Re: [time-nuts] eBay GPS antennas

As I was saying, indeed. There is a huge difference between affordable gear and cutting edge gear in price and performance. With GLONASS there are several extra biases to worry about. It would be nice if prices of these things could drop. Already having GPS, GLONASS, GALILEO, BEIDOU on my

[time-nuts] eBay GPS antennas

Javad charges an extra us$1500 for "GLONASS .2mm Dynamic Calibration" of its triple-frequency timing receiver board: http://www.javad.com:80/jgnss/products/options/gclb.html https://www.javad.com/dynamic/Shop/Product/3268 (the TRE-3 appears to be the only triple-frequency part with the "Precise

Re: [time-nuts] eBay GPS antennas

Hi, A complicating factor with GLONASS is the frequency separation of the satellites which causes several aspects of calibration issues. I know they have changed operational aspects which have reduced uncertainty significantly. This is also something that have been worked at with the GPS system

Re: [time-nuts] eBay GPS antennas

On 2/16/18 10:47 AM, Bob kb8tq wrote: Hi Well, the interesting point about Glonass timing is that it is independent of the GPS empire. Galileo is another independent time source. Running a GPSDO linked to each one would let you inter-compare the time from each of them. Indeed I would *guess*

Re: [time-nuts] eBay GPS antennas

Hi Part of the issue with Glonass is the accuracy of the datum. It *can* be used for navigation and timing. It’s best to use it stand alone. Survey a location that is specific to it’s datum and then lock the module into timing mode. Don’t try to run with a GPS survey as your location. All that

Re: [time-nuts] eBay GPS antennas

Yo Bob! On Fri, 16 Feb 2018 13:47:24 -0500 Bob kb8tq wrote: > Reports to date on Glonass have not been encouraging. I have been testing position accuracy lately on a self contained u-blox 8 with built-in antenna supposedly GLONASS capable. I write a Python script to selectively

Re: [time-nuts] eBay GPS antennas

Hi A full blown choke ring antenna is a pretty big heavy gizmo. That said, yes indeed, some shipping charges are insane. Bob > On Feb 16, 2018, at 1:51 PM, Wes wrote: > > On 2/16/2018 11:31 AM, Stewart Cobb wrote: >> ... >> >> For example, any AeroAntenna whose part

Re: [time-nuts] eBay GPS antennas

On 2/16/2018 11:31 AM, Stewart Cobb wrote: ... For example, any AeroAntenna whose part number starts with "AT2775" is a dual-frequency L1/L2 GPS antenna. AT2775-42 is a near-survey-grade antenna, and one of them is available right now (item 263500294711) at a starting bid of $20, after expiring

Re: [time-nuts] eBay GPS antennas

Hi Well, the interesting point about Glonass timing is that it is independent of the GPS empire. Galileo is another independent time source. Running a GPSDO linked to each one would let you inter-compare the time from each of them. Indeed I would *guess* that Galileo would do pretty well.

[time-nuts] eBay GPS antennas

FYI, Antcom and AeroAntenna are two manufacturers of high-quality American-made GPS / GNSS antennas. Antcom's datasheets are confusing to read, and AeroAntenna hides theirs behind a customer-login barrier, so most of eBay doesn't know exactly what they are. This means that good antennas are often