Good day Guys,
I have a question regarding output signals of a specific stage getting distorted when connecting the next stage. In my scenario, I am working on an AM modulator and demodulator of a 10kHz square wave with a carrier frequency of 850Khz, currently, my Modulation is working and producing a nice modulated signal. Before implementing my demodulator I run my modulated signal through a Gain stage ( Operational Amplifier ) to amplify the modulated because of its low peak values that are influencing the accuracy of the Demodulator. When I send the demodulated signal through the gain stage (without the gain stage output connected to the demodulator) I get a nice amplified signal. However, my problem comes in when I connect my demodulator to the output of the Amplifier stage, the output from the Amplifier stage changes to a very weird looking signal. The modulated, amplified (without demodulator stage connected) and amplified (with demodulator stage connected) can be seen in the figure below,
So my question is why does this distortion happen, and how can it be fixed? I am terribly sorry if it is due to noobies mistake!