Connecting to CRTN
Quick Guide - Important items to remember when connecting to CRTN:
- Must support NTRIP connection
- Username / password ARE case sensitive
- Base station data type is RTCM3
- Make sure you have the latest firmware in your RTK receiver
- Make sure you have an updated NGS antenna calibration file
- Southern California connection: IP:18.104.22.168:2103
- Northern California connection: IP:22.214.171.124:2103
For CRTN Connection assistance and examples:
- Overview (pdf)
- Technical details (pdf)
- RTK surveying (pdf)
- Troubleshooting tips (pdf)
- North American Vertical Datum of 1988 (NAVD 88) versus California Orthometric Height (COH) (pdf)
CRTN NTRIP account details:
Connection to CRTN requires an NTRIP Username and Password and can be requested by registering at: https://www.surveymonkey.com/s/CRTN_Registration. Username and Password ARE case sensitive. The data stream format is RTCM 3.0. Once you’ve made a successful connection, your data controller will display a list of CRTN base stations for you to choose. If possible, choose the closest base station.
More information on NTRIP can be found at: http://www.unavco.org/software/data-processing/teqc/teqc.html http://igs.bkg.bund.de/ntrip/ntriphomepage
It may take at least 7-10 business days to receive a CRTN NTRIP login and password. Once you receive your account information, it may take an additional 3-5 business days to troubleshoot connection issues with your instruments. Test your instruments with your CRTN NTRIP account before going out in the field.
CRTN is divided into two sections being north and south. Each section has a different IP address as follows:
- For Southern California (updated February 6, 2018): IP=126.96.36.199, Port=2103
- For Northern California (updated August 5, 2017): IP=188.8.131.52, Port=2103
CRTN base station broadcast CSRS Epoch 2017.50 (NAD83) positions.
A list of the broadcast positions can be found at http://sopac-old.ucsd.edu/docs/CRTN_Access.xlsx
RTK Rover Equipment Settings:
Your RTK equipment must have and support the following items:
- Dual Frequency GPS or GNSS receiver (L1 & L2)
- Internet access modem (cell phone, MiFi device, etc.)
- Support NTRIP connection
- Support RTCM 3.0 data format
Many of the basic RTK settings may be found on the following presentation at: http://csrc-old.ucsd.edu/presentations/2012/Connecting_to_CRTN.pdf
In order to receive updates about the status of CRTN, you will be automatically subscribed to the CRTN Community Notices email list when you receive your CRTN login. Approximately every one to four months, you may receive an email update. If you wish to unsubscribe, please email Maria Turingan at firstname.lastname@example.org.
We recommend that you subscribe to our forum where you can interact with expert users, troubleshoot issues, and obtain more information about CRTN (note the different login and password from CRTN NTRIP account)
To register as a new user on the forum, please go to http://geoforum.ucsd.edu/sopac/ubbthreads.php?ubb=newuser (Note, this link is under construction as of 5/2018)
CRTN is part of a larger organization, the California Spatial Reference Center (CSRC)
To receive CSRC email updates and meeting information, please subscribe by emailing Maria (email@example.com). During the CSRC semi-annual meetings, generally in May and October and alternating between Southern and Northern California, we give presentations and updates about CRTN.
Give a Gift to CRTN. Please do not include any comments online under special instructions. If you have instructions or comments, please email your gift confirmation with your comments to Maria (firstname.lastname@example.org). If you would prefer to send your donation by mail or if you need an invoice for payment of CRTN data services, please email Maria.
In February 2018, the CSRC published a new geodetic datum for California called “CSRS Epoch 2017.50 (NAD83)” under a Caltrans contract to SIO/SOPAC. The new epoch-date coordinates have been embedded in the RTCM 3.0 data streams since March 1, 2018.