I'm designing AM modulation and demodulation circuits. The AM modulation works fine but when I connected it to the demodulator (I'm using envelope detection) the modulating signal changed to the original message.
Amplitude modulation circuit design:
The modulation output the first one from the top is the carrier. The second one is the message. The third one is the modulation output.
When the envelope circuit is connected, this happens:
The third one from the top is the modulation output. The fourth one is the demodulation output.
AM modulation and demodulation circuit design: