We begin with realizing two resonant circuits, the first one of type in series, the second with the elements in parallel, as those design to you on the left of figures 1 and 2.

Fig. 1 - When the ferrite of the circuit come to an agreement and that inner of the receiver radio are near and parallels, the weak people mark them come remarkably reinforce to you and I listen increases of level.

For both circuits coil (L1 is necessary one), wrapped on ferrite nucleus and a variable condenser to air. The coil is come true wrapping 8O coils of enameled thread of branch of the diameter of 0,6 millimeter on one cylindrical ferrite, of diameter. long millimeter and at least 10 cm. The variable condenser to air must have one the maximum ability to 300 pF.
The first experiment, illustrated in figure 1, consists in tuning a small receiver radio on one issuing weak person around to the 800 - 1,000 KHz, with the scope to cancel the most possible action of the CAV, that it would alter the effects introduced from the presence of the come to an agreement circuit and to approach this, most possible, to the receiver, so that the two ferrites, that one of the external resonant circuit and that inner to the apparatus radio, come to find in position parallel. Fact cio' is taken part on variable condenser CV in order to tune the resonant circuit on the same frequency of the issuing receipt, obviously after to have applied, to the free extremity of L1, the conductor of reduction of an antenna to spin and, on finishes them of the variable one, the earth conductor.
II caught up result is following. While it is acted on the hinge of variable the CV, to one sure point one notices to us that the audio increases remarkably of intensity. Like if picked up issuing I' from the receiver had multiplied its power of emission. But we see hour that what has been taken place in theory.
II circuit approached the receiver is of resonant type in series that, to the frequency of resonance, established from the characteristic electrical workers of the L1 coil and variable condenser CV, absorbs the maximum of energy irradiated in the issuing space from the wireless one on which the receiver is tuned. This energy provokes in L1 the sliding of one variable current, that it generates, around the coil, a variable electromagnetic field to radio frequency, which it invests the inner coil of the apparatus radio, starting in this one current that already present sum on that one. In short verification a transfer of energy, which had to the mutual inductance (effect transformer), but favorite from the mutual position of the two coils and from their grip vicinity.
In this case it is used to say positively that the come to an agreement circuit alters deeply, but, a connection between resonant circuits.