and here's my *antique* tube tester...

Since I posted pics of my (newer) EICO machine earlier this evening, I couldn't stop thinking about my *other* tube tester, so here's pics of that one too. :-)

This likely dates from the 1940's, (earlier?) and is model #450 made by the SUPERIOR INSTRUMENTS COMPANY of NY. It is in a nicely made but well worn finger-jointed wooden case w/brass hardware and leather handle, that measures about 14-1/2" x 11-1/2" x 6". It still has its original cloth covered power cord. There are a handful of old paper documents with it, including two seemingly original 'tube number charts' and a 'tube substitution chart' (both on thin cardboard) and an envelope containing several typewritten pages of "OPERATING INSTRUCTIONS" and additional tube number charts bearing the letterhead of a "SOUTHERN AMUSEMENT COMPANY" of Little Rock, Ark, apparently a business that supplied "phonographs -- coin operated devices". I can only guess this tester was, at one time, property of that Amusement Company...??

It would have worked just like the EICO -- you'd set the dials according to the tube number found on the chart, plug the tube in, let it warm up, and read the test results on the meter.