Circular Trace Research Articles

Microwave Distance Meter “Telemeter OG-1”

The telemeter OG-1 is an electronic distance measurement instrument developed at the Technical University of Warsaw in 1962. A brief description of the instrument is given and a block diagram and photographs are included. Distance measurement is achieved by phase comparison at a modulation frequency of 15 Mc/s; related frequencies are used to determine coarse distances. The carrier frequency is variable over the range 8,900 to 9,500 Mc/s. The system employs a master and a response station that are not identical. A cathode ray tube with a superimposed scale is used for distance readout, and forward and reverse readings appear simultaneously as breaks in a circular trace. The standard error of measurement is stated as ± (3 cm + 5 ppm).

Astigmatism in Cathode Ray Tubes

A new method of observation of astigmatism in cathode ray tubes precisely within ±5 volts is described. Here, a pulsating circular trace is made to appear on the fluorescent screen of the tube. The peak cathode current is first fixed with the normal raster, followed by switching over to the pulsating circular trace. The variation of the focus voltage now causes a very sensitive and significant change in the definition of the circumferencial trace width along the XX' and YY' axes which in turn gives a measure of this parameter. A brief description of the electronic circuits along with the outline of operation is also given.

Ultra-High Frequency Beam Analyzer

This paper describes a method for presenting on a fluorescent screen the time varying velocity and density modulation of an electron beam, modulated at a frequency of 3000 Mc, as it emerges from the cavities of a klystron, the wave guide in a traveling wave tube, or similar structures. In order to deflect an electron beam at this frequency, each pair of the usual deflection plates is replaced by a two-wire transmission line, resonant at the beam modulating frequency. Under proper phase conditions a circular trace is obtained, where one complete revolution of the beam corresponds to exactly one complete cycle of events on the beam at the point of its deflection. Since electrons having different velocities will be deflected differently, a complete velocity and density picture of the beam at a given point of interest is obtained. This is demonstrated by observing the bunching action in the drift region of a velocity modulated electron beam.