The Automated Data Service provides up-to-date timing, GPS, and related data in an interactive environment. Most of the files are mirrored on our Anonymous FTP Server. To access the Automated Data Service, log into the server and give the username ads.


The ADS E-mail Server will send by return mail any of the ADS data files. You can obtain a list of available files by sending e-mail to with SUBJECT: index.

For example, using mailx:

mailx -s index

The body of the e-mail can be empty.

To obtain any pariticular ADS file, just send e-mail using the name of the file as the SUBJECT:

mailx -s gpsxp </dev/null
mailx -s lorxp </dev/null

This service extends ADS access to people who normally cannot telnet to the server directly.


Modem service is provided to agencies and activities requiring ADS data via telephone. Access is password controlled; public access via modem is not supported.

PHONES (Area Code 202): 762-1602, 762-1610, 762-1503 (DSN—same numbers w/o area code)
300-14.4Kb (8 bits - No parity - 1 Stop bit)

Our modems are USRobotics Courier HST modems which are compatible with:

  • CCITT V.32bis 14.4K/12K/9600/7200/4800 bps
  • CCITT V.32 9600/4800 bps
  • USR-HST 16.8K,14.4K/12K/9600/7200/4800 bps
  • CCITT V.22bis 2400 bps
  • Bell 212A 1200 bps (also CCITT V.22)
  • CCITT V.23 1200 bps with 75 bps back channel
  • CCITT V.25
  • Bell 103
  • CCITT V.42 LAPM error control
  • CCITT V.42bis data compression
  • CCITT V.54 analog, digital, and remote digital loopback testing
Our modem server will issue the strings:
	"Trying tycho..." 
	"Modem password:"

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