This battery charger circuit was found in the August 1970 issue of Radio Electronics magazine. The circuit uses 4 transistors. Q1 must be provided with a good heat sink.
This circuit was found in a 1967 Raytheon manual. The transistors are from the time. Equivalent modern...
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
The circuit presented generates short pulses. This configuration was found in a publication from...