Electron compasses

Introduced: September 1968

Full Title

Full titles differ between systems:

IPC:

Compasses; Devices for ascertaining true or magnetic north for navigation or surveying purposes > Magnetic compasses > Electromagnetic compasses > Electron compasses

CPC:

Compasses; Devices for ascertaining true or magnetic north for navigation or surveying purposes (using gyroscopic effect G01C19/00) > Magnetic compasses > Electromagnetic compasses (with north seeking magnetic elements and having electric pick-offs G01C17/26) > Electron compasses

No child classifications to compare. This is a leaf node in both IPC and CPC.