Furuno GP-39 User manual

1
Mod
el: GP-39
Using the GP39 as an SCX-21
(NMEA0183) Display and Setting
Device
1. Navigation Display for SCX-21
2. Setting Menus for SCX-21
3. Interconnection and Settings
3.1. Interconnection
3.2. Setting – Operation Mode
3.3. Update Guidance
INDEX

2
Model:
GP-39 with Model: SCX-21
GP-39 version 03.01 software and
above includes a function, which allows
the GP39 to be used as a data display as
well as an initial setting device of the
SCX-21 SATELLITE COMPASS. This
document describes the displays and
setting options, as well as interconnection
and setup instructions.
1. Navigation Displays for SCX-21
The following display pages are added to the GP-39 with v3.01 software and above to
show data from an SCX-21.
Display Example Remarks
Satellite Monitor
In addition to the conventional page,
GNSS satellite display, 4-antenna
display, and masking area display are
also supported.
Heading
The heading data from SCX-21 is
displayed in the same graphical image
as the RD-33, SC-70/130, etc.
3-Axis Speed
3-axis speed is indicated numerically
with arrows to indicate the transverse
speed at the bow and stern.
ROT
T
he ROT meter as well as heading and
SOG helps to see how own ship is
turning.
Attitude –
Roll/Heave/Pitch
The Altitude page shows how own
ship is rolling, pitching, and heaving
graphically and numerically.

3
2. Setting Menus for SCX-21
In addition to the conventional GP-39 settings, the following items are added.
Prohibited GNSS satellite (QZSS, GPS, GLONASS, Galileo)
Offset (Heading, Pitch, Roll, SOG/3-Axis SPD, Air Pressure, Air Temperature)
Smoothing (SOG/COG, 3-Axis Speed, ROT)
DR time
Ship size, antenna location, 3-axis speed position
I/O Setup (Data2, Data3) (Data 2 is output only)
While the SCX-21 has three (3) output ports, Data 1 is used to connect to the GP-
39 and NMEA0183 data is output from Data 2 and 3.
Sample Screens
Offset Smoothing
Ship Size, ANT/CALC-SPD POSN Antenna Position in Illustration

4
3. Interconnection and Settings
3.1. Interconnection
Notes:
(1) When the SCX-21 is connected to the GP-
39, the original antenna GPA-017 or
GPA-C01 CANNOT be used.
(2) In the configuration of an SCX-21 with a GP-39, the GP-39 NMEA0183 output port is occupied
by the SCX-21. In order to output/input data from/to the SCX-21, utilize Data 2 and
Data 3 ports of SCX-21. (Data 2 is output only)
3.2. Setting – Operation Mode
Change the operation mode of the GP39 to make the GP-39 work as an SCX-21 display.
Option 1 – When turning the power on for the
first time…
When the SCX-21 is turned on for the first time,
the Installation menu will launch: Access
[Operation Mode] and select [SCX-21].
(Default: [GP-39]) After changing the mode,
the GP-39 will restart.
Make sure to connect the GP-39 to the SCX-21 – Data 1 port.

Option 2 – If the GP-39 has been turned on
before…
In [Menu] – [System] – [Operation Mode],
select [SCX-21]. (Default) [GP-39]) After
changing the mode, the GP-39 will restart.
3.3. Update Guidance
For a GP-39 with v02.01 or earlier, update to v03.01 or higher to connect to the SCX-
21.
If the GP-39 is already loaded with v3.01 or higher, change the operation mode to
[SCX-21] to use the GP39 with the SCX-21. Set the mode to [GP-39] as default to use
it as a GP-39 with a GPA-017 or GPA-C01 GPS antenna.

