11
Screen picture
Description
Sfreq:
The start frequency of the test sweep.
Efreq:
The end frequency of the test sweep.
Step:
The frequency step interval.
Press
or
to change the place of the flashing cursor, and press
or
to change the value of the number where the cursor flashed. If the
settings are finished, press
to begin the test.
When the test starts, the TEST menu appears on the display:
Screen picture
Description
Freq:
The frequency at which the impedance is currently
being measured.
Zmag:
The impedance magnitude at this frequency.
Zphase:
The phase angle at this frequency.
You can press
to stop the change of the frequency. The impedance and
phase angle at the frequency now is shown on the screen. Press
to
continue the sweep.
When the sweep is finished, the RESONANCE menu will appear:
Screen picture
Description
Freq:
The resonant frequency of the tested transducer.
Zmag:
The impedance of the tested transducer at
resonance.
Zphase:
The resonant phase angle.
This data shows the resonant point of the transducer. This is the point where
the transducer is most effective. Generally this should be within about 5 % of
the echo sounder frequency. Zmag is the impedance measured at the
resonant frequency. This is usually within the range of 20 to 300 ohms,
however the exact ranges are available from the manufacturer. If this value is
very high or very low, then the transducer may be at fault.
MANUAL TEST
Sfreq: 040.0 kHz
Efreq: 060.0 kHz
Step: 000.1 kHz
MANUAL TEST
Freq: 040.1 kHz
Zmag: 0635 Ohm
Zphase: +179 Deg
RESONANCE
Freq: 050.0 kHz
Zmag: 0635 Ohm
Zphase: +179 Deg
