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Apologies for the captured image quality but I have a circuit from a communications textbook Fundamentals of Electronic Communication Systems 3rd Edition, by Louis E. Frenzel Jr.

The image below consist of a Commutating SCF (Switching Capacitive Filter) for which I do not understand how it works on conditioning an input signal, like an arbitrary sine wave.

Communicating Switching Capacitive Filter

To help resolve my gap in understanding, I created a circuit in a 2008 Student Edition of National Instruments Multisim 10.1.

Communicating SCF circuit schematic in Multisim 10.1

Except for output, all discrete components, voltage sources, ground points, are placed, connected, with all relevant points of measurement hooked into the three devices all in my software environment

  • Agilent Function Generator (50 Hz = 1/4 of the divided input clock output of 200 Hz)

  • Tektronix Oscilloscope (Time Scaled at 10 ms / division)

    • Decoder Out 0
    • Decoder Out 1
    • Decoder Out 2
    • Decoder Out 3

  • 4 Channel Oscilloscope (Time scaled at 10ms / division)

    • Channel A - Clock (400Hz)
    • Channel B - Reset
    • Channel C - Decoder Input A
    • Channel D - Decoder Input B

Animated Measurements

Problem: All non clock signals are displaying flat lines on both oscilloscope measurement channels

Questions:

  1. How do I set up the controlled one shot for reset functionality, and properly wire the left three pins above the rectangular blocks along side the diamond voltage source.
  2. Would the present resistor value of 2.21kΩ and 4 capacitor values of 6.2μF produce any sort of reasonable result?
Vahe
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    Since you only want to see how the circuit works (not build it), why not simplify things and use ideal switches and voltage sources, instead? For example, in LTspice, I would do something like [this](https://i.stack.imgur.com/C5Srj.png). – a concerned citizen Dec 24 '20 at 20:58
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    Just FYI, the word is **commutating** rather than communicating. – Elliot Alderson Dec 24 '20 at 23:14
  • @Eliliot, thank you so much :-) , my eyes and mind never saw this. I appreciate this so much. When I see something one way for so long I forget there is a completely new world of seeing it. Question wording corrected to reflect appropriate name. – Vahe Dec 24 '20 at 23:20
  • The question remains, however, I would like to request help on how to provide a power on reset pulse (active high or low) Specifically, what circuit element or connection of circuit components should I use? – Vahe Dec 26 '20 at 21:49

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