The present invention is directed to a new parametric amplifier structure which exhibits a large gain-bandwidth product and low noise characteristics without cryogenic cooling. In addition, higher idler frequencies are attained and which are easily adjustable in resonant frequency. The amplifier includes a stacked pair of uncased varactor diode chips within a waveguide channel, which chips are stacked in a predetermined direction.

[Corresponding to U.S. Patent No. 3, 764,850]

A magnet applies a magnetic field of predetermined intensity and shape to a spent electron beam over an axial distance having a predetermined relationship to the frequency of operation of a utilization device which has extracted energy from the electron beam and at a predetermined axial distance after the beam has left the magnetic field of the utilization device and entered the beam expansion region and beam stabilization region. The stabilizing magnetic field is terminated abruptly before the electron beam enters a collector apparatus.

WINGTIP VORTEX DISSIPATOR FOR AIRCRAFT

NASA Case No. LAR-11645

Canada, Japan, Germany

Address inquiries to:
Langley Research Center
Attn: Patent Counsel

Mail Code: 313

Langley Station

Hampton, VA 23665
U.S.A.

[Corresponding U.S. Patent - Application Pending]

The lift-induced wingtip vortex associated with large jet aircraft has become a major problem to the air traffic controller as well as an unseen hazard to smaller aircraft. In this invention, a means for attenuating this potentially dangerous wingtip vortex is disclosed which consists of a drogue device attached downstream of the wingtip which creates a positive pressure gradient just downstream from the wing. The positive pressure forces a break up of the rotational air flow of the vortex.

VOLTAGE CONTROLLED VARIABLE POWER DIVIDER

NASA Case No. GSC-11659

Canada, Great Britain,
France, Germany, Japan,
Netherlands

Address inquiries to:

Goddard Space Flight Center
Attn: Patent Counsel

Mail Code: 204

Greenbelt, MD 20771
U.S.A.

[Corresponding to U.S. Patent No. 3,769,610]

In the voltage controlled variable power divider of the invention, the total output power equals the input power and both outputs have constant and equal phase. The applied power is split into two channels, each of which contains a variable phase shifter. The channels are combined in a 90-degree hybrid coupler so that the relative amplitude in the hybrid outputs is a function of the phase of the hybrid input signals. The phase shifters are voltage driven in opposition so that constant phase is achieved for all output power division ratios.

Masking selected portions of a ribbon and forming an inter-metallic compounds on the unmasked portions by a controlled diffusion reaction produces a twisted filamentary structure. The masking material prohibits the formation of superconductive material on predetermined areas of the substrate.