| 摘要 |
1,240,909. Pulse width discriminators. FERNSEH G.m.b.H. 7 May, 1969 [11 May, 1968], No. 23380/69. Heading H3P. In a pulse width discriminator the input pulse (at 1) allows a capacitor 11 to charge to produce an output having an amplitude proportional to the pulse width. This output is applied to a threshold device 13 to provide an output when the voltage exceeds a value corresponding to a minimum pulse duration. A second capacitor 16 is discharged by 15 during the presence of this output and charges when the output ceases, the capacitor voltage being fed to a further threshold device 18 followed by an inverter 19. The time constants and the threshold levels are so chosen that the period during which the second capacitor voltage remains below the threshold after the cessation of the output of the first, is equal to the delay before the first threshold is exceeded so that output and input pulses are of equal length. As shown, the output of the threshold circuits 12 and 17 are shaped by Schmitt triggers 13 and 18. Circuit 14 is a further inverter. |
