2. Experiments to determine the electrodynamic induction
In the previous part of this work we have presented the most General approach to non-classical subject — electrodynamic induction (EDI). Here we consider the sensor with which it is possible to successfully fix and conduct on this basis several experiments.
The sensor is a modified version of the indicator of the second magnetic field, which repeats its work, but added a few elements for further research: R12 — variable resistance for external sensitivity adjustment, SW1 is the switch that can connect or disconnect the coil L1, XS2 connector, connects external antenna (Fig. 3).
Repeat the composition of the components and some new nuances in the design and configuration of the sensor.
Coil L1 constitutes the armor of ferrite core with an outside diameter of 22-26 mm, consisting of two halves (cups), in the midst of which is inserted into the coil bobbin. This frame is wound with 100 turns of copper wire of diameter 0.1-0.15 mm in the varnish insulation. To enhance the sensitivity of the sensor, between the two halves of his core need to make a gap of about 0.1-0.5 mm. the Maximum sensitivity of the sensor, when the coil L1 is achieved at the optimum clearance between the cups of the core.
For a list of other elements of the scheme:
- DA1 — dual operational amplifier LM358. Changing to other OU is not allowed;
- DA2 — level meter signal KA2284;
- ..VD5 VD1 — LEDs blue or red glow on 1.5-3V;
- C1..C3 are ceramic capacitors with a tolerance of 10%;
- ..R1 R11 resistors on 0.065-0.125 W with a tolerance of 5%;
- R12 — variable resistor that needs to be taken out to the outside of the housing;
- SW1 — any small switch that also needs to be taken out to the outside;
- XS2 — any external socket; it is important that he approached the plug, which podpisatsja antenna — piece of wire of length 0.5 m.
First, a trimmer resistor R9 is the dynamic range of the sensor. We need to ensure that if there is no signal at the input either led is not lit, and at the maximum signal — shone all 5 LEDs (VD1-VD5). The signal can be taken from coils of the second magnetic field, or by touch, electrified ebonite rod (see below for experiments).
Trimming resistor R2 should be in the middle position, but if desired it can be used to shift the midpoint than is governed by the steepness of the threshold. Resistor R4 exhibited a range of sensitivity adjustment at your discretion. It is important that at maximum sensitivity, the led VD1 began to glow.
For the experiments, we need a sensor SN1, which is described above, and the ebony wand. In extreme cases, instead, it will fit plastic pen or comb, but the effects will be less effective. In all three experiments will need to electrify a stick and carry it past the sensor.
Experiment 1 (figure 4a). The key SW1 is open, the antenna connector XS2 is not connected. Hold the wand near the coil L1. The faster we do it the brighter the glow the first led VD1 or — the more LEDs lit in the line VD1-VD5. Moreover, the sensor does not respond to the electric field itself, but only change. If the outcome of the assumption that dE/dt gives rise to not only the first but also the second magnetic field, it becomes clear reaction of the sensor.
Experiment 2 (figure 4b). The key SW1 is open, the antenna AN1 is connected to the connector XS2; it is a piece of copper wire of length 0.5 m. hold the Stick near the antenna and also as in the first experiment nablyudaem that the faster we do it the better you respond to the sensor. Here also, the sensor only responds to the change in the electric field. In this experiment, we can assume that the response to dE/dt is due to the inertia of the current in the coil L1, therefore, to eliminate this uncertainty will be holding the third experience.
Experiment 3 (figure 4c). The key SW1 is closed (coil L1 in the experience not involved), the antenna AN1 is connected to the connector XS2. Now in the scheme (Fig. 3) remains of the chains which would react only on the time variation of the input parameters, the reaction may be only on the absolute values. But here we are seeing the same effects — responding to field changes and the speed of such change. In fact, in the presentation sticks to the sensor, the antenna AN1 appears induced charge, which is eventually absorbed by the combinations R1-R5. While this charge is not dissipated, the sensor responds to the absolute value of the potential on the antenna.