This nice analog indicator circuit was found in the January 1974 issue of Radio Electronics magazine. The circuit has 8 scales with individual adjustments. The instrument is rated at 50 uA.
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...