Hi At least at this point things like sawtooth correction outputs are still a “who knows if there is one” kind of thing. Doing a GPSDO and not having sawtooth corrected out is sort of a letdown …. Stuff gets better from L1 / L2, but then gets worse when you put hanging bridges back in …. Keep in mind that hanging bridges do not *always* average out.
Bob > On Jan 21, 2019, at 4:43 PM, J. Grizzard <[email protected]> wrote: > > Per the integration guide > (https://www.u-blox.com/sites/default/files/ZED-F9P_IntegrationManual_%28UBX-18010802%29.pdf), > the recommended antenna should be between 30dB and 40dB of gain. > > Additional note: ublox is releasing an eval board (p/n C099-F9P) which is > similar to the sparkfun board, except a less annoying form factor (can work > as a standalone thing, or fit on an arduino), additional interface options > (wifi and bluetooth, pretty useful if you're doing RTK), less annoying > connectors (SMA), and ships with the ublox multi-band antenna ... all for $50 > more than the sparkfun, according to digi-key. They're not available yet, but > I imagine the will be soon. See > https://www.u-blox.com/en/product/c099-f9p-application-board#tab-documentation-resources > for more details. > > On a vaguely related note, I wonder if it would be possible to retrofit > something like a AE6RV GPSDO with one of these. The footprint is pretty > different (and there's a big pile of ground/thermal connections on the bottom > of the new chip), but it seems like the actual electrical interface is > probably the same in the important ways, so it might be possible to make an > adapter board, maybe... > > -j > > On 1/21/19 8:32 AM, Bob kb8tq wrote: >> Hi >> >> Based on the F9P data sheet, you will need an L1 / L2 antenna that is wide >> enough >> to get the Galileo E5B as well as the Glonass L1OF and L2OF bands. The gotcha >> is that (so far) I have not found a gain number for the target antenna. As >> we have >> found on other modules, you do want to get the right gain. L1/L2 antennas >> range >> from 50+ db down to below 30 db. Simply tacking a pad on a 50 db antenna is >> not >> the best way to do things if you are in an urban area. >> >> There also is the issue of powering the antenna. It is not clear what sort >> of antenna >> bias circuit the SparkFun module has on it. If it simply is using the >> module’s bias setup >> that also could be an issue. Max Vcc on the module is 3.6V. The VCC_RF pin >> can have >> main Vcc - 0.1V max on it. If that *really* means that 3.3V is about it for >> antenna bias, >> that eliminates roughly 100% of all the used antennas out there. It also >> eliminates a >> number of the new ones. >> >> If you put in an external bias setup, there are a lot of antennas to pick >> from on eBay. >> They come and go. The used stuff generally will be 12V powered. It also is >> likely >> to have a pretty good data sheet on it. The new stuff from China seems to be >> sold >> by a variety of people who pop up for a while and then go away for a while. >> Making >> sure of what you are getting is a bit tough as a result. There are extensive >> stories >> in the archives ….. >> >> Bob >> >>> On Jan 21, 2019, at 10:21 AM, Graham / KE9H <[email protected]> wrote: >>> >>> What kind of antenna is needed to simultaneously hear all of the systems at >>> once? >>> My PCTel GPS antenna has a filter that limits it to only the US GPS system. >>> >>> --- Graham >>> >>> == >>> >>> On Mon, Jan 21, 2019 at 4:01 AM Dustin Marquess <[email protected]> wrote: >>> >>>> If DigiKey's pricing is accurate, the ZED-F9T is $13.89 more than a >>>> ZED-F9P. I would have gladly paid $14 more for a version of the >>>> SparkFun board using the T(iming) version instead :(. >>>> >>>> On Mon, Jan 21, 2019 at 12:10 AM Bob kb8tq <[email protected]> wrote: >>>>> Hi >>>>> >>>>> From a *very* quick read of the doc’s: >>>>> >>>>> 1) The device *does* have a position hold capability >>>>> >>>>> 2) There is some level of data on the time pulse. It it only 1 ns >>>> resolution? >>>>> 3) It does appear to support Galileo and Glonas in addition to GPS. >>>>> >>>>> 4) It is clearly multi-band for GPS. It is unclear from a quick read if >>>> it is multi-band for the other systems. >>>>> 5) If you get one, make sure you have the RF cable connector it needs. >>>>> >>>>> 6) I have not (yet) found a recommendation for the antenna gain. >>>>> >>>>> Again, all from a quick read …. >>>>> >>>>> Bob >>>>> >>>>>> On Jan 20, 2019, at 5:42 PM, Mark Sims <[email protected]> wrote: >>>>>> >>>>>> Sparkfun is now selling the Ublox F9P L1/L2 GPS receiver module on a >>>> board ($219). The F9P supports GPS/Galileo/Glonass/Beidou and tracks L1/L2 >>>> data. It outputs carrier phase data and has survey-in and fixed position >>>> support along with RTK support (10 mm accuracy). Looks like the F9P has 1 >>>> time pulse output. >>>>>> _______________________________________________ >>>>>> time-nuts mailing list -- [email protected] >>>>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>>> and follow the instructions there. >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- [email protected] >>>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>>> and follow the instructions there. >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
