MK484 Radio Circuit Stage 2

In the second stage of the MK484 radio circuit, we are interested in amplifying the audio frequency (AF) signal. In this stage, we can use a general-purpose transistor such as the BC549C for amplification. For the self-biasing configuration, I decided to use a value that may work with a large range of NPN transistors. Providing you pay attention to their terminals, and connect it correctly, it should work! I also had the 2SC9011 to try out and it works fine as well without having to change the biasing.

Again, we decouple this stage with a 1 µF electrolytic capacitor at the input and output, to block any DC component, allowing only AF to pass through.

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