BT-359 Bluetooth GPS FAQ
1.) Q: Is this device WAAS enable?
1.) A: Yes, the device is WAAS enabled by default, that are sold by USGlobalSat, Inc and its Authorized Dealers . Note, receivers with firmware 3.1.1 and above are WAAS enable out of the box.
2.) Q: What datum is used?
2.) A: WGS 84
3.) Q: Is this device waterproof?
3.) A: No…
4.) Q: What's the refresh rate?
4.) A: GGA(1sec), GSA(5sec), GSV(5sec), RMC(1sec),VTG(1sec)
5.) Q: How many satellites are needed for 3-D positioning?
5.) A: A minimum of 4 satellites (3 for 2-D no altitude)
6.) Q: Can I reconfigure the receiver? If so, what program?
6.) A: Yes. SirfDemo programming utility. Note, custom settings are temporary until the receiver has exhausted both the Li-ion battery and internal Super-Cap back-up power supply. Then the receiver will revert back to its original default settings.
7.) Q: Can I reconfigure receiver's Baud-Rate? If so, what program?
7.) A: Yes. SirfDemo programming utility. Note, custom settings are temporary until the receiver has exhausted both the Li-ion battery and internal Super-Cap back-up power supply. Then the receiver will revert back to its original default settings.
8.) Q: Can I reconfigure receiver's NMEA data? If so, what program?
8.) A: Yes. SirfDemo programming utility. Note, custom settings are temporary until the receiver has exhausted both the Li-ion battery and internal Super-Cap back-up power supply. Then the receiver will revert back to its original default settings.
9.) Q: What platforms are supported?
9.) A: A better answer. Most devices with Bluetooth communication capabilities. (Check Manufacturer Specs)
10.) Q: Once set, is SiRF Binary Protocol a permanent configuration?
10.) A: These settings are temporary until the receiver has exhausted both the Li-ion battery and internal Super-Cap back-up power supply. Then the receiver will revert back to its original default settings.
11.) Q: What does the Blue LED indicator represent?
11.) A: Bluetooth communication status. Blinking (Slowly)=No Bluetooth connection. Blinking (Quickly)=Bluetooth connection established.
12.) Q: What does the Yellow LED indicator represent?
12.) A: Unit is charging with external power plugged in. Red= Needs charging immediately. Yellow= Battery charging. LED off=Battery fully charge.
13.) Q: What does the Green LED indicator represent?
13.) A: Satellite status. Green LED Flashing=GPS position is fixed. Green LED Steady= No GPS position is fixed and searching.
14.) Q: My GPS shuts down after a period of time. Why?
14.) A: This unit is programmed to shut off automatically after 10 minutes if not communicating with another Bluetooth device.
15.) Q: What's the unit's Bluetooth transmission radius?
15.) A: Ten meters (10m) is unit's maximum Bluetooth transmission radius.
16.) Q: What's the unit's Baud Rate settings?
16.) A: 38400 bps
17.) Q: How does the "20 channel" affect performance? Both: MR350 and BT-359 have "20 channel" in the specs?
17.) A: The sensitivity numbers like the TTFF numbers don't really mean much, as they're hard to tie into real life observations.
18.) Q: How much more power is consumed by the SiRF Star III chipset compared to the SiRF Star IIe/LP chipset?
18.) A: The SiRF Star III chipset is about 15% more power hungry than the previous SiRF Star IIe/LP.
19.) Q: Is the SiRF Star III chipset quicker in signal acquisition?
19.) A: Yes, the SiRF Star III chipset can acquire a signal much faster than IIe/XT2 in difficult environments thanks to the added correlating power, and that is not reflected in the dB number.
20.) Q: What is the charger's electrical specifications (voltage, amps) for this unit?
20.) A: The BT359’s electrical characteristics are 4.5V~5.5V / 0.5A.
21.) Q: How much accuracy is comprised without utilizing WAAS?
21.) A: Since Selective Availability (SA) was removed in May 2000, the residual GPS error of approximately 10 meters is mostly due to GPS signal deflection that the SBAS system can only marginally correct (I have never been able to measure any improvement from EGNOS but others have seen 1/2 meters with WAAS). On the other hand SBAS is crucial for critical use such as flying a plane as it allows for near real time GPS signal integrity checking.
22.) Q: What is the biggest benefit of the SiRF Star III chipset?
22.) A: Correlation power, the action of analyzing the signal received from the satellites and making sense out of it to compute a position. Sounds simple enough, but the signals are very weak (sent from 20,000 kms above our heads) and generally very degraded by our immediate environment, so the more correlation power you have the better your chances are of getting a "fix". In addition, TTFF is less dependent on the environment and once you get a lock you rarely lose it, even indoors. With SiRFIII, GPS requires less "work", for instance, you no longer need to choose between waiting 2 minutes when you leave a parking garage in the morning to get a fix or risk driving around for 10 minutes without one, now you'll generally get a fix in 45 seconds in both situations .
23.) Q: Does the BT-359 support multiple bonding/pairing so it can be used with more than one Bluetooth partner at the same time?
23.) A: Unfortunately, it does not support this feature.
24.) Q: What is the output format for this receiver?
24.) A: Output format: GGA(1sec), GSA(5sec), GSV(5sec), RMC(1sec),VTG(1sec)
25.) Q: What is the current BT-359 firmware version?
25.) A: Firmware version 3.1.1 is the current BT-359 firmware version.
26.) Q: Will my receiver support older NMEA standards?
26.) A: Yes, NMEA 2.0 is backwards compatible with older versions of the protocol. NOTE: If your map software (such as Street Atlas 5) requires data
sentence GGA, and your GPS (such as the Magellan 3000) does not
output GGA, then they will NOT work together.
27.) Q: What is the meaning of "baud rate"?
27.) A: Baud rate is really the rate of bit transitions on the serial data link. Since each byte of data adds a start and stop bit, it is 10 bits long, and 38400 baud is 3840 bytes per second. Faster bit rates transfer more bytes per second, i.e., greater bandwidth.
28.) Q: Can we upgrade our SiRF firmware? What' s needed for the process?
28.) A: SiRF provides the new versions to our direct customers, but it is up to them to determine if they want to provide an update mechanism to their end-user customers. While the process is relatively simple, unless there is a hardware way to put the receiver into flash upgrade mode (internal boot mode is our term) there is a chance to get things stuck so you have to send it back to the manufacturer or a repair depot to recover. Further, you must be supplied with a flash programming utility to do the job since you cannot access the flash directly -- you have to go through the ARM processor on the SiRF chipset."
29.) Q: What is static navigation?
29.) A: Static navigation when enable, velocities lower than 1.2 m/s for 3 seconds we will freeze the position, and leave them frozen until velocity exceeds 1.4 m/s. Static navigation is a mode designed for motor vehicles, which causes the position to become pinned at one location when velocity is determined to be low enough. This is designed to make navigation systems operate more reasonably when the GPS Selective Availability (SA) signal degradation is turned on.
30.) Q: Why is my GPS receiver detected by Bluetooth but no communication is being established to GPSInfo or my third party mapping application?
30.) A: Some BT-359 receivers have been found with the NMEA protocol disable. You may consider using a Bluetooth enabled notebook or desktop and SirfDemo program to switch the receiver back into NMEA mode. If problems persists, continue by removing rechargeable battery for a period of 1-3 hours. This action allows the device to reset.
31.) Q: Why is my date stamp data showing "1985 or 2085"?
31.) A: If your receiver date stamp data shows 2085/09/12 or just 85/09/12. The difference is that 1985 is what the date would be if the receiver thought it was first cycle of GPS weeks rather than the current second cycle (1985/09/12 + 1024 weeks = 2005/04/28). To reset, simply remove rechargeable battery for a period of 20 minutes.
32.) Q: What can I do to prevent my device from having GRMC NMEA time stamp data problem?
32.) A: There is backed battery for SRAM and RTC (Real-Time Clock) to keep last stored position , date ,time , satellite data. When you power down GPS , backed battery will keep the last data. It can help us to achieve maximum acquisition performance. After a long period of time (about 4 hours, depend on different products) GPS is power off, backed battery will run out and last stored data will lose. When you re-start GPS, last stored data display at first if backed battery is still active. If backed battery is inactive , default parameters will display. Only after new GPS signals are received , correct data will display. It can explain why incorrect date display at first. In short , the receiver requires GPS data to update these parameters.
33.) Q: After performing the above. Why is the device's GRMC NMEA time stamp data still incorrect?
33.) A: To correct this problem, remove battery for a period of 10-30 minutes…
34.) Q: Why does my receiver fail to acquire satellite information after in use from a flight?
34.) A: Under GPSInfo, perform a cold start. In result, the BT-338 will reset its registers for terrestrial coordinate calculation.
35.) Q: What the official time is required to fully charge the unit from having the red led flashing?
35.) A: Three to four hours
36.) Q: How important is having WAAS enabled on your GPS receiver?
36.) A: SiRFstartIII currently does not have WAAS enabled, not that this matters unless you intend on relying on it to operate a plane.
37.) Q: What satellite identification number is used for WAAS and EGNOS?
37.) A: Satellite #33 (AoRE) is for EGNOS, Satellite #35 (AoRW) is for WAAS, and it has been suggested that Satellite #41 (PoR) will be used to indicate that data is being received from the Japanese MSAS system.
38.) Q: What is trickle mode?
38.) A: The Trickle mode allows for an increase in battery life by putting the GPS module in sleep mode for very short periods of time, such as 300ms per 1s cycle, which will result in a battery life increase of about 40% according to my testing. It can be useful for certain types of applications but there is a hit on performance as the receiver will have to get "back on its feet" when it wakes up. It is especially problematic in difficult reception conditions. Starting with FW 2.3, SiRF has added the "Adaptive Trickle" mode, which as its name implies will adapt the power savings to the conditions of reception. In optimal conditions, I found that the battery life increase amounts to about 30%.
39.) Q: Why am I not getting any or very weak GPS signals even though my GPS receiver is directly under the windshield glass?
39.) A: Certain vehicles may be equipped with special windshields that contain metal in the glass that prevents GPS and RF signals from being received properly. Customers with these types of windshields must use an exterior GPS antenna for improved results for GPS applications. If you are unsure about whether your vehicle has one of these types of windshields, contact your dealer and request more information. This vehicle list may not be complete and may updated from time-to-time.
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