Temp. Offset (Advanced, With Temp/Speed Only); Speed Calibration (Advanced, With Temp/Speed Only); Local Time Zone (Advanced); Daylight Saving Time (Advanced) - Humminbird 700 Series Operating Manual

Temp. Offset will adjust the temperature readout by the amount entered. This
menu option is available if a Temp/Speed Accessory is connected and the
paddlewheel has moved at least once.
Speed Calibration will adjust the speed readout by the amount entered. This
menu option is available if a Temp/Speed Accessory is connected and the
paddlewheel has moved at least once.
Local Time Zone selects your time zone in reference to the time reported by the
GPS receiver when Time+Date is selected as a Digital Readout on the Sonar
View (see Setup Menu Tab: Select Readouts).
Daylight Saving Time adjusts the time display to account for local Daylight
Saving Time when Time+Date is selected as a Digital Readout on the Sonar
View (see Setup Menu Tab: Select Readouts).
Selecting On adds one hour to the time display adjusted for your local time
zone. Selecting Off leaves the time display as adjusted for your local time zone.
Temp. Offset
(Advanced, with Temp/Speed only)
Settings: -10.0 to +10.0 degrees, Default = 0
Speed Calibration
(Advanced, with Temp/Speed only)
Settings: -20% to +20%, Default = 0%
Local Time Zone
(Advanced)
Settings: Various, Default = EST [UTC-5] - Eastern
Standard Time
Daylight Saving Time
(Advanced)
Settings: Off, On; Default = Off
167 Setup Menu Tab