Furuno CH-250 manual Troubleshooting, Symptom Check, Remedy

6.6Troubleshooting

The table below provides common symptoms of equipment troubles and the means to rectify them.

Symptom		Check, Remedy
Cannot turn on the	•	Check cable between transceiver unit and display unit.
power.	•	Check ship’s mains.
	• Have a suitably qualified technician check the fuse in the transceiver unit.
Bottom echo becomes	•	Rough seas. Distance to the bottom changes due to rolling and pitching.
irregular.	• Long range selected. Transmission period is longer so ship’s pitching and
		rolling are apt to affect detection of echo.
Weak echo	•	Output power set to minimum. Set to maximum, on the COM1 menu.
	• Excessive TVG. Readjust TVG on the appropriate menu (HORZ, VERT,
		ES). Note that readjustment of TVG is necessary when gain is adjusted.
Somewhat strange	•	[BRILL] key setting too low. Increase brightness with [BRILL] key.
color
Picture contains noise.	•	Equipment not grounded properly. Check equipment ground.
	• Power cable is too close to the signal cable. Relocate power cable or
		signal cable.
	• Debris may be on sea surface. Reject unwanted noise with the
		interference rejector on the COM1 menu.
Picture does not	•	Problem in tilt mechanism or control line. Contact a FURUNO agent or
change when tilt angle		dealer for advice.
is changed. (Bottom is
not displayed in vertical
fan picture when
bottom is flat.)

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