A very interesting tube tester from Precise Development Co ... The model 111 is a full function mutual conductance and emission tube tester that tests almost every type of tube a radio or audio collector is likely to need. What I found interesting was that many early tubes are listed on the roll chart ... O1A, 99, 112 and many others not commonly found on most roll charts.

The Precise 111 has ability to test tubes for both emission and mutual conductance. It can use 6 different plate voltages, 3 screen voltages and various signal voltage values, it also has very good gas check and ability to measure filament current. Measuring data is condensed in roll chart. Included is a copy of the manual with interesting sections on using the 111 with a scope to derive curves and testing new [not listed in the roll chart] tubes from data in tube manuals.

The tester is in very nice condition .. working and very clean inside .. roll chart moves freely. Elaborate setup procedure is more like a lab quality tester than a service level tester. Both the 5U4 and 6X4 tubes inside are good .. I did note several original capacitors inside that should be replaced for continued reliability but as noted, the tester seems to be working fine. Other than a little light surface rust on some plated components .. the tester and case are both in nice shape .. even still has the original leather handle. It measures approx 16\" X 14\" X 6\" deep and well packed shipping weight will be 26.5 pounds from zip code 24012.

Free manual & test data downloads: />

.