Hello Al, hello Joseph,

first of all, let me wish you all the Best for the Chinese New Year, and I hope you had nice celebrations as well as a good holiday!

Thank you also for your very quick reply to my former problem concerning BT communication of the WBT-201 with my hx4700 PDA !

I would however place in question some other quite important issues of our WBT-201 users group here in Europe. The following is a summary of literally hundreds of postings and discussions which we had!

We are a group of WBT-201 users within the forum "Pocketnavigation" (http://www.pocketnavigation.de/). With more than 116,000 registered users this forum is probably the largest one in Europe dedicated to GPS.
 Basically we all are very happy with the unit, really many fine features for a moderate price!

In the past, we had found problems with the unit:
Earlier, we reported the wrong conversion of TK1 files to NMEA. You adjusted it, thank you for that! You then provided TimemachineX as a test version 2.1.6beta to a single user. While this is a great support, it did not help the community - nobody else of us could test the new version!


We now found further mistakes in the NMEA code generated by TimemachineX from the TK1 log, and would like to check, discuss and hopefully fix that with you. For easier communication, we will always refer to the NMEA file generated by TimemachineX as "NMEA/TMX".


1. The informations for the sentences GSA und GSV are not included in the TK1 file, thus these sentences should not be "artificially" generated by TimemachineX in the NMEA/TMX!

2. Furtheron, we found errors in the RMC and GGA sentences:

We have compared an NMEA/TMX with a simultaneous log done with the u-center software by u-blox, and with an NMEA file converted from the original TK1 with an application which was programmed by one of our users (="OWN").

2.1. RMC:

In the NMEA/TMX the status is always defaulted to "A" (as we see in many files).

$GPRMC,093230,    A,4802.408795,N,00751.671598,E,27.4, 192.0, 050208,,,D*44________________NMEA/TMX
$GPRMC,093230.000,A,4802.4088,  N,00751.6716,  E,27.02,184.11,050208,,,A*5F________________u-center
$GPRMC,093226.000, ,4802.4389,  N,00751.6782,  E,27.55,189.22,050208,,,*0E_________________OWN
__________________| Status A=Valid, V=Invalid
_________________________________________________| Speed over Ground in knots
_______________________________________________________| Course over Ground

Obviously, only RMC sentences with status "A" are logged in the TK1. When the status is "V" the sentence is not logged into the TK1 file, is that right?

This can be clearly seen in the following logs, done parallely with u-center and with the WBT, respectively.

U-CENTER: all RMC sentences are logged, despite of status:

