John Larkin wrote on 11/9/2017 8:44 PM:
On Thu, 9 Nov 2017 11:14:39 -0500, bitrex
wrote:

Not exactly a sophisticated piece of test equipment, but lets you eject
bad metal enclosure tubes early:

https://www.dropbox.com/s/m5b4ogl4pqn8tu1/IMG_20171109_110954264.jpg?dl=0

(all the metal tubes in the 1935 table radio passed)

Tube testers came as

Filament test

Emission (basically see some plate current)

Gas (grid current)

Shorts

"Mutual conductance" with real AC signals


There were transistor testers for a while, but they went away.

There are transistor testers on many voltmeters. A six (or maybe more, I
don't have one here to look at) pin socket lets you plug in a transistor of
any configuration (EBC, BEC, etc) and I think the gain is shown. But I have
never used that feature, so I'm not sure I'm remembering it right.

--

Rick C

Viewed the eclipse at Wintercrest Farms,
on the centerline of totality since 1998