A #30 ballast tube drops 1.2 volts @ 120 ma. For testing you could replace it with a 10 ohm resistor. Used in Sears 1862 radio.
Here is a list of available ballast tubes from PTOP:
http://www.oldradioparts.com/2a2fl.txt
Norm
:Am looking fo a 30 ballast tube or sub.
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