Tunable infrared/ultraviolet laser
Tunable parametric amplifier
Tunable quadrature phase shifter
Tuned circuit and system therefor
Tuned radio frequency amplifier with back to back varactor...
Tuned radio frequency cathode follower
Tuning multiport amplifiers
Two channel read amplifier
Two stage microwave class e power amplifier
Two-port wideband bipolar transistor amplifiers
Two-stage ultrasonic traveling wave device
Two-wire millivolt to milliampere signal converter
Uhf low noise amplifier
Uhf rf amplifier and agc system
Ultra high frequency amplifiers
Ultra short wave apparatus
Ultra short wave system
Ultra-high frequency coaxial line amplifier
Ultra-high frequency device
Utilizing vacuum tubes in computer audio circuitry