Hickok 6000a limitations

Yes, there most probably is a very lengthy supplement, and I suspect that you can obtain it from:

http://radioera.com

I have a Hickok 800A, and about 15 years ago I obtained the supplement for it (many pages filled with tiny print, so it would not be practical for me to reproduce it for you) from a gentleman by the name of J.W.F. Puett, of Puett Electronics in Dallas, TX. He was and/or is a prominent figure in the antique radio collecting field.

He is no longer in business, but I understand that a few years ago Radio Era Archives (url shown above) purchased Mr. Puett's inventory of literature and other items.

The supplement I have, btw, is identified as being for Hickok Models 533A, 600A, and 605A, but I have never had a problem using the settings it lists on my 800A. So keep in mind that a supplement useable with the 6000a may be identified as being for other models. The people at the link I provided may be able to advise further on that.
Regards,
-- Al

The mutual conductance (micromhos) reading is the minimum reading for a "good" tube. A reading less than that indicates a "weak" tube.

Note that to read micromhos directly you do NOT set the shunt dial to what is listed in the chart. The chart setting is for reading on the "good/replace" scale on the meter. To read on the micromhos scale on the meter, you set the shunt dial to one of the three red dots that are on it, corresponding to which of the three micromhos scales you want to use.

You'll find the following video of interest, although it looks like he is using the tester incorrectly relative to what I said in the previous paragraph about the shunt setting:

http://www.youtube.com/watch?v=OVMnKIM4LEc

Also, note that the 6000A does not provide sockets for testing of early tube types:

http://www.vacuumtubes.com/6000.html

Regards,
-- Al

Yes, you're mostly right about the mutual conductance numbers, Jim. Thanks for catching that -- I haven't used mine in a while either! But according to my 800A literature it is not the average of a new tube, it is the number corresponding to an "average tube":

New tubes typically read higher than the mutual conductance average reading listed in the mutual conductance column of the roll chart. A weak tube will read lower, and a bad tube will cause a very low meter reading or no meter reading at all

And yes, the guy in the video did not do the gas test correctly. On my 800A, which apparently has somewhat different nomenclature than the 6000A, the procedure I was given is to set the English ("Shunt") dial to the 3000 red dot; increase the bias setting; push P5 ("Gas1") and while holding it down adjust bias for 100 on the meter (which is 2 small divisions up from 0 on the 3000 scale); while holding down P5 ("Gas1") then press P6 ("Gas2"). If the meter goes up significantly (past 600) the tube is gassy.

Thanks again,
-- Al