Before the era of large-scale integration (LSI) semiconductor circuits, discrete logic circuits using the common diode-transistor logic (DTL) were still necessary and available in a format that was ...

Sometimes, the parts list says it all. 777 transistors, 1223 resistors, 136 LEDs, 455 crimp connectors, 41 protoboards and 500 grams of solder. That’s what went into this transistor logic clock build.

These days, a lot of digital design work involves little more than patching together a few highly integrated blocks. It seems as if everything is VLSI (and CPLD/FPGA). A lot is, but not everything.

The previous article examined the concept of logic gates. They can be made from discrete and active electronic components, although today logic gates are available within integrated circuits. In this ...