Not being an expert on corrections, what corrections are transmitted from the base to rover? Base position N, E, Up (or X, Y, Z) or PRN 01 (02, 03, etc) correction ± to range?

Is the correction selectable?

When it comes to already established bases, what correction formats are available? That is if you dial up your County Corrections Center can you choose the format you want and/or do you set your PM3 to accept what you get?

Pal in PA

Paul,
I'm going to through out what I think is being done and what I know. Others will jump on I'm sure to provide info they have dug up or know. BTW, it was nice meeting you in Hershey at PAPLS Conf.

Most permanent base stations I've established are setup to broadcast WGS84 Lat., Long & Ellip Ht. This correction can be typically setup to be broadcast over a UHF radio, at basic, in RTCM 2.3 or 3.0 format or CMR/CMR+, or old Ashtech DBEN. Some base receivers can be set to output one format to Port A, another type to Port B. The Rover will pickup this data packet every 1 sec (typically) with the base coords transmitted 1x per minute and based on localizations used to tie to existing control monuments, you collect or stake out points accordingly. Meaing, you localize to 5000 , 5000 , 100 and your survey is on a local system...

PM3 RTK units will support receiving RTCM 2.3 or 3.0 message formats from RTN's, such as VRS or Spyder. TopNet is still being ironed out, but I've personally tested my PM3RTK Rover in a Spyder & VRS environment.
Modified By Ben Sullivan on 1/22/2008 at 10:39 PM