In the figure we have a simple thermometer with NTC, using an analog current indicator. The adjustment is made in the trimpot and the power is done by batteries.
This low-power circuit for small lamps according to transistors was found in the January 1959...
This dimmer for the 120 V (117 V) network was found in the magazine Electronics Now of August...
This old amplifier uses germanium transistors from the time. The circuit is from a Mullard...