New 10Hz GPS! QStarz BT-Q818XT

Just read about this on a track day forum! Looks ideal for RaceChrono, and it's not that expensive either. Products/BT-Q818XT-F.htm


  • edited July 2010
    Yep, I have one. I will let you know about the test results soon.
  • Antti, always one step ahead :-)
  • No log fonction on this native (non interpolated) 10hz gps ?
  • edited July 2010
    It has no logging function. It seems to be native 10 Hz, but the high throughput (2x compared to 5 Hz) is probably causing some Bluetooth problems. I'm still investigating and trying to sort it out.
  • keep us posted how this 10hz gps performs :)

    btw, HTC HD2 is not working well in 5hz mode. Tried many times.
  • But haven't you used other 10Hz products like the Blackline Fuel GPS? What's different with the QStarz?
  • edited August 2010
    Blackline Fuel outputs different sentences and uses much less bandwidth. It's so frugal that it uses even less bandwidth than 5 Hz qstarz. The QStarz comes with an application that you can modify which sentences are outputted. So I'll run next tests with reduced bandwidth usage.
  • according to their "specifications" page, it's still based on an MTK II chipset...

    Does it mean we could imagine to "overclock" our actual qstarz/iblue/etc... receivers using the MTK II to 10Hz?
  • I have no idea. This 10hz is probably so cheap that it doesn't matter :)
  • I tested this 10hz GPS receiver yesterday, and what I can tell it works fine. Next week i will take it to the track for some serious laptiming :)
  • it's still twice the price of an iblue 747a+ , but yes it's not that much expensive ;)
  • Does the iblue 747a+ has the same MTK II chipset?
    I've ordered a BT-Q818XT and I will have it by Monday. I'm planning to do some tests and upload the results.
  • Motocrosser85: good to hear!
  • Where can you pick up a Q818XT? I can't seem to find it anywhere on the web.
  • edited August 2010
    aol I am confirming the problems you mentioned in 10Hz mode when using bluetooth.
    The Hz rate jumps between 1.4-2-3.3-5-10 all the time. After some tests I made with my Windows Mobile Phone (LG KS20, I'm using WIDCOMM version of Racechrono), I found that the problems start at rates greater than 2Hz* (3Hz, 4Hz, 5Hz, 10Hz).

    I think that it's my phone's bluetooth problem which is horrid tbh.
    When I connect Q818XT to my pc via usb I get the 10Hz easily. At the moment I don't have a bluetooth dongle for the pc or another more stable Windows Mobile Phone to see if I can achieve 10Hz there... When I do, I will inform you about the result.

    And one question: Can you suggest me a cheap phone with wm and a reliable bluetooth? I don't care about the resolution. 320x240 is fine. Maybe some HTC?? Any feedback would be great!

    *You can easily change the refresh rate of Q818XT with "QstarzGpsView v1.2.20" (win xp/vista/7 32-64)
  • Aspaceman where are you from? I too couldn't find it on the web, so I contacted QSTARZ and they gave me information about my local reseller.
  • I reply to my previous post. Bluetooth in general has some issues over 2 Hz... Waiting for advice from qstarz.
    I'm sticking to usb till a solution comes.
  • akiskev, I'm from the Bay Area, CA
  • akiskev: You could try to disable GSV and GSA sentences with the GpsView program, to see if it helps the refresh rate over Bluetooth.
  • edited August 2010
    aol i figured what the problem was. It is a bug of the widcomm stack when using SPP. I' m saying this because I had the same problem when I was connecting my OBD-ii bluetooth reader (SPP) to my phone.
    After some hours of testing I figured out a workaround for this.. It's annoying but simple.
    Take a look... Might give you some ideas...

    I did the same thing with same sucess in my desktop pc (windows 7 64bit, belkin bluetooth adapter which has widcomm too).

    widcomm stack is just horrible in SPP connections. Stay away from widcomm devices!!!
  • thx akiskev for the workaround. tested and works!

    have tried using serial port and all baud rate but none of them work with my HTC Touch HD2 widcomm Bluetooth.

    luckily the workaround works!
  • aol, have you had a chance to test this unit yet?
  • edited August 2010
    Justin I've just uploaded a short incar clip in my youtube account. Data is taken from q818xt at 10hz. Check it out! .
    rx8dorifto I'm glad the workaround worked for you too :D
  • I've just ordered a q818xt to work with a Nokia 5800. The Nokia is running Symbian S60 rather than Windows Mobile, so it will be interesting to see the results.

    If it doesn't work, I can always drop the frequency back to 5Hz if necessary. The price difference between the q818x (5Hz) and q818xt (10Hz) is negligible now anyway, so I don't think it is a big deal if it doesnt work from a financial point of view. It would be a pity from a technical perspective, however.

    Anyone else tried the q818xt with a Symbian phone yet?
  • edited August 2010
    It seems to work alright with my 5800. Haven't tested it on the track, but looks good on simulated runs. I'm actually working on some settings to bring the bandwidth usage down, less or similar to the 5 Hz, so I don't think there will be big problems. I will post the new GPS settings here when I have perfected and tested them.
  • edited August 2010
    I just tried out my new Q818xt with my 5800. I don't understand something. The pairing went easily but when I tried it out around my block- I created a track called my block; I got no times even though the software said 6-9 satellites and the route showed me driving around the block 3 times. While I was doing this there is a big blue screen saying "Waiting..".
    What does this mean? What is it waiting for?
    I need to get this sorted out by Thursday since I will be racing this weekend. Please reply quickly.
    Thanks, Tim
    BTW: How do I delete sessions that did not operate properly. When I look at the list the delete is dim; and 1 press on a session brings me into it and it seems too late to delete it.
  • Xdnbc, have you added a start/finish trap and is it in the right direction?
  • Thank you Adam- my start/finish line was 180* out. The 5 other traps were facing the correct way. I changed the s/f line and got my 5 laps and times- best lap 1.06.31 and top speed 19.8kph.
    BTW: Re: the BTW I added to the previous question, how do I delete sessions from my 5800?
  • I was just looking at the Q818xt manual, and noticed this:

    "Note3: Under 10Hz fix update rate, DGPS function will be disabled"

    I guess that means DGPS/SBAS is disabled while running @ 10hz. I wonder how much this is going to degrade the positional accuracy.
  • JustinHoMi: Wow good find. I did not know that as I don't own a manual.
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