SELF

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S.B. Karavashkin and O.N. Karavashkina

2.2. Description of experimental device

To check the above effect, we used the air-core transformer with three one-layer windings having 470 turns of wire each, winded in series without step one upon another on the round former whose diameter was 50 mm and length 100 mm. The direction of all windings was the same. Between the windings we interleaved the insulation with = 0,08 mm. We chose it so thin because of necessity, the secondary windings to be as possible close in the inductance.

As a primary winding we used the middle winding C₁ . The power was supplied to it from the oscillator of standard signals 3 - 51/1   (see Fig. 5).

Fig. 5. Electric circuit of experiment with the air-core transformer having two secondary windings: C₁ denotes the primary winding, C₂'  is the interior secondary winding, and  C₂''   is the exterior secondary winding

We detected the phase of induced emf with the help of oscillograph, by way of comparison of related shifts of curves on the screen, with unchanged for all windings external starting of oscillograph.

The target of experiment was:

- to study the swings of induced emfs at the interior (U₂₁) and exterior (U₂₂) secondary windings, dependently on the frequency of current in the primary winding and voltage across the primary winding;

- to study the difference of phases between the voltage impressed on the primary winding, and emf induced in the interior secondary winding (₂₁), dependently on the frequency of current in the primary winding and voltage across the primary winding;

- to study the difference of phases between the induced emfs in the exterior and interior secondary windings  () as a dependence on the frequency of current in the primary winding and voltage across the primary winding.

We conducted this study at the range 20 Hz - 200 kHz; the output voltage of oscillator was 5 Ohm; the input impedance of intermediate amplifier was no less than 1 MOhm; the voltage across the primary winding has been permanently controlled and maintained constant on all the range of frequencies.