Wow. That looks really nice. Do you know about amplifier circuits? Namely OP AMPS. And negative feedback loops. + and - inputs and single outputs. High input impedance and low output impedance. Basic idea of how you fine tune a radio and how amplifiers are added to it. The basic elements to the radio and amplifier connections. Your amp looks nice. And also the component not only is used for radios, but also used for adding and summing circuits. Audio mixers. This also is a popular gadget in electronics.