Hickok 600A Tube Repair, Test and Failed attempt at calibration.

Hickok 600a tube tester - repair, test and failed attempt at calibration.

[@user-em8rg3io2r]

A few comments....as you discovered you are on the octal socket, and the pin numbers start at 1 starting from the right side of the locating key and progress counter-clockwise around the socket to pin 8. Google "Hickok 600a calibration" and find Daniel Shoo's version 4 procedure dated 2006. When using a modern (high impedance) DMM, you need to add various shunt resistors across the meter leads to simulate an old analog 1000 ohms/volt analog meter. The values for each reading are in the procedure. I'm attempting to calibrate my 600a as well.....

[@Almostdone0]

Its funny you brought up Daniel Shoo's calibration procedure, I came across it last night. It is much more in depth than the one I had. Good luck on the calibration, I will probably run through mine next week.

[@stephaniewilley2224]

With my vintage projects, tube are the second I test. The first tests are capacitors.

[@Almostdone0]

I really don't have a good way right now making sure the caps are good, I end up just replacing all of them.

[@timmoritz4925]

Insert the tube after you have set the appropriate switches or you may damage the tube and/or the tester. It would be worth your while to obtain a copy of the operation manual and read it. If you set the english dial to the chart then you read tube condition using the red/green scale. Mutual conductance numbers have no meaning at that point. If you want mutual conductance you set the english dial to the appropriate red dot, not what is on the chart. You counted the socket pins going in the wrong direction but it works out the same for 2 and 7. For the voltage test, you are supposed to be changing the filament voltage knob, not the filament pin setting knob. For an accurate reading set the line voltage first. Hope all this helps.