The small transmitter shown in the figure can generate signals in the range of 50 MHz to 200 MHz. The power is in the order of a few tens of milliwatts and the power can be made with batteries or battery. The capacitors must be ceramic. The 1 pF capacitor between collector and emitter is for a range of 150 to 200 MHz when then L2 has 2 or 3 turns of wire 26 in a non-core shape of 1 cm in diameter and L1 is formed by 1 or 2 turns of the same wire Linked in L2. For 100 MHz (FM range) L2 has 4 turns of the same wire in the same shape and L1 holds. The antenna, for greater efficiency may be a half-wave dipole as shown in the figure.
