Neon lamp NL1 replacement

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NL1 would be a tag identifying a neon lamp on a schematic. It is not a part number. If it had wire leads look carefully at the base, there may be molded in a number 2!

The resistor value for an NE-2 can safely start at 100,000 ohms and then if it is not bright enough reduce it.

The lamps maximum power should be 1/12 watt. If you know the voltage feeding it and allow for a 60 volt lamp drop you can calculate the minimum resistance. So a maximum current of .001 amp, but for longer life half that or less.
 
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Not sure it's a standard neon bulb.
 

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NL1 is fed from a frequency controlled oscillator, not directly from the mains.
There should be 220v DC on one side and about 80v on the other.
There is a fuse, F5 100mA that is prone to blow as the supply components do. Check for dry joints and open circuit R709. If C413 dries out there will be no drive to the current stop transistor.
If the neon is not physically damaged/broken glass etc, it is likely to be OK.


Cunning way to work but very good.
 
It's been a while since I posted an update. I have reflowed the solder on the power supply and did a full recap of the turntable. Unfortunately I still haven't got the right voltages. What's next? Should I unsolder the transistors in the power supply to check if they're still ok? I have measured the diodes in circuit and they appear to be working. Any thoughts?
 
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