Very compact microphone transmitter, 100 MHz.

Shoud fit on 1 x 1 cm piece of veroboard! ( ex mike. en batt. )

Tuning: basically done by adjusting the ferrite core. To adjust the range bend the coil.

The  BC547 is used as an amplifying varicap. So it is actually drawn right!

The antenna is a piece of wire, use any length, but 1/8 wavelength may work better.
Range achieved in plain view can be 100 meter ++.