This paper is devoted to analysis of the modern achievements in energy loss problem for piezoceramic resonators. New experimental technique together with computing permits us to plot many resonators' parameters: admittance, impedance, phase angles, and power components etc. The author's opinion why mechanical quality under resonance is different from that under anti-resonance is given. The reason lies in clamped capacity and electromechanical coupling factor's value. The better electromechanical coupling, the stronger capacity clamping, and the higher its influence on anti-resonant frequency and quality. It is also established that considerable nonlinearity of admittance in constant voltage regime is caused by instantaneous power level.

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