MK484 Radio Circuit Stage 1

In the first stage of the radio circuit, I am using the MK484 IC in a slightly unconventional way from the documentation because it works much better. The signal feeds the input of this IC through a 47 pF ceramic disc capacitor. I chose resistor Rp to be 15 kΩ because it provided the optimum amount of voltage to the IC when powering the circuit with a 9 V battery. The 100 nF capacitor is essential and value is extremely critical for the medium wave (MW) band coverage. The output of this IC, which contains the audio frequency (AF) component, passes through a 1 µF capacitor, which provides decoupling between the stages.

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