The circuit in the figure operates at frequencies from 4 to 20 MHz and also uses a common junction FET such as BF244 or BF245. The operating frequency is the key, and the RF shock must have a high reactance at the operating frequency of the circuit. For the indicated range, shocks from 100 uF to 1 mH can be used. The supply voltage range of this circuit can vary between 5 and 15 V when then we will have a typical current consumption of the order of 6 mA.
