This section covers the unusual tubes designed by Dr. H. P. Donle. The earlier types were marketed by the Connecticut Telephone and Electric Company and the later types by the Donle-Bristol Corporation.

Donle A

Donle C

Connecticut J-171

Sodion S-11

Sodion S-13

Sodion S-14

Sodion D-21

Donle B6

Donle DA2

Donle DA4

Donle DP71