SELF

12

S.B. Karavashkin and O.N. Karavashkina

To measure the received signal amplitude, we also used a principle of the maximal amplification of signal. For it, between the receiver and oscillograph we inserted an additional amplifier. True, if the amplitude was measured on the oscillograph screen, it was impossible to diminish the error completely, as in case of the phase measurement (and this essentially reflected on the results of the measurement). But allowing the base experiment and mutual corroboration of the results of the amplitudes and phases measurement, the high error satisfied the task enough.

The wave propagation velocity was calculated between all the neighbouring experimental points as

where r is the distance between two next locations of the radiator, where the phase delay _d was measured.

A special matter we gave to the radiator – receiver parallelism, to avoid the distortion of the result in measuring the amplitude and phase.

Finally, taking into account that in the course of experiment we studied the relative characteristics, we took as the initial reference point of the phase  _d its value at the minimal distance between the radiator and receiver equal to 75 mm. We measured the distance between the ends of trumpets.