Got a globe O1A tube for a 1920s battery set that is weak? Here's what you can do: "rejuvenate" the tube!
Here's the procedure:
1. Make sure there are no shorts.
2. Hook up the two big pins (filament) to your DC variable power supply.
3. Crank up the voltage to 12 Volts. Ordinarily an O1A runs at 5 Volts however, giving it 12 Volts makes it glow brightly like a light bulb. Do this for 5 minutes.
4. After those 5 minutes, reduce the filament voltage to 5 Volts. What I do is "cook" the tube overnight.
5. Check the O1A the next morning and you will have a good usable tube. Check it on your tube checker, you will be pleased.
*Note: Don't check the tube immediately after applying the 12 Volts. You will get no emission reading at all! The tube must "cook" for at least four to five hours at 5 Volts first.
SPARK members have decades of experience restoring and breathing new life in to antique radios. Here are some of the tips and tricks they have learned over the years.
The information provided in these articles are the opinion of the member and are not guaranteed. Results may vary. If you have questions, please contact us via our "Contact" page.
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