What is the purpose of the Signal Strength Display?
Doppler signals of very low strength are not accepted or processed by the instrument. This feature
assists in rejection of environmental noise and vibration. Use the display to evaluate signal strength in
your application. Strong signals will increase in percentage to a maximum of 100% or greater.
Does the PDFM 5.0 require periodic recalibration?
No. PDFM 5.0 calibration does not drift over time. The solid state sensor has no moving parts to wear
and affect calibration. The Doppler flow technique generates an ultrasonic signal proportional to the
velocity of flow. All Greyline timing/counting circuits use crystal-controlled frequency references to
eliminate any drift in the processing circuitry.
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PDFM 5.0 Portable Doppler Flow Meter
