Bargraph tachometer (CB7378E)

This analog tachometer was found in Radio Electronics from the 90s. The components used can still be found with some ease.

| Clique na imagem para ampliar |

Self-disconnecting battery charger (CB4975E)
This 12V battery charging circuit automatically shuts off at the end of the charge. The disconnect...
Flying Saucer Sound (CB16274E)
We do not know exactly what sound a flying saucer makes, or if it makes a sound! But this is not...
Regenerative receiver (CB22273E)
This simple 1 transistor circuit was found in an American documentation from the 60's. The...