This circuit was found in a1980s Motorola documentation. The integrated circuit is from that time. The frequency depends on the crystal.
This circuit was found in a Texas Instruments documentation from the 1980s. The circuit monitors...
This circuit was obtained from a Popular Electronics of 1994. The magazine no longer exists in its...
The load current can be adjusted up to about 1 A. The transistor can be TIP32 or TIP42. The...