1. Automated Surface Observing System (ASOS)
“Old” FAA Communications Circuitry
CODEX 3600
modem
ASOS
FAA Air Route Traffic Control Center
ASOS
Data
ALDARS
Data
ADAS
CODEX 3600
modem
CODEX 3600
modem
ALDARS
ASOS
receiver
Leased Telco
AWOS
modem
Leased Telco
modem
AWOS
Data
ALDARS
Data
Point-to-Point configurations
Multipoint configurations
Lightning data injected into ADAS is transmitted to each ASOS.
If ADAS is not used, NLDN is not available and single site sensors are required.
FAA Leesburg Center
National Lightning
Detection Network
(NLDN data)
FAA WMSCR
Atlanta, GA or
Salt Lake City, UT
ZDC
NWSTG

2. Automated Surface Observing System (ASOS)
“Current” FAA FTI Communication Circuitry
ASOS
ACU
Cabinet
FAA ARTCC
J29
Jack
ASOS Data Sets 
 ALDARS
ADAS
ALDARS
Intraplex Switches
receiver
ASOS
ACU
Cabinet
J29
Jack
ASOS Data Sets 
 ALDARS
GDC Modems
Point-to-Point configurations
Multipoint configurations
Lightning data injected into ADAS is transmitted to each ASOS.
If ADAS is not used, NLDN is not available and single site sensors are required.
National Lightning
Detection Network
(NLDN data)
ZDC
FAA WMSCR
Atlanta, GA or
Salt Lake City, UT
NWSTG/RTG

3. Automated Surface Observing System (ASOS) FTI “ASOS” Architecture
SDP
SDP
Analog P-P
(V.13)
TT capable D I G T A L B R E
SDP
GDC
GDC
Modem
ASOS
Modem
Analog
Multipoint
ADAS
SDP
X.25
GDC
GDC
Modem
GDC
Modem
ASOS
Modem
GDC
GDC
Modem
Modem
SDP
SDP
SDP
T1 P-P
961DF TT
Intraplex
Intraplex
WARP
WMSCR
ASOS
Intraplex
Intraplex
Digital P-P
SDP
SDP

4. Automated Surface Observing System (ASOS)
ASOS “FTI Circuit” Problem Resolution
Recommendation:
Issue a loopback “female” connector for each FTI site. Tie wrap the loopback connector to the end of the cable on the J29 jack at the back of the ACU.
A connector at each site will be used as a troubleshooting aid and expedite circuit analysis by the FAA Comms Tech at the ARTCC and the FTI (Harris) PNOCC when required.
==================================================
pin 2 (XMIT) to pin 3 (RCV) pin 4 (RTS) to pin 8 (DCD) pin 6 (DSR) to pin 20 (DTR) pin 17 (RCVR timing) to pin 24 (EXT XMIT timing)

5. Automated Surface Observing System (ASOS)
ASOS “FTI Circuit” Problem Resolution
12:13:50 03/08/ Z DENVER INTERNATIONAL AIRPORT
+­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­+
| UTC WX TS PRECIP SUN SNOW ZR PRESS1 PRESS2 PRESS3 TEMP DEWPT|
|1901 NP [0000 ] |
|1902 NP [0000 ] |
|1903 NP [0000 ] |
|1904 NP [0000 ] |
|1905 NP [0000 ] |
|1906 NP [0000 ] |
|1907 NP [0000 ] |
|1908 NP [0000 ] |
|1909 NP [0000 ] |
|1910 NP [0000 ] |
|1911 M [0000 ] |
|1912 NP [0000 ] |
| |
| HR ARCHIVE |
| ­­­­­+­­­­­+­­­­­+
| | |PAGE |PREV |
| | |TIME |TEST |
| |EXIT |BACK |NEXT |
+­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­+­­­­­+­­­­­+­­­­­+
four “0’s” = operational circuit
only available if the data stream is activated by the FAA at the ADAS

6. ASOS METAR Data Flow ASOS ARTCC - ADAS WFO NCF W M S C R N W S T G
Leased line
FAA
NWS
2400bps Dial Interface
ASOS
Dial Backup  
ARTCC - ADAS
WFO
ANBURS
SAUS27
NADIN-II
ZKC
AWC
AWIPS
SAUS4i
NOAAPORT
SBN
NCF
SAUS70 (sourced by SAUS20)
SAUS80 (sourced by SAUS4i) W M S C R N W S T G
AOMC
All NWS & FAA (soon to Air Force) ASOS report METARS and other products through one of two methods: a – FAA ADAS; b – NWS AWIPS. All CONUS NWS ASOS are migrating to the FAA ADAS for consistency in lightning data reporting.
NWS sponsored ASOS connected to AWIPS through a direct dial up line. If primary connection fails 2 backup AWIPS.
FAA & NWS sponsored ASOS connected to ADAS are through a leased line to NADIN-II. Data is flowing in both directions constantly. Lightning data comes into the ASOS once a minute. No backup if link fails (policy; technically achievable). Something is being replaced – Talk with Jerry
ACRONYMS:
NADIN – National Aviation Data ?? Network
ADAS - ???
ARTCC – Air Route Traffic Control Center
WMSCR -
NWSTG – National Weather Service Telecommunication Gateway
AOMC – ASOS Operations Monitoring Center
NCF – Network Control Facility
AWIPS –
WFO – Weather Forecast Office
SBN – Satellite Broadcast Network
NOAA port – National Oceanic and Atmospheric Administration ???
ABACUS – ASOS BACk Up System
SAUS20 KNKA ( FAA-to-NWS )
SAUS90 KWBC ( NWS-to-FAA )
SAUS70
FAA Users
SAUS80
ABACUS
Dial-backup for Pacific Region ASOS sites when
Connection with ZHN (Honolulu) ADAS fails
FNMOC