This is the circuit of a modified Heathkit kit. The circuit was found in a Radio Electronics from December 1965. The author of the circuit included improvements to the original circuit.
Found in ancient American documentation, this circuit uses some components from the time, such as...
In the figure we have the way to compensate an operational amplifier. The circuit is valid for...
With this circuit, it is possible to excite a white LED or another type of high brightness with...