Abstract: A radar system with improved display brightness in high ambient lighting conditions and with simplified deflection and video amplifiers. The incoming radar return signals are digitized and stored in shift registers with the timing to write the data into the shift registers dependent upon the radar range setting. After the digitized radar return signals have been read into the shift registers, they are read out to the display in a constant time period independent of the range setting. The radar system may be used at closer ranges than was previously possible.

Abstract: A marine radar system having a constant brightness display presentation upon all range settings and with independent switched power supplies for both the MTR and indicator units. The switching frequencies of the power supplies are independent from each other and those of the data clocks and PRF with the switching frequencies of the power supplies being intermediate those of the data clocks and PRF. Means is provided for switching the bandwidth of the system in accordance with the range setting. A digital STC circuit and a North stabilization device are also provided.

Abstract: An energy seal for microwave oven apparatus having a first energy responsive structure disposed adjacent to a first energy propagation path commencing at the peripheral gap between the oven access opening and door assembly walls. A second structure responsive to the oven operating frequency is disposed adjacent to the output end of a second energy propagation path communicating with said first path. In one embodiment a conductive frame trim member forms a second choke-type structure together with underlying door assembly components of a nonconductive plastic material. The energy seal structures may also incorporate a slotted wall arrangement of the type disclosed in U.S. Pat. No. 3,767,884 to Osepchuk et al, issued Oct. 23, 1973.