$GPRMC,100029.000,A,4802.7003,N,00751.3024,E,24.04,163.51,060208,,,A*56
$GPRMC,100030.000,A, ... (data omitted for reason of clarity!)   
$GPRMC,100031.000,A,
$GPRMC,100032.000,A,
$GPRMC,100033.000,A,
$GPRMC,100034.000,A,
$GPRMC,100035.000,A,
$GPRMC,100036.000,A,
$GPRMC,100037.000,A,
$GPRMC,100038.000,A,
$GPRMC,100039.000,A,
$GPRMC,100040.000,V,4802.6301,N,00751.3253,E,21.67,171.74,060208,,,N*47
$GPGGA,100040.000,4802.6301,N,00751.3253,E,0,00,99.9,232.0,M,47.9,M,,0000*66
$GPGSA,A,1,,,,,,,,,,,,,99.9,99.9,99.9*09
$GPGSV,3,1,12,03,70,297,13,18,47,081,,21,31,062,16,06,11,111,*74
$GPGSV,3,2,12,27,11,314,,08,05,339,,16,51,194,14,22,46,145,15*70
$GPGSV,3,3,12,19,38,293,,25,12,294,11,15,08,041,,26,07,030,*73
$GPRMC,100041.000,V,4802.6242,N,00751.3266,E,21.67,171.74,060208,,,N*46
$GPGGA,100041.000,4802.6242,N,00751.3266,E,0,00,99.9,232.0,M,47.9,M,,0000*67
$GPGSA,A,1,,,,,,,,,,,,,99.9,99.9,99.9*09
$GPGSV,3,1,12,03,70,297,15,18,47,081,,21,31,062,14,06,11,111,*70
$GPGSV,3,2,12,19,38,293,,08,05,339,,16,51,194,13,22,46,145,15*7F
$GPGSV,3,3,12,27,11,314,,25,12,294,10,15,08,041,,26,07,030,*7A
$GPRMC,100042.000,V, ... (data omitted for reason of clarity!)
$GPRMC,100043.000,V,
$GPRMC,100044.000,V,
$GPRMC,100045.000,V,
$GPRMC,100046.000,V,
$GPRMC,100047.000,V,
$GPRMC,100048.000,V,
$GPRMC,100049.000,V,
$GPRMC,100050.000,V,
$GPRMC,100051.000,V,
$GPRMC,100052.000,V,
$GPRMC,100053.000,V,4802.5706,N,00751.3382,E,0.00,171.74,060208,,,N*7A
$GPGGA,100053.000,4802.5706,N,00751.3382,E,0,00,99.9,232.0,M,47.9,M,,0000*69
$GPGSA,A,1,,,,,,,,,,,,,99.9,99.9,99.9*09
$GPGSV,3,1,12,03,70,297,44,18,47,081,,21,31,062,38,06,11,111,23*7B
$GPGSV,3,2,12,19,38,293,30,08,05,339,,16,51,194,37,22,46,145,41*7B
$GPGSV,3,3,12,27,11,314,35,25,12,294,24,15,08,041,32,26,07,030,26*7E
$GPRMC,100054.000,V,4802.5919,N,00751.4070,E,19.95,101.97,060208,,,N*4A
$GPGGA,100054.000,4802.5919,N,00751.4070,E,0,04,8.6,232.1,M,47.9,M,,0000*55
$GPGSA,A,1,03,16,22,25,,,,,,,,,8.6,8.6,1.0*32
$GPGSV,3,1,12,03,70,297,43,18,47,081,,21,31,062,41,06,11,111,24*75
$GPGSV,3,2,12,19,38,293,29,08,05,339,33,16,51,194,32,22,46,145,43*74
$GPGSV,3,3,12,27,11,314,36,25,12,294,28,15,08,041,23,26,07,030,20*77
$GPRMC,100055.000,A,4802.5953,N,00751.4213,E,23.97,88.63,060208,,,A*6A
$GPGGA,100055.000,4802.5953,N,00751.4213,E,1,04,8.5,232.2,M,47.9,M,,0000*5C

NMEA/TMX: only RMC sentences with status "A" are logged:

$GPRMC,100029,A,4802.700293,N,00751.302399,E,25.2,152.0,060208,,,D*40
$GPGGA,100029,4802.700293,N,00751.302399,E,2,07,2,232,M,15.2,M,999.9,*65
$GPGSA,A,3,14,30,01,05,07,06,47,,,,,,7.38,6.01,4.27*08
$GPGSV,3,1,12,14,67,092,30,22,25,182,16,30,24,040,30,31,49,336,*74
$GPGSV,3,2,12,01,56,341,14,05,08,043,28,07,39,098,36,06,35,088,34*74
$GPGSV,3,3,12,16,44,228,,42,54,141,,20,10,315,,47,22,106,28*7C
$GPRMC,100033,A,4802.672993,N,00751.314597,E,25.7,155.0,060208,,,D*49
$GPGGA,100033,4802.672993,N,00751.314597,E,2,07,2,232,M,15.2,M,999.9,*6E
$GPGSA,A,3,14,30,01,05,07,06,47,,,,,,7.38,6.01,4.27*08
$GPGSV,3,1,12,14,67,092,30,22,25,182,16,30,24,040,30,31,49,336,*74
$GPGSV,3,2,12,01,56,341,14,05,08,043,28,07,39,098,36,06,35,088,34*74
$GPGSV,3,3,12,16,44,228,,42,54,141,,20,10,315,,47,22,106,28*7C
$GPRMC,100055,A,4802.595294,N,00751.421295,E,17.3,126.0,060208,,,D*4A
$GPGGA,100055,4802.595294,N,00751.421295,E,2,07,2,232,M,15.2,M,999.9,*6C

If we are right with our interpretation, it should definitively be OK that only valid RMC sentences are logged.


