FLIR RAYMARINE A98 - Fine-Tuning the Frequency

resolution image that may not be as good at
detecting small sh. Use lower frequencies if you
require a large coverage beneath your vessel or if
you are in deep water.
• Medium frequency — non-CHIRP mode (e.g. 90
kHz) — Produces good detail at most depths, with
moderately wide sonar beam.
• High frequency — non-CHIRP mode (e.g. 160
kHz) — Produces a narrow beam and produce
a high resolution image. They are most useful
in shallower water (up to 1000 ft) and at higher
speeds.
• Low Chirp — CHIRP mode (e.g. 42 to 65 kHz) —
No ne-tuning is not needed as the CHIRP sonar
module will sweep the transducer’s available
frequency range in each ping.
• Med Chirp — CHIRP mode (e.g. 85 to 135 kHz)
— No ne-tuning is not needed as the CHIRP
sonar module will sweep the transducer’s available
frequency range in each ping.
• High Chirp — CHIRP mode (e.g. 130 to 210 kHz)
— No ne-tuning is not needed as the CHIRP
sonar module will sweep the transducer’s available
frequency range in each ping.
With the CHIRP sonar module set to a non-CHIRP
mode the frequency can be ne tuned to adjust the
frequency at which the transducer is transmitting.
The graph below depicts ne-tuning of a CHIRP
broadband sonar frequency (from —50% to +50%).
1. Tuning range
2. Transducer characteristics
3. Operating (center) frequency
Fine-tuning the frequency
When connected to a Traditional or Legacy sonar
module or when operating a CHIRP sonar module
in non-CHIRP mode the transmit frequency can be
ne-tuned.
From the Sonar application:
1. Ensure that the channel frequency that you want
to ne-tune is displayed in the active sonar pane.
2. Select Menu.
3. Select Set-up.
4. Select Sounder Set-up.
5. Select Tune Frequency.
The frequency adjust control is displayed.
6. Adjust the frequency until optimum results are
achieved.
Sonar (Fishnder) application
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