View Single Post
  #4  
Old 05-02-2018, 10:42 AM
N2IXK's Avatar
N2IXK N2IXK is offline
Technohippie
 
Join Date: Apr 2011
Location: Sittin' on the "Group W" bench...
Posts: 799
About the only tubes that used the 11 pin base were photomultipliers like the 931A type used in the B&K TV analysts. They were pretty common on industrial relays, allowing 3 SPDT contact sets, and 2 pins for the coil.

The 11 Pin plug/socket were also pretty commonly used for connecting external power supply units to vintage ham transceivers. Like the HP-23 supplies used with the Heathkit SB-line.

Last edited by N2IXK; 05-02-2018 at 10:45 AM.
Reply With Quote