Inventor

EMBREE DAVID M

US6 patents

⚠️ This page may combine multiple inventors who share the name “EMBREE DAVID M”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

AT & T BELL LAB

2 patents

US4973922ANov 27, 1990

Voltage controlled variable capacitor and oscillator using it

AT & T BELL LAB33 citations90

US4491691AJan 1, 1985

Electronic tone ringer

AT & T BELL LAB11 citations70

AMERICAN TELEPHONE & TELEGRAPH

2 patents

US4887053ADec 12, 1989

High frequency VLSI oscillator

AMERICAN TELEPHONE & TELEGRAPH7 citations71

US4853655AAug 1, 1989

High frequency CMOS oscillator

AMERICAN TELEPHONE & TELEGRAPH10 citations71

AT & T INFORMATION SYSTEMS INC

1 patent

US4508937AApr 2, 1985

Method and circuitry for encoding telephone ringing signals

AT & T INFORMATION SYSTEMS INC20 citations77

AT & T TECHNOLOGIES INC

1 patent

US4567333AJan 28, 1986

Electronic tone ringer with distinctive signaling circuitry

AT & T TECHNOLOGIES INC9 citations70