Automotive Fuse Monitor (CB26299E)

We found this simple car fuse monitor circuit in a William Sheets. The LED lights up when the fuse blows.

Polarity protector (CB23770E)
This relay circuit protects against accidental inversion of input polarity. The circuit was...
Precision Square Generator (CB6361E)
This 80's National Semiconductor circuit uses an era integrated circuit and symmetrical 5V power...
RF Amplifier (CB21658E)
This circuit was obtained from Popular Electronics from March 1967. The transistor used is from...