2.2. GGA:

In the NMEA/TMX the status is always "2" (=DGPS). This certainly is wrong: As you can see in the example below 1) u-center logged status "1", and more important: 2) the conversion of our user indicates that the GGA status is not included (thus: not logged) in the TK1.
Thus, this field should be left empty in the NMEA/TMX!

The same applies for HDOP (always "2"), Number of SVs used (always "07"), and Geoid Separation (always "15.2"), these 3 fields should be left empty in the NMEA/TXT file, because the values are obviously not contained in the TK1 file!

Here are our data examples: again just one line of a given GPS sentence:


$GPGGA,093230,      4802.408795,N,00751.671598,E,2,07,2,  233,  M,15.2,M, 999.9,*6B________NMEA/TMX
$GPGGA,093230.000,  4802.4088,  N,00751.6716,  E,1,08,1.1,233.5,M,47.9,M,      ,0000*5D____u-center
$GPGGA,093231.000,  4802.4009,  N,00751.6708,  E, ,  ,   ,234.0,M,    , ,      ,0000*16____OWN
_________________________________________________| Status 0=Invalid, 1=2D/3D, 2=DGPS, 6=DeadReckoning
___________________________________________________| Number of SVs used
______________________________________________________| HDOP
__________________________________________________________________| Geoid Separation = Alt(HAE)-Alt(MSL)
___________________________________________________________________________| Age of Differential Corrections


3. OK, in NMEA, the number of decimal places with time, latitude, and longitude probably are not important.


4. We would like to add and negotiate some more issues:

4.1. In the past you repeatedly provided beta-versions of TimeMachineX and TMXTool to selected users = those who asked for (including me myself ;>)!

Could you give us permission to post these, and any future versions, in our forum? It would be very valuable "public beta" software for you, and would be helpful for all of us, because we could then test and immediately give you valuable feedback!!

4.2. Hence, it would be helpful both for you, and for us, as keen users, if we could get these documentations:
WBT201-technical-document_1_Protocol.pdf
WBT201-technical-document_2_LOGDATA.PDF
  and could we post these files in our forum?

4.3. Could you maybe provide details about Header/Data/Footer of your file formats (TK1, TK2, TK3, TK4).
In the last version of TimeMachineX a TK4 subfolder has appeared, what are you planning for this??

5. Some additional wishes:

The ANTARIS-Chip has 4 outputs, Target 0 v... 3. We could not find out from which of the outputs the logger gets the data.

Several of our users would like to ask the following: would it be possible to add a programmable feature (through u-center, would require one free target-output) to select which sentences are logged? Possibly with the option to include GSA and GSV at a selectable time interval?
Generally, many of us users would like to have the option to select sentences for the logger!
Maybe this is not feasible for the WBT-201, but we hope that WINTEC as an innovative company will continue the development of the WBT series and develop a device similar to the 201, but based on the new u-blox 5 chip?

One last suggestion for future development: Would it be possible, when the logger is switched off, to have an option to switch off the GPS receiver instead of the BT unit? One of our user would be happy with such a feature.


We are very confident in that our paper might be valuable for you to learn about your user's wishes. The WBT-201 is an excellent unit, and TimemachineX is improving, too.
We definitively highly appreciate WINTEC's support (thank you Al !) and would be happy to continue this by contributing the present list of issues.

We are keen to hear from you, and to contribute to the further development of the WBT-201 and TimemachineX!

With kind regards,
Chris, on behalf of the WBT users at Pocketnavigation