FAQ

SCX20 FAQ
Q How can the SCX21 be mounted?
The SCX21 comes standard with a pole mount kit. This kit supports a 1” NPT.
Optional mast mount kit is also available. Part # 001-556-240-00. This kit is used
in combination with the pole mount kit.
The SCX21 can also be surface mounted. Please see the installation manual for
full details.
Q What are the physical dimensions of the SCX21?
3”H x 8”W x 10”L (without pole mount attachment). 2.2lbs

Q What type of connector does the SCX21 use?
The SCX21 uses a 16pin proprietary connector.
Q What connection cable is the SCX21 supplied with?
The SCX21 is supplied with a 15-meter serial data/power pigtail cable. A 30-meter cable is
optional. Part # 001-555-570.
Q How many I/O ports does the SCX20 have?
The SCX21 has one Three (3) NMEA0183 ports. Two (2) NMEA0183 input ports, and one PPS
port for WASSP.
Q What voltage can the SCX21 operate from?
The operating voltage of the SCX21 is 12vdc to 24vdc.
Q What NMEA0183 sentences does the SCX21 output/Input?
Q Sample connection diagram.

Q When the GP39 is connected to the SCX21, what additional displays are
available on the GP39?
Q Does the SCX21 output Heave information for my Furuno Sounder?
Yes, the SCX21 outputs Heave along with pitch and roll.
Q What is the update rate of the SCX20 position/heading information?
The SCX21 updates position and heading at 10hz.
Q Can the output rate be changed and or individual sentences turned off?
Yes. Sentence output rates can be individually changed or turned off completely using a
connected GP39, or via a PC running Tool software.
Q Is the SCX21 compatible with the TZtouch2/3 sensor management
menu?
No. TZT2/3 Sensor management is done over the NMEA2000 bus. The SCX21 is not a
NMEA2000 device.
Q Is the SCX21 affected by GPS blockage and or multipath?
Any GPS sensor or satellite heading sensor can be affected by blockage and or multipath. The
SCX21 decreases these affects by using 4 internal GNSS antennas creating 6 baselines, the
most currently available on the market, for measurement. While the SCX21 can use all 6
baselines for heading, it does not have to. It can calculate heading using only two baselines.
The chance that all 6 baselines would be affected by multipath is decreased. This makes the
SCX21 much more resistant to these issues.

Q What satellite systems is the SCX21 compatible with?
The SCX20 is compatible with GPS, Galileo (EU), GLONASS (Russia), and QZSS (Japan and
Oceania). The SCX20 will track multiple GNSS Satellite Systems for heading calculation.
Q Is the SCX21 compatible with any SBAS systems?
The SCX21 is compatible with the following Satellite Based Augmentation Systems.
Q How can offsets and changes be made to the SCX21?
Offsets and changes can be made to the SCX21 via a GP39, or by a PC running SCX20 Tool
software. Slight heading corrections can also be made by physically adjusting (port or
starboard) the SCX21 antenna. The PC Tool software can also monitor the status of the
SCX21, such as condition, signal reception and blockage condition of all the antennas.
Q How is the SCX21 connected when used with the PC Tool software?
A PC is connected to either Port 1 or 3 using a USB 422/485 converter.

Q Is the SCX21 compatible with the IF-NMEASC?
No. The SCX21 is not compatible with the IF-NMEASC. However, you could use the SCX21 to replace
an SC30/IF-NMEASC installation.
Q What options are available for the SCX21?
Options include mast mount kit, Bird repellents, Snow cover kit, GP39. For a complete list of
available options, please visit the accessories page of the SCX21 on the Furuno USA website.

12/24VDC 12/24VDC
12/24VDC
SCX21
1815
FA70
SILENT MODE
SWTICH
Note: Grey and Purple wires from FA70
power/data cable allows connection to
physical hardware switch to engage or
disengage Silent Mode. When circuit is
closed Silent Mode is activated and when
circuit is open Silent Mode is deactivated.

WIN PC
SCX21
Furuno Part #
422-USB-CBL
422 TO USB Converter
(1 METER)
OR
*Generic 422 to USB
converter can be used*
422-USB-CBL SCX21
(RD-) YELLOW BLUE/GRAY (TD-)
(RD+) WHITE WHITE/GRAY (TD+)
(TD-) ORANGE LTE GREEN/GRAY (RD-)
(TD+) RED YELLOW/GRAY (RD+)
RED (12-24VDC +)
BLACK (12-24VDC -)
RD=RECEIVE DATA
TD = TRANSMIT DATA
SCX21 TO PC
Learn more about marine electronics and navigation on our website.