This configuration covers all Topcon GPS receiver types. Some of these receivers utilize Glonass satellites as well as the standard U.S. satellites. In the Configure Base routine for Topcon GPS, the firmware version of the receiver will be checked and the correct message for setting the base position will be sent according to the firmware version in use.
Note: Glonass refers to the Russian satellite constellation (Global Navigation Satellite System). There are approximately 24 U.S. satellites active (more will launch over time) and there are approximately 10 Glonass satellites currently active. A full “24 satellite constellation” is anticipated by 2006 for the Glonass satellites. With a minimum of 2 Glonass satellites available or “seen” by the base and rover receivers, satellite coverage is improved, and work is sometimes possible in canopy, urban or deep pit environments where non-Glonass receivers do not have coverage. All Topcon GPS receivers have a "stat" light on the front panel that flashes green indicating number of U.S. satellites and orange indicating the number of Russian satellites.
Comm Setup
- Port Number: This drop list allows the user to select the communications port of the data collector.
- This is a Bluetooth Port: This toggle allows the user to specify that the selected port number is in fact the communications port that the Bluetooth device in the data collector is assigned to.
- Find Bluetooth Port: This button will auto-detect the Bluetooth port number in most devices.
- Bluetooth Type: Select the manufacturer of the Bluetooth device if known. Typically, Socket will be the preferred brand and often the installed brand, but if the brand is not known, select Other.
- Baud Rate: Set this value to match the data baud rate of the GPS serial port. Typically this will be 115200 but may also be 9600 or 38400.
- Character Length: Set this value to match the data Character Length of the GPS serial port. Typically this will be 8.
- Parity: Set this value to match the data Parity of the GPS serial port. Typically this will be None.
- Stop Bits: Set this value to match the data Stop Bits of the GPS serial port. Typically this will be 1.
Bluetooth
In addition to the discussion of Bluetooth (wireless) connection found under the help subject Equip - Comm Setup, there are additional trouble-shooting considerations with Topcon Bluetooth.
- Note that the PIN for all Topcon devices is 11111.
- If the OAF file is not current the Bluetooth will not work. An OAF file is used by Topcon for the firmware of their receivers. With an expired OAF file, many features (including Bluetooth) will not work.
- Normally the Bluetooth port (usually B) must be enabled in the OAF file for the Bluetooth to work.
- It is possible to set the Bluetooth port baud rate. Normally it is 9600, 38400 or 115200. This can be checked from the “A” com port using GRIL (command manual for Topcon receivers) commands. The baud rate in the Com Setup should be the same.
Configure Base Station
- Receiver Type: You must select the receiver type (e.g. Hiper Lite).
- Antenna Type: You must select the Antenna Type (e.g. Hiper Lite). See the figure below.


- Antenna Height: This is entered as a vertical or “slant” height in the job units. The Vertical option is measured from the tip of the pole to the unit's ARP (For the Hiper series GPS units, this is the bottom of the unit where the pole screws in). Vertical is typically used for fixed height poles and tripods. For the Hiper series, the Slant option is measured from the point on the ground to the bottom edge of the square housing. This point is approximately 30.50mm higher than the ARP and is located at the bottom edge of the receiver's metal housing and is marked by a small arrow. For detailed information on antenna heights, please see http://www.ngs.noaa.gov/ANTCAL/.
- Elevation Mask: This value establishes the cutoff value above the horizon in degrees where satellites will not be considered.
Configure Base Radio
- Radio Type: There are two options available, PDL or Spread Spectrum. When using PDL, you must define the radio port, baud and RTK message type. When using Spread Spectrum, you only have to define the RTK message type. Most of the modern Hiper series units come with Spread Spectrum radios. When using PacCrest radios, a “TX” light blinks about every second indicating the radio is transmitting. The “RX” light would blink if you were getting interference.
- Radio Port: You must select the radio port. This setting on the TOPCON base and rover receiver is usually C. Data Port is always A when using a cable and B when using Bluetooth. When using Pacific Crest radios, TOPCON recommends the new PDL Pacific Crest radios. These must be set to 38,400 baud rate. TOPCON can also use Spread Spectrum radios, which work at 115,200 baud rate. The HiperLite GPS uses Spread Spectrum radios running at 57,600 baud. The standard Hiper uses Pacific Crest PDL.
- Radio Baud: This defines the over-the-air baud rate that the radio will use. In many cases, the user must know what the radio expects this setting to be based on the radio's firmware or pre-programming.
- RTK Message Type: You must select the RTK message type that you wish to broadcast.
Configure Rover Station
- Receiver Type: You must select the receiver type (e.g. Hiper Lite).
- Antenna Type: You must select the Antenna Type (e.g. Hiper Lite).
- Antenna Height: This is entered as a vertical or “slant” height in the job units. The Vertical option is measured from the tip of the pole to the unit's ARP (For the Hiper series GPS units, this is the bottom of the unit where the pole screws in). Vertical is typically used for fixed height poles and tripods. For the Hiper series, the Slant option is measured from the point on the ground to the bottom edge of the square housing. This point is approximately 30.50mm higher than the ARP and is located at the bottom edge of the receiver's metal housing and is marked by a small arrow. For detailed information on antenna heights, please see http://www.ngs.noaa.gov/ANTCAL/.
- Elevation Mask: This value establishes the cutoff value above the horizon in degrees where satellites will not be considered.
Configure Rover Radio
- Radio Type: There are two options available, PDL or Spread Spectrum. When using PDL, you must define the radio port, baud and RTK message type. When using Spread Spectrum, you only have to define the RTK message type. Most of the modern Hiper series units come with Spread Spectrum radios. When using PacCrest radios, a “TX” light blinks about every second indicating the radio is transmitting. The “RX” light would blink if you were getting interference.
- Radio Port: You must select the radio port. This setting on the TOPCON base and rover receiver is usually C. Data Port is always A when using a cable and B when using Bluetooth. When using Pacific Crest radios, TOPCON recommends the new PDL Pacific Crest radios. These must be set to 38,400 baud rate. TOPCON can also use Spread Spectrum radios, which work at 115,200 baud rate. The HiperLite GPS uses Spread Spectrum radios running at 57,600 baud. The standard Hiper uses Pacific Crest PDL.
- Radio Baud: This defines the over-the-air baud rate that the radio will receive. In many cases, the user must know what the radio expects this setting to be based on the radio's firmware or pre-programming.
- RTK Message Type: You must select the RTK message type that you wish to receive.
Configure Rover Parameters
- Position Update Rate: In Configure Rover, the RTK Calculation Mode should be set to Delay, which forces a fresh reading, as opposed to Extrapolate, which will project the next reading by your direction of movement, and may apply to difficult shots in tree lines.
- Ambiguity Fixing Parameter: This determines how tight the ambiguities of the RTK solution must be before a fixed position is achieved. It is recommended that High be used for greater accuracy.
- RTK Calculation Mode: In Configure Rover, the RTK Calculation Mode should be set to Delay, which forces a fresh reading, as opposed to Extrapolate which will project the next reading by your direction of movement. Extrapolate may apply to difficult shots near obstructions such as trees or buildings.
Receiver Utilities
- Power Cycle Receiver: Use this button to power cycle the receiver. At times this may help if communications fail and cannot be restarted by Configure Base or Rover.
- Restore Factory Defaults: Use this button to re-boot the receiver back to factory default settings.
- Clear Non-Volatile Memory: Use this option to clear the unit's non-volatile memory.
- Send Command to Receiver: This button allow the user to send command directly to the receiver if necessary.
- Set Base/Rover Radio: Use Set Base Radio and Set Rover Radio to be sure that both radios are on the same channel. Recommended settings are base on low “digisquelch” (low sensitivity) and rover on medium or high digisquelch.
- Set Satellite Status: This command enables you to “turn off” particular satellites, both U.S. and Russian. In SurvCE's Monitor/SkyPlot command, located on the Equip tab, the Sat Info screen displays the Russian satellites numbered 45 and up and the U.S. satellites numbered from 1 to 24.
- Initialize to Known Point: Use this option to speed up the initialization process.
Post-Processing
All Topcon GPS receivers can be used for post processing and will store raw GPS data on the on-board RAM in the receiver. The post-processing can be activated by the Log Static Data command found in the Survey menu of SurvCE. On every receiver, you can also activate logging purely through hardware by holding down the FN key, watch the light turn orange to green, then release. To turn off by hardware, press FN until the light turns off. Since SurvCE will prompt for antenna height, type and other parameters, it is recommended that software be used to initiate logging. Topcon logging files typically start off with the word “Log” followed by the date, and are post-processed using Topcon Tools. Topcon Tools will output a Rinex ASCII file of the logging data for use with programs such as NGS’s OPUS.