Medium impedance stage (CB20563E)

We found this circuit in an English publication from 1963. The circuit uses germanium transistors of the time.

Wideband Amplifier (CB24241E)
This circuit was suggested by Texas Instruments in the January 1973 issue of Radio Electronics magazine....
Unijunction transistor sequential timer (CB21400E)
This circuit was found in Motorola documentation from 1968. Transistors can be modern equivalents, just...
Breakout board for DC motor reversal (CB23714E)
To invert the rotation of a motor by changing the levels of an Arduino output or another...