1929
1931

1930

1930 Bell Ten Line Intercom
1930 Bell Ten Line Intercom
Western Electric
Kellogg 925
Kellogg 925
Kellogg Switchboard and Supply
Kellogg 9917
Kellogg 9917
Kellogg Switchboard and Supply
Stromberg-Carlson 1211
Stromberg-Carlson 1211
Stromberg-Carlson
Stromberg-Carlson 1212
Stromberg-Carlson 1212
Stromberg-Carlson
WE 201 Spacesaver
WE 201 Spacesaver
Western Electric
WE 202
WE 202
Western Electric
WE 202 Imperial
WE 202 Imperial
Western Electric
WE 653 Hotel Phone
WE 653 Hotel Phone
Western Electric
WE E5 208 Key Set
WE E5 208 Key Set
Western Electric
Western Electric 505C Cordless Oak Switchboard
Western Electric 505C Cordless Oak Switchboard
Western Electric
Anti-sidetone circuit developed
Anti-sidetone circuit developed
PDF: AT&T Annual Report, 1930
AT&T Annual Report, 1930
Ad: Submarine cable
Submarine cable
Photo: Western Electric Hawthorne Works
Western Electric Hawthorne Works
Video: Phone Pioneers Talk Telephone
Phone Pioneers Talk Telephone
ITT gives Pope Piux XI a gold phone
ITT gives Pope Piux XI a gold phone
PDF: Ericsson 1930 catalog
Ericsson 1930 catalog
Ad: Telephone vs. Airplane
Telephone vs. Airplane
Diagram: AT&T World Radio Telephone Chart
AT&T World Radio Telephone Chart
PDF: Telephone Buildings Of The Bell System
Telephone Buildings Of The Bell System