Hickok Model 600/600A/800/800A/533 Tube Tester  
 Quick Reference Instructions by Daniel Schoo from Illinois.

AC LINE ADJUST: Push P7 and adjust the AC line control until the meter pointer is at the LINE mark at the center of the meter face. Check and adjust the setting after inserting each tube for test.

TUBE TEST SWITCH SETUP: Set up the switches before inserting the tube to be tested. Find the number of the tube to be tested in the setup chart. Set the switches as listed in the chart. Start with the filament voltage listed in the FIL. heading and continue with the other settings in order as listed under the SELECTORS heading. FILAMENT, FILAMENT, GRID, PLATE, SCREEN, CATHODE, SUPPRESSOR. Set the BIAS and ENGLISH dials to the settings listed. Always do the SHORT TEST first. Use the 'P' key listed under the PRESS heading to perform the tube test. The number listed under the MUT. COND. heading is the minimum for that tube to be considered operable. This is for reference, normally the GOOD-?-BAD scale is read. Read and follow any special instructions under the NOTATIONS heading.

SHORT TEST: Set up the tester switches as indicated in the tube listing. Slowly rotate the SHORTS switch through positions 1 through 5 and observe the short indicator. A glow indicates a short. A momentary flash when switching from 1 to 2 indicates a high resistance short between the heater and cathode.

MUTUAL CONDUCTANCE: Set up the tester switches and the BIAS and ENGLISH dials to the settings listed in the tube chart. Perform the short test first and stop there if a short is found. Push P4 and read the tube condition on the red and green GOOD-?-BAD scale.

MUTUAL CONDUCTANCE VALUE: To read the mutual conductance directly, set up the tester as usual. Set the ENGLISH dial to one of the orange dots on the scale between 70 and 80, or 80 and 90, or 90 and 100. The dot between 70 and 80 sets up the tester to read directly in Micromhos on the 3000 scale. The other two dots set up the tester for the 6000 and 15000 Micromho scales. Test the tube and use the MUT. COND. value from the chart as the minimum acceptable value.

GAS TEST: Set the ENGLISH dial at 73. Push P5 and hold. Set the BIAS dial to cause the pointer to read 100 on the 3000 micromho scale. Hold P5 and push P6. Gas in the tube will cause the reading to go up on the scale. Movement of less than one division is satisfactory. If the reading cannot be brought down to 100 with the BIAS dial, set the BIAS dial to 100 and perform the GAS TEST.

LIFE TEST: Measure the mutual conductance as usual. Press P4 and adjust the ENGLISH dial until the meter reads 2000 on the 3000 scale. While holding P4 down, reduce the filament voltage one step. For example 12.6 to 10.0 or 6.3 to 5.0. If the reading stays in the green GOOD range of the scale the tube has ample reserve.