An NE612 is normally configured as a mixer/oscillator for a DC rx. But watch what will happen if input pin 1 is earthed via a 10 K resistor. The local oscillator will appear at output pins  4 & 5.

So the same chip can act as both as an RX converter and as a TX vfo to drive a buffer to a pa !

An idea for a very simple qrp transciever.

Schematic: