Ultrasonic piezoelectric transducer S3469 1.8A0D18CL DATA SHEET Main technical specifications Transducer type: Nominal frequency: Nominal echo pulse duration: Nominal relative band width: Nominal sensitivity: Piezoelement diameter: Nominal echo pulse delay in protector: Nominal piezoelement capacity: Connector type: Operation temperature range: Dimensions: Weight: Contact straight beam single 1.8 MHz 2 µs 95 % -40 dB 18 mm 0.08 µs 3500 ± 50 pF LEMO 00.250 from -20 to +50 ◦ C 24×27×23 mm 40 g Measurement conditions and used equipment Excitation: Rectangular pulse with amplitude 20 V and duration 277.777777777778 ns, equal to half-period of nominal frequency oscillations. Amplifier with 0.01-15 MHz bandwidth and 400 Ω input impedance. Effective noise level, normalized to the amplifier input level, is less than 20 µV. Damping resistor: 100 Ω (connected in parallel to the transducer). Single LEMO-LEMO with wave resistance 50 Ω and 1.2 m length. Calibration block: Calibration block CB002-2 from a set of ultrasonic samples of thickness and ultrasonic wave velocity, SN004. Calibration certificate 0930220 of 17.02.2020. Longitudinal wave velocity 5918 m/s, thickness 50 mm (dimensions 230×120×50 mm). Measurement results Spectral amplitude, rel. units Backwall echo pulse for 50 mm thickness and its spectrum

Reverberation-noise characteristics (RNC) of the tranducer without acoustic load and DGS diagram for flat bottomed reflectors with area 1, 3 and 10 mm2 The level of 0 dB corresponds to the amplitude of the transducer excitation pulse. Calculated parameters and acceptance results Parameter Work frequency (Mean of border spectrum frequencies) , MHz Echo pulse duration (at -20 dB level from maximum) , µs Relative spectrum bandwidth (at -6 dB level) , % Sensitivity (bottom echo pulse and excitation pulse amplitudes’ ratio), dB Sensitivity margin above the RNC in the time interval 2 - 50 µs according...