Customs Over The Horizon Enforcement Network
The Customs Over The Horizon Enforcement Network, or COTHEN, provides communications support for more than 235 aircraft, marine interdiction vessels, command offices, and numerous allied agencies including the USCG, DEA, Border Patrol, Army, Navy, and Joint Interagency Task Forces. COTHEN's Technical Service Center (TSC) provides real-time on-the-air support services and guarantees communications between users. COTHEN provides telephone patch (TRICS), a platform tracking and location system (TRACS), and over-the-air-rekeying capabilities (DARK).
COTHEN uses a Rockwell/Collins ALE (Automatic Link Establishment) protocol to connect users to each other over the HF spectrum. If you listen to frequencies in use on the COTHEN network, you will hear the ALE sounding calls which units periodically and automatically initiate to determine the best frequency to use for calls to other units. The Yahoo group dedicated to monitoring this network can be found here
COTHEN Network Frequencies
See this PDF from the UDXF for a much more comprehensive list of frequencies
The COTHEN network now uses the MIL-STD 188-141A protocol. It formerly used the FED-STD-1045A ALE protocol, developed by Rockwell Collins. The FED-STD protocol is Rockwell Collins proprietary and goes by the tradename SELSCAN. SELSCAN is no longer actively used by the COTHEN network.
Note: 8912 kHz is also used by the HFDL (HF Datalink - also referred to as HF ACARS) net
COTHEN Transmitter Locations
Albuquerque, NM 35º 05' 02" N 105º 34' 23" W
Arecibo, PR 18º 17' 26" N 66º 22' 33" W
Atlanta, GA 32º 33' 06" N 84º 23' 35" W
Beaufort, SC 34º 34' 22" N 76º 09' 48" W
Cape Charles, VA 37º 05' 37" N 75º 58' 06" W
Cedar Rapids, IA 42º 00' 09" N 91º 17' 39" W
Denver, CO 39º 15' 45" N 103º 34' 23" W
Fort Myers, FL 81º 31' 20" N 26º 20' 01" W
Kansas City, MO 38º 22' 10" N 93º 21' 48" W
Las Vegas, NV 36º 21' 15" N 114º 17' 33" W
Lovelock, NV 40º 03' 07" N 118º 18' 56" W
Memphis, TN 34º 21' 57" N 90º 02' 43" W
Miami, FL 25º 46' 20" N 80º 28' 48" W
Morehead City, NC 34º 34' 50" N 78º 13' 59" W
Oklahoma City, OK 34º 30' 52" N 97º 30' 52" W
Orlando, FL 28º 31' 30" N 80º 48' 58" W
Reno, NV 38º 31' 12" N 119º 14' 37" W
Sarasota, FL 27º 12' 41" N 81º 31' 20" W
Wilmington, NC 34º 29' 24" N 78º 04' 31" W
ALE Call IDs (Base)
CRB CBP AMOC Caribbean Regional Communications Node
CS1 COTHEN Remote Atlanta, GA used frequently by TSC, voice call "SERVICE ENTER"
CS2 COTHEN Remote Memphis, TN
CS3 COTHEN Remote Oklahoma City, OK
CS4 COTHEN Remote Lovelock, NV
CS5 COTHEN Remote Wilmington, NC
CS6 COTHEN Remote Kansas City, MO
CS7 COTHEN Remote Denver, CO
CS8 COTHEN Remote Albuquerque, NM
CS9 COTHEN Remote Beaufort, SC often used by OPBAT voice call
"PANTHER" and by toms Surveillance Support Center, Jacksonville
voice call "JACKKNIFE"
EST CBP AMOC Eastern Region Communication Node
LNT USCG CAMSLANT Chesapeake, VA
OPB OPBAT Service Center, Nassau, Bahamas, voice call "PANTHER". Also used as
a remote by HAMMER.
PAC USCG CAMSPAC Point Reyes, CA
PNR400 OPBAT base, Georgetown, Bahamas
TSC CBP Orlando, FL Customs National Law Enforcement Communications
Center -- Technical Service Center
WST CBP AMOC Western Region Communication Node
Z01 USCG Sector Northern New England
Z02 USCG Sector Boston
Z03 USCG Southeast New England
Z04 USCG Sector Long Island
Z05 USCG Sector New York
Z06 USCG Sector Delaware
Z07 USCG Sector Baltimore
Z08 USCG Sector Hampton Roads
Z09 USCG Sector North Carolina
Z10 USCG Sector Charleston
Z11 USCG Sector Jacksonville
Z12 USCG Sector Miami
Z13 USCG Sector Key West
Z13PRI USCG Sector Key West
Z13SEC USCG Sector Key West
Z14 USCG Sector St. Petersburg
Z15 USCG Sector San Juan
Z16 USCG Sector Mobile
Z17 USCG Sector New Orleans
Z27 USCG Sector San Francisco
Z28 USCG Sector Los Angeles
Z29 USCG Sector San Diego
Z30 USCG Sector Pudget Sound
Z35 USCG Sector Juneau
Z36 USCG Sector Unknown
Z38 USCG Sector Humboldt Bay
Z58 USCG Sector Unknown
Z81 USCG Sector Unknown
Z99 USCG CAMSLANT Chesapeake, VA
ALE Call IDs (Mobile/Air)
D## CBP P-3/Q200 Detector Units
D01 CBP BOMBARDIER Q400 #N801MR, voice "OMAHA 1MR", Miami AMB, Homestead JARB, FL
D02 CBP BOMBARDIER Q400 #N802MR, voice "OMAHA 2MR"
D2C CBP another address used by D42 9-22-03
D2CS CBP another address used by D42 9-22-03
D03 CBP BOMBARDIER Q400 #N803MR
D05 CBP BOMBARDIER Q400 #N805MR 1-14-09, 3-3-09
D06 CBP BOMBARDIER Q400 #N806MR w/WST 8-29-09
D07 CBP BOMBARDIER Q400 #N807MR w/704, H81, J33 1-21-06, 4-1-06
D14 CBP P-3A "Slick" #N18314/BuNo 150314, Corpus Christi AMB, TX, voice call "OMAHA 314"
D23 CBP P-3B "Slick" #N423SK/BuNo 153423, Corpus Christi AMB, TX, voice call "OMAHA 23SK"
D31 CBP P-3B "Slick" #N431SK/BuNo 153431, Jacksonville AMB, FL, voice "OMAHA 31"
D41 CBP P-3B "Slick" #N741SK/BuNo 152741, Jacksonville AMB, FL, voice call "OMAHA 41SK"
D42 CBP P-3 AEW&C #N142CS/BuNo 153452, Corpus Chrisiti AMB, TX
D43 CBP P-3 AEW&C #N143CS/BuNo 153447, Corpus Christi AMB, TX, voice call "OMAHA 3CS"
D44 CBP P-3 AEW&C #N144CS/BuNo 153446, Corpus Christi AMB, TX, voice "OMAHA 4CS"
D45 CBP P-3 AEW&C #N145CS/BuNo 155299, Jacksonville AMB, FL
D46 CBP P-3 AEW&C #N146CS/BuNo 154605, Jacksonville AMB, FL, voice "OMAHA 6CS"
D47 CBP P-3 AEW&C #N147CS/BuNo 152722, Jacksonville AMB, FL
D48 CBP P-3 AEW&C #N148CS/BuNo 154575, Corpus Christi AMB, TX
D49 CBP P-3 AEW&C #N149CS/BuNo 154581, Corpus Christi AMB, TX, voice call "OMAHA 9CS"
D69 CBP P-3B "Slick" #N769SK/BuNo 152729, Jacksonville AMB, FL, voice call "OMAHA 9SK"
D70 CBP P-3A "Slick" #N16370/BuNo 152170, Corpus Christi AMB, TX
D90 CBP P-3A "Slick" #N15390/Buno 151390, Corpus Christi AMB, TX, voice "OMAHA 390"
D95 CBP P-3A "Slick" #N16295/BuNo 151395, Corpus Christi AMB, TX, voice call "OMAHA 295"
I00 CBP CESSNA 550 #N1200N, Tucson Air Branch
I01 CBP CESSNA 550 #N37201, voice call "OMAHA 201", San Diego AMB
I08 CBP CESSNA 550 #N5408G, "OMAHA 08G", logged on UHF in Seattle
I14 CBP CESSNA 550 #N4614N, Tucson Air Branch, "OMAHA 14N"
I1L CBP CESSNA 550 #N6001L, voice call "OMAHA 01L"
I21 CBP CESSNA 550 #N26621, voice "OMAHA 621", New Orleans AMB
I31 CBP CESSNA 550 #N2531K, San Diego AMB, CA
I34 CBP CESSNA 550 #N2734K, New Orleans AMB
I37 CBP CESSNA 550 #N6637G, Houston Air Unit
I3L CBP CESSNA 550 #N6763L,
I43 CBP BEECH 65-A90 #N43SA, Miami AMB, voice "OMAHA 3SA"
I49 CBP CESSNA 550 #N12549
I4J CBP CESSNA 550 #N5314J, logged on UHF in Arizona,
I52 CBP CESSNA 550 #N752CC, SW US, voice call "OMAHA 2CC"
I53 CBP CESSNA 550 #N753CC
I54 CBP CESSNA 550 #N1254X, Miami AMB
I55 CBP CESSNA 550 #N1255K, Miami AMB
I57 CBP CESSNA 550 #1257B
I62 CBP CESSNA 550 #N3262M
I63 CBP CESSNA 550 #N2663Y
I75 CBP CESSNA 550 #N6775C, logged on UHF in Arizona, "OMAHA 75C", w/OPB
I76 CBP CESSNA 550 #N6776T, voice "OMAHA 76", San Diego AMB, CA
I86 CBP CESSNA 550 #N586RE, logged on UHF in Arizona and Washington
I94 CBP CESSNA 550 #N26494, San Angelo, Houston, or New Orleans based
I96 CBP CESSNA 550 #N26496
I97 CBP CESSNA 550 #N797CW
J01 USCG HH-60J #6001 CGAS Elizabeth City
J02 USCG HH-60J #6002 CGAS San Diego
J03 USCG HH-60J #6003 CGAS Clearwater
J04 USCG HH-60J #6004 CGAS Elizabeth City
J05 USCG HH-60J #6005 CGAS Astoria
J06 USCG HH-60J #6006 CGAS Kodiak
J07 USCG HH-60J #6007 CGAS Sitka
J08 USCG HH-60J #6008 CGAS Astoria
J09 USCG MH-60J #6009 CGAS Elizabeth City
J10 USCG HH-60J #6010 CGAS San Diego
J11 USCG HH-60J #6011 ATC Mobile
J12 USCG HH-60J #6012 CGAS Kodiak
J13 USCG HH-60J #6013 CGAS Clearwater
J14 USCG MH-60J #6014 CGAS Elizabeth City
J15 USCG HH-60J #6015 CGAS Clearwater
J16 USCG HH-60J #6016 CGAS Clearwater
J17 USCG HH-60J #6017 CGAS Clearwater
J18 USCG HH-60J #6018 CGAS Clearwater
J19 USCG HH-60J #6019 CGAS Clearwater
J21 USCG HH-60J #6021 CGAS Kodiak
J22 USCG HH-60J #6022 CGAS Astoria
J23 USCG HH-60J #6023 ATC Mobile
J24 USCG HH-60J #6024 CGAS Kodiak
J25 