This basic circuit showing the LM3914 “inside” was published in the October 1980 issue of Radio Electronics magazine. Note that R1 determines the brightness and that the power supply is 9 V.
This 5.1 MHz oscillator was found in a 1980s American documentation. The used operational...
A NOR gate can be improvised using one NAND gate of a 4011 as shown here. The diodes are...
Found in the September 1982 issue of Radio Electronics magazine, this circuit triggers a relay...