Motorola suggests this circuit in an 80's documentation. The circuit uses an inverter to produce a higher voltage for 9 V battery charge from a single cell.
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
This circuit was found in a documentation of the 80's having characteristics of high overvoltage given by...
Here we show how a Constant Current Source can be created in the Multisim Blue using a common BJT...