SELF

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S.B. Karavashkin and O.N. Karavashkina

4.2. Description of experimental device

To realise the above experimental technique, we have modernised the previous device and inserted a framework shown in Fig. 16 onto the ferromagnetic core.

Fig. 16. The framework with one-layer windings set into each other

We winded onto this framework two one-layer primary windings set into each other, using the wire 0,07 mm, having the number of turns w_a = w_a =1200  each. So the scheme of experimental device took an appearance shown in Fig. 17.

Fig. 17. Experimental device to study EM induction of the elements of primary loops parallel to the single probe

The electric circuit of this device is shown in Fig. 18.

Fig. 18. Electric circuit of the device for studying EM induction of the elements of primary loops parallel to the single probe

In distinct from electric circuit of previous study, the primary windings were fed from a power oscillator of low-frequency oscillations; in this way we were not limited by the only frequency of input current. We could change the phase of feeding of primary windings by the switch S₁ . Besides, we provided the possibility to vary smoothly the amplitude of feeding voltage of the winding c at constant amplitude of feeding at the winding a, using potentiometer R₁ = 120 Ohm . We also introduced some changes into the circuit of measurement. In the circuit shown in Fig. 18, the phase of inductive emf picked off the probe 1 was compared with the voltage phase at the winding a at the screen of oscillograph by way of switching the input of amplifier with the switch S₂ . This allowed us to determine more accurately the phase interrelation between the voltage across the primary winding and induced emf.