Based on the well-known LM3914, this circuit was found in an old American documentation. Trimpots adjust the scale limits.
This simple transistorized radio was found in a Japanese magazine from 1960. The phone must be...
This circuit counts from 1 to 10 or 0 to 9 using as indicators common LEDs. The circuit can be...
Found on Popular Electronics from 1969, this circuit can be implemented with components that are...