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SamGibson
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I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit in onlinethis answer by Andy aka to a previous question and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit online and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit in this answer by Andy aka to a previous question and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

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I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit onlineonline and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit online and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit online and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”

Source Link

Help understanding amplitude modulation circuit

I’m fairly new to electronics / electrical engineering, and I’ve been reading about amplitude modulation because I find it really intriguing.

I found the following AM modulator circuit online and tried it out (Carrier is V2, Message Signal is V1). It works great in practice, but I don’t really understand how it works or why it’s capable of modulating the signal.

Circuit

LTSpice Simulation Results

In particular, I’m confused about:

  • How this circuit actually modulates the carrier with the input (message) signal
  • Which part of the circuit causes the carrier amplitude to vary
  • Why the peak-to-peak of the modulated signal is 1.25V instead of the messages 2.5V

I have a rough theoretical understanding that AM means changing the amplitude of a high-frequency carrier according to a lower-frequency signal, but I can’t quite connect that idea to what’s happening inside this circuit.

A simple, step-by-step explanation of the signal flow would be really helpful. Time-domain intuition would be especially appreciated, since I’m still learning how to think about these circuits.

Thanks a lot, I’m enjoying learning this stuff and would love to understand it more deeply instead of just knowing that it “works.”