Deflection Detector

Repairs to the e.h.t. section of a monitor or a television receiver always carry a certain amount of risk. It makes sense, therefore, particularly for the less ex- perienced technician, to seek a safe way of checking the extra high tension. In all television receivers and monitors, the e.h.t. is generated in the deflection circuits. These circuits operate at about 16 kHz which generates a fairly strong magnetic field via the line transformer. It may be safely assumed that as long as the deflection circuits function cor- rectly, the e.h.t. will also be all right. Ad- mittedly, there is a possibility that a defect high-tension winding may be the culprit. But let"s not be pessimistic .... The proposed circuit enables "wireless" monitoring of the e.h.t. section, since it picks up all signals between about 14 kHz and 45 kHz (and their harmonics) and converts them into audio signals. The frequency of oscillator IC, may be varied with the aid of a potentiometer. The oscillator output is ...