Military I-177, WWII: this mutual conductance tube tester is easy to operate and reliable.
Unfortunately it cannot test European tubes and requires a socket adapter to test more recent
miniature, subminiature and other tubes.
Military TV-7/U, mid fifties: this can be considered as an updated I-177, capable of testing
almost all U.S. receiving tubes and several low power transmitting and special tubes.
AVO MK IV is known as one of the most complete and reliable vacuum tube characteristic
meter, suitable for laboratory use. It can test thousands of European and U.S. tubes, including
many and many special tubes.
The Chinaglia PVT440 is a combined meter for field service. It includes both an emission tube
tester and a multimeter. Suitable for most of the old European and US tubes.
The Chinaglia PRV410 is a tube emission tester, useful for a quick check of old European and