Humminbird 77c manual Finding the Cause of Noise, Matrix Fishing System Accessories, Isolation

M77_Man_Eng_531350-1_B.qxd 1/3/2005 4:30 PM Page 56

Finding the Cause of Noise

Electrical noise usually affects the display with many black dots at high speeds, and high sensitivity readings. One or more of the following sources can cause noise or interference:

Possible Source of Noise	Isolation
Other electronic devices	Turn off any nearby electronic devices to see if the
	problem goes away, then turn them on one at a
	time to see if the noise re-appears.
The boat’s engine	To determine whether the boat’s engine is the
	source of the noise, increase the RPMs while the
	boat is in neutral and stationary to see if the noise
	increases proportionately; if noise appears when
	you rev the engine, the problem could be the spark
	plugs, alternator, or tachometer wiring. Replace the
	spark plugs with resistor plugs, install an alternator
	filter, or route the control head power and
	transducer cables away from the engine wiring.
Cavitation from the boat’s	Turbulence created by the propeller can cause
propeller	noise; make sure the transducer is mounted at least
	15” (38 cm) from the propeller, and that the water
	flows smoothly over the face of the transducer at
	all times.

Matrix™ Fishing System Accessories

Accessories customize the Matrix™ Fishing System to your needs and enable you to stay on the edge of new technology. When an accessory is connected to the Matrix™ Fishing System, additional menus and readouts are added automatically to the Main Menu System. Accessories available today that are supported by your Fishing System include:

Temperature/Speed: purchase and plug in the Temperature/Speed accessory to your Matrix™ control head to get real time speed and temperature readouts, as well as a valuable Triplog function.

NOTE: If an external Temperature/Speed (TS-W) or Temperature (TG-W) accessory is connected AND a transducer with temperature built in is connected at the same time, the TS-W or TG-W accessory will override the temperature which is built in to the transducer.

WeatherSense® Fishing Condition Monitor: purchase and plug in the WeatherSense® accessory to your Matrix™ Fishing System to obtain barometric pressure readouts and trend data in real time.

GR4 GPS Receivers: purchase and connect the GR4 GPS Receiver to your Matrix™ Fishing System to access advanced FishingGPS™, trackplotter and navigation capabilities built-in to your Fishing System.

GPS Connection Cable: purchase the GPS Connection Cable in order to connect a handheld or other NMEA* GPS-compatible device that you may already own to your Matrix™ Fishing System.

Wireless Sonar Link (WSL) purchase the Wireless Sonar Link (WSL) accessory to receive remote sonar signals from a SmartCast® Remote Sonar Sensor (RSS). Radio signals from the RSS are received by the WSL and transmitted over the Accessory Bus to the Matrix™ Fishing System.

PC Connect Cable: Purchase the PC Connect Cable to connect the Matrix™ Fishing System to a PC in order to upload product software updates and new features obtained from www.humminbird.com. This accessory requires the MSWindows-compatible HumminbirdPC™ software downloaded from our website to your PC in order to communicate with the Matrix™ Fishing System.

Be sure to check out our website www.humminbird.com for additional new and exciting accessories to grow your Matrix™ Fishing System!

NOTE: Each accessory requires a separate purchase. You can visit our website at www.humminbird.com or contact our Customer Resource Center at 1-334-687-0503 for additional details.

*NMEA 0183 is a National Marine Electronics Association standard for data communication.

51 52