# Development blog

### 2016-07-20 Time-transfer results from the NVS NV08 GNSS receiver

We have been testing the NVS NV08 GNSS receiver for suitability as a L1 time-transfer receiver.
The CGGTTS data plot below shows a common-clock comparison between a Javad receiver and a NVS receiver, with both receiver antennas having cm-accurate positions. The RMS residual difference between the difference of the two data sets and a linear fit to the same is 3 ns.

### 2016-07-15 First time-transfer results from the ublox LEA8MT GNSS receiver

The ublox 8 series timing receivers can be used for GPSCV time-transfer.
In the CGGTTS data plots below, REF is a Javad receiver, and CAL is the ublox receiver. The receivers
are measured against the same caesium beam standard.
The RMS residual difference between the difference of the two data sets and a linear fit to the same is 4 ns. Some of the noise will be due to imprecise
antenna co-ordinates for the ublox receiver.

Support for the ublox receivers has now been merged into the Develop branch.

### 2016-07-11 CGGTTS v1 versus v2E

Support for CGGTTS v1 output is now fully implemented. CGGTTS v1 specifies use of the full data set whereas

CGGTTS v2E
samples the data set with a 30 s period. In practice, the difference is small. The RMS residual difference between the two solutions in the data set below (Javad receiver) is 0.33 ns.