Hi The uBlox based parts will provide pretty good timing into a directly connected PC. By that I mean, they are on a dedicated USB controller hooked directly to the CPU.
In this context, the objective is microsecond level timing. We’re not after a TimeNut couple of nanoseconds. Even if it’s 10 us, you still get to 0.1 ppm in 100 seconds….. Bob > On Apr 14, 2018, at 12:59 AM, Hal Murray <hmur...@megapathdsl.net> wrote: > > > kb...@n1k.org said: >> The alternative is to plug a USB GPS into the mac and do a bit of code to >> compare things. If you want to pass the gizmo around to your friends …. that >> can be done. Pretty good ones are “sub $10” delivered. > > USB GPS gizmos generally don't have a PPS and the timing on the NMEA > sentences is generally crappy. (I may be biased by a few bad examples.) > > Does anybody have a list of ones known to work well? > > There is at least one GPS-USB with PPS, the Navisys GR-601W/GR-701W/GR-801W, > They were hard to get retail. Looks like idealez sells them Taiwan for $47 > for the 701W (Ublox 7), $50 for the 801W (Ublox 8) (plus shipping). I > haven't tried ordering through them. Gary and/or Mark may have some for sale. > > ---------- > > Plan B is a GPS breakout and a USB-serial breakout and a few wires. 4x less > USB jitter if your USB-Serial chip is full-speed. > > I got mine from SparkFun: > Venus GPS with SMA Connector > https://www.sparkfun.com/products/11058 > USB to Serial Breakout - FT232RL > https://www.sparkfun.com/products/12731 > > ---------- > > Google found this. I don't know anything more: > https://www.zti-communications.com/z050-gps-dongle/ > > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.