't turn on and the tv on button light just kept flicking.

What could be possible wrong with my tv.

Best regards James
 

Sounds like the power supply was starting to go bad the first time you turned it on.
When you turned it on a second time, it dropped so it can barely light the 'on' light.
 
what it is? what it is model TV . where it is schematic diagram . Give you more information . from what you write it follows that is thin a line in horizontal.Yes?
 

Make and model number are needed so we can investigate. When you say "vacuum tube TV" so you mean just the screen (CRT) is a vacuum tube or there are several vacuum tubes inside it?

If the line was horizontal and fairly central on the screen it means the field oscillator or output stage has failed. Possibly it is now dragging the power line low and stopping the TV starting altogether. We need to know the model number before a schematic can be found.

Brian.
 

This thread pretty soon will be one year old.

Wonder what happened to the original poster? Decided to ditch the old TV and purchase a brand new LCD one?
 

A thin white line across the screen is normally due to the PCL805/ PCL85 valve or associated circuit. Check the height resistor (normally 1M) which is connected to the boost voltage, which could be open circuit. Any wax type capacitors in the PCL805 circuit could be leaky, which could be the cause of the fault.
 

The thread starter stopped posting after this thread. I also notice obviously wrong guesses, e.g. a TV with "flickering on button" can be expected to use a switched mode power supply and has rarely a vertical deflection tube.

Considering nearly 1 year expired: Thread closed.
 

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