This circuit was found in a 1967 RCA manual. The transistors are of the time. The adjustment is made to read 7.15 V on the charged battery and the charging current is 3.2 A.
The frequency depends on the coil and is not found in the original documentation but should be...
This is a device for those who need to show that they know how to use digital electronics but have...
Using an operational amplifier with FET, this circuit from a 1977 publication can generate...