Donle/Sodion
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