Fig 1 shows a simple 27MHz transmitter producing a carrier.
(receiver for this circuit HERE)
The 27MHz transmitter PC board
Here is the circuit made by Lucian Papadopol firstname.lastname@example.org
He has created capacitor values by paralleling two values.
This means it produces an unmodulated 27MHz signal and when picked up by a receiver, such as shown in fig 2, the result is a clean, noise-free reception. To increase the output of the transmitter, the 390R resistor is replaced by a 220R. This increases the current from 7mA to 12mA. The resistor could be decreased to 150R for more output.