I'm using the Sokkia GSR2700 ISX base and rover with SurvCE 4.06. Since upgrading to 4.06 I've noticed that when storing the reference (base) station as a point under 'monitor/skyplot' the station height is recorded as about 4 inches higher than the value entered when setting up the base.
I've checked and reinstalled my geoid file, also reinstalled SurvCE 4.06 also checked slant boxes ticked and correct heights entered. With 'NGS' boxes ticked or unticked (relative or absolute antenna calibrations) the result is the same. The correct antenna is selected as well, RTK heights at the rover are ok so it looks as if an antenna offset is being subtracted somehow, but only for the base as point record in the points file.
I'll try a few more tests and if the problem persists I'll contact Carlson. I was curious if anyone else has noticed this problem. I've looked through the rw5 file and there are no clues there.
It's useful to record the base as a point as you can add the slant height to the point description, eg 'S1 sh1.543'
There was a bug in SurvCE that caused this to happen previously. see https://surveyorconnect.com/threads/survce-rtk-base-elevation-error.197440/#post-197535&apos ;">here
Thanks Edward. it appears this possible bug is different, you mentioned previously:
If you are using the data transmission protocol RTCM 3.0 and you save the base position in the Monitor/Skyplot - Reference tab, it appears that the software is applying the ARP to phase center vertical offset twice.
This time it's not applying the offset at all but is subtracting the slant height converted to vertical from the phase center to obtain the station height - too high rather than too low.
Will try the other message formats as suggested.