1. Use the rolling tube testing settings chart
2. Set all of the levers to the center position
2.5 Move the SET LINE dial clockwise to turn on the unit and stop when the needle points to 50. Switch the short/leakage switch to short
3. Set the Type, Filament, Plate dials to match the tube type.
Note that many tubes have two test combinations
4. Move paddles in the Top column up, the Bottom column down and leave the others in the middle
5. insert the tube in the appropriate tube holder
6. Let the tube warm up.
7. Press down the short adjust line lever to the test position. Does the needle display move into the GOOD area? If so the tube is good. If the short light comes on or the needle points to the BAD side, the tube is bad.
8. Move the short/leakage switch into the leakage position and repeat the test.
9. If the tube has two tests, adjust the switches and dials and repeat the tests 3-8