| 摘要 |
PURPOSE:To generate the background noise required for simulation video, by taking the random noise produced as the signal of specified pulse width, taking logical product between the frequency dividing output and the comparison output of the integration output of two oscillators, taking the logical sum for a plurality of outputs and introducing them to CRT. CONSTITUTION:The random noise generated from the noise generator 1 is converted into digital signal via the counter 2 and decoder 3, this digital signal is fed to the monostable multivibrators 4...4<n> and the output signal 13 having specified pulse width can be obtained. Further, the signal 13 is fed to the frequency dividers 5...5<n> to obtain the signal frequency dividing the output signal of specified pulse width. On the other hand, the signal integrating 11 the output signal of the oscillator 9 and the signal integrating 11' the output signal of the oscillator 9' which is asynchronous with the oscillator 9 and has non-ietegral multiple of frequency are compared at the comparison circuit 12, this comparison output signal and each frequency dividing signal are taken for ANDs 6...6<n>, and the output is fed to CRT8 after taking logical sum 7. Accordingly, the background noise of simulation video required can be produced with a simple constitution. |
