This simple charger was found in a 1980s documentation. The transistor may be the TIP42 with a heat sink. R1 adjusts the load current. The transformer has 1 A of secondary current.
The purpose of this circuit is to extend the range of frequency meters (typically up to 30 MHz) to...
This basic configuration of an astable multivibrator was found in a publication of the year 1968....
The frequency of TTL square signal is divide by 5 with this circuit. Power supply is 5 V and the...