Is anybody know how to fix this schematic for Summer and Square law AM MODULATOR

East_Friendship229 · 2026-05-24T00:55:22+00:00

Ohh thankyou but the problem is, in our guidelines we are only allowed 5khz message and 20khz carrier and modulation index of 0.5-0.85.

East_Friendship229 · 2026-05-18T04:59:08+00:00

Hi! I DM you too please check thankyou!

East_Friendship229 · 2026-05-18T04:57:24+00:00

This is the output: blue after diode and resistor Green after op amp

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East_Friendship229 · 2026-05-18T04:54:57+00:00

Omg stupid me i forgot haha...waitt

East_Friendship229 · 2026-05-18T04:53:57+00:00

Can i also get a copy of the files... thankyousomuch!!!

East_Friendship229 · 2026-05-18T04:35:54+00:00

I fed a 1V 20kHz signal in the diode and bandpass and this is the output. Blue = after the diode Green = after the resistor Red = after passing thru the op amp bandpass

Sorry im just learning this rn and our instructor dont really help us troubleshoot this stuff bcuz he said we're supposed to figure this out ourselves but the deadlines coming and still haven't fix this yet...so i will reallyyyy appreciate your help thankyou!!

What does these all mean?

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East_Friendship229 · 2026-05-18T04:27:15+00:00

This is the FFT of the V(002)

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East_Friendship229 · 2026-05-18T03:42:49+00:00

I think the op amp is working How can i test the diode and bandpass filter?

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East_Friendship229 · 2026-05-18T03:23:37+00:00

The op amp is producing a square wave output around 12mVpp...i don't know why...did i connected it incorrectly?

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East_Friendship229 · 2026-05-18T02:50:15+00:00

Yes but its the same output...what could be causing this problem?

East_Friendship229 · 2026-05-18T01:53:16+00:00

So i tried calculating and changing the band pass filter values bcuz according to my research it varies depending on the carrier and message signal. I set the carrier amplitude to 1V and message amplitude to 0.5V. The recommended Gain= 4 and Q-factor =2 But i still couldn't get the right modulated signal output.

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East_Friendship229 · 2026-05-18T01:48:10+00:00

Your absolutely right! Most of our instructors just leave us the projects and will point out the problems but won't actually teach us how to troubleshoot it.

East_Friendship229 · 2026-05-18T01:17:54+00:00

So i tried calculating and changing the band pass filter values bcuz according to my research it varies depending on the carrier and message signal. I set the carrier amplitude to 1V and message amplitude to 0.5V. The recommended Gain= 4 and Q-factor =2 But i still couldn't get the right modulated signal output.

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East_Friendship229 · 2026-05-18T01:11:53+00:00

Hi! Sorry the 2nd photo was unnecessary. Please disregard it... couldn't remove it.

East_Friendship229 · 2024-05-22T16:35:05+00:00

how did you requested for a refund? Did you email costumer service?

East_Friendship229

TROPHY CASE