This amplifier was found in Burr-Brown documentation from the 90's. The gain can be programmed by resistor Rg as per the table given in the diagram. The power supply must be symmetrical.
This single transistor radio without a power supply was found in documentation from the 1960s. The...
T1 and T2 can be BC557 and T3 a TIP32 for lamps up to 3 A. The supply is made by voltage of 12 V...
This circuit is from the time of the tubes, being indicated to operate with transmitters turning off...