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 operational amplifier can be of any type in this circuit, found in a 1974 publication. The...
July 2017 - Texas Instruments' new 8-channel digital switches for I2C applications can be found at...
This circuit was originally designed to maintain the temperature of a brooder at 41º C. However,...