Furuno DS-60 Installation Manual page 46

3. MENU SETTINGS
3.2.4 How to correct the ship's speed
Correct the speed error using the test sheet at the back of this manual.
1. Press  to select [SOG Calibration], and press the ENT key.
2. Enter the offset value for the speed over ground, and press the ENT key (setting
range: -12.5 to +12.5%).
3. Press  to select [STW Calibration], and press the ENT key.
4. Enter the offset value for the speed through water, and press the ENT key (setting
range: -12.5 to +12.5%).
5. Press the MENU/ESC key several times to close the menu.
3.2.5 Interference rejection
Interference rejection (Input)
Interference can be detected during a noise test, and the interference may affect the
speed log measurements and readings. To reject the interference, you can use the in-
terference rejection circuit inside the transceiver unit.
The circuit uses the keying pulse (KP) from the external equipment to reject interfer-
ence. External equipment should be connected to the KP_IN terminal.
KP_IN
Required KP output
The interference rejection circuit requires the following KP output. If the interfering
equipment has KP output outside this range, take the measure shown in "How to buf-
fer the KP" on the following page.
0 V
3-6
PCN (66P3950)
TB-4
100Ω
H
3
C
4
5 V to 15 V
Required KP output
CR10
[KP_IN]
Photo
Coupler
Less than 1 V