Abstract :
The raster outline produced on a CRT screen by receiver deflection currents and modulation is greatly affected by parameters other than those characterizing the deflection yoke or the tube. Several systems capable of providing independent evaluation of the deflection yoke performance have come into use. Among these are "idealized" sweep arrangements, in which interfering and secondary effects common to receiver chassis have been minimized, systems which display only one of the raster sides at a time, and displays in which the raster outline is gradually developed by the application of complex synchronized waveforms to the winding systems representing the two axes. This paper describes a method and the equipment necessary to produce a raster outline, in the form of a continuous trace, by relatively simple means, using deflection currents of readily duplicable waveforms which permit constant and direct metering. The arrangement requires no external sync or video signal, does not need switching, is free from transients, and displays the entire raster outline plus a horizontal reference axis. The mode of operation is such that only standard picture tubes are required for the display to be evaluated.