0 operating instructions, 1 initial connection and operation, 1 install the supplied sirfdemo on your pc – Navman LA000507 User Manual

Page 12: 2 set up the hardware

4.0 Operating instructions

This section provides important information for the evaluation of the Jupiter 20 GPS module.

Step-by-step instructions for connecting and operating the GPS development kit are included for

first time setup.

4.1 Initial connection and operation

The following steps describe how to connect and operate the GPS Development Kit.

4.1.1 Install the supplied SiRFdemo on your PC:

1. Insert the supplied CD into the CDROM drive
2. Double click on the SiRFDemo software icon and follow the installation process.

4.1.2 Set up the hardware:

1. Connect the DC power adapter to the power input J1.
2. Connect the antenna cable to the SMA coaxial antenna connector on the rear panel of the

Development unit.

3. Connect the DB9 serial data cable between the PC serial communication port and the

Development Unit’s Serial Port 1.

4. Place the antenna in a site where a good view of the sky can be seen (refer to section 4.2 for

more detail).

5. Run the GPS analyser software on the PC. (Refer to section 4.4 for more details.)
6. Connect the power supply to a suitable AC outlet.
7. Turn the unit on using the power switch on the front panel to provide primary power to the

Jupiter 20 receiver. Once power is applied, the Power LED should be lit.

4.2 Positioning the GPS antenna

The GPS antenna should be located with a clear view of the sky for optimal reception of the

satellite signals. The 1PPS LED should begin flashing at 1 Hz once the receiver is powered

and has started receiving at least one satellite. This provides an indication of whether or not the

receiver is running.
Note: GPS signals may be severely attenuated or totally obscured by roofs, solid walls, dense

foliage, or even coated glass (found in many office structures and car windows). The
Development Unit should be outside, or on the roof of a building to effectively evaluate
receiver performance. With stationary developments, care should be taken to keep the
antenna away from the side of a building as GPS signals can reflect off metal or coated
glass. These reflections have a longer path than direct signals and can cause multi-path
errors.

4.3 Connecting an RTCM differential source

For debugging purposes, it is suggested that users log both the GPS and RTCM data

simultaneously. To allow the provision to do this, Navman can supply a software program called

Labmon.

The Development Unit, PC and the RTCM SC-104 differential correction source are connected

as shown in Figure 4.1. If RTCM SC-104 data needs to be logged at the same time it is sent

to the receiver, the OEM must supply a cable with three connectors to connect the RTCM

correction source to the Development Unit’s auxiliary port and to an unused serial port on the

PC. In this case, data is only logged when Labmon is invoked with file names as command line

arguments (refer to the Labmon application note LA010103). Logging and subsequent review of

the RTCM correction data often resolves performance or compatibility issues.