| 摘要 |
PURPOSE:To stably sweep the frequency, the amplitude, and the offset with a high precision by adding a D/A converter for amplitude sweep and that for offset sweep. CONSTITUTION:The waveform signal which is outputted from a waveform memory 5 and is converted by a D/A converter 6 is outputted through a multiplier 8 and an adder 10. The multiplier 8 multiplies the output of a D/A converter 7 for amplitude sweep by it to change the amplitude of the waveform. The adder 10 adds it to the output of a D/A converter 9 for offset sweep to add the offset to the waveform signal outputted through the multiplier 8. When the frequency of the output waveform is changed, sweep data in a sweep memory 3 is given to an address generator G20 for a memory 5, and fixed values are given to converters 7 and 9. When the amplitude of the output waveform is changed, data in the memory 3 is given to the converter 7, and fixed values are given to the generator G20 and the converter 9. When the offset is changed, data in the memory 3 is given to the converter 9, and fixed values are given to the generator G20 and the converter 7. |
