| 摘要 |
PURPOSE:To perform easily and accurately the control of a signal transmission volume and a gain digitally by arranging a resistance attenuator group, which has an attenuation quantity corresponding to the count output of a digital counter, on the signal transmission line. CONSTITUTION:Operation switch 8 can be switched to a one-step mode and a continuous mode, and the first pulse generator 6 or the second pulse generator 7 generates a single pulse or a continuous pulse train according to the operation of the one-step mode or the continuous mode, and generated pulses are inputted to digital counter 4 through OR gate circuit 5. Then, a binary output according to count is given to resistance attenuator group 3. Resistance attunuator group 3 consists of plural resistance attenuators including analogue switches and the attenuation quantity of each attenuator is set according to the binary output of counter 4. By this constitution, a desired-level analogue signal can be obtained easily at output terminal 2. |
