| 摘要 |
measurement technology; nondestructive tests using, for instance, eddy-current method. SUBSTANCE: device has pulse generator, controlled frequency divider, counter, read-only memory unit, digital-to-analog converter, and low- frequency filter. Newly introduced in device are two switching units, inverter unit, and switch. First switching unit functions to switch over address inputs of read-only memory. Each sector of read-only memory unit saves instant-value codes of sine-wave signals for sine-wave half- cycle. Each sector is assigned definite number of sampling points for sine-wave signal period. Second switching unit, inverter unit, and switch are used to recover sine-wave signal by half of its period. Mentioned sampling-code saving method enables equalizing counter operating frequency and sampling frequency. EFFECT: enlarged frequency band of generated signal towards increase in maximal frequency. 2 dwg
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