Abstract: Digital samples of an HDTV video signal are compressed by determining groups each of three successive samples in the video signal lines, the groups in adjacent lines being offset from one another, and transmitting only a first sample in each group. Each of the second and third samples in each group is compared with magnitudes averaged from three adjacent, transmitted, first samples, one in each of the previous, same, and following video signal lines, to determine a closest match. A 2-bit code representing this closest match is transmitted for each of these second and third samples in each group. The groups, and hence the first samples, are offset from one another in adjacent video signal lines, and the sampling frequency is desirably an odd multiple of half the video signal line frequency to offset the sampled pixels in adjacent video signal lines. The invention provides a high compression ratio, which can be further increased by DPCM encoding of the successive first samples.

Abstract: Electromagnetic emission from a printed circuit board is monitored by energizing the board while it is located adjacent an array of electromagnetic emission measuring probes. The probes are successively addressed and currents induced in the probes are measured at a receiver. A memory map of the electromagnetic emission as a function of board position is generated and is displayed together with the circuit board layout so that regions of high emission level can be identified in the circuit. Each probe of the array is a series connected pair of wire loops, the planes of the loops being perpendicular to each other and to the plane of the array.

Abstract: Electromagnetic emission from a printed circuit board is monitored by energizing the board while it is located adjacent an array of electromagnetic emission measuring probes. The probes are successively addressed and currents induced in the probes are measured at a receiver. A memory map of the electromagnetic emission as a function of board position is generated and is displayed together with the circuit board layout so that regions of high emission level can be identified in the circuit. Each probe of the array is a series connected pair of wire loops, the planes of the loops being perpendicular to each other and to the plane of the array.

Abstract: The invention relates to a matrix wipe generator for television signals. With matrix switching, the television screen is divided into a plurality of blocks, and, if the screen originally contains the picture A, then picture B is switched into the blocks one at a time until all of the blocks, i.e., the whole screen, are filled with the picture B. The novel generator in accordance with the invention provides waveforms which give a Z-axis wipe effect, that is, the B picture appears to come into the screen from behind the A picture in each block.