We done the BCD to 7 segment conversion in many of the digital circuits. But in all that situation we use the decoder ICs. It is because it is the cheapest and simple solution. But I am thinking about the circuit realization using discrete components. Here in this project I made a fully functional BCD to 7 segment converter circuit which only uses discrete components like transistors, diodes, resistors,... I already made discrete BCD counter and flip flops in my previous projects. Please visit it.If you interested to know more about this circuit. Please visit my Blog. In there I explain it well. Link is given, https://0creativeengineering0.blogspot.com/2019/03/bcd-to-7-segment-display-decoder-using.html Also watch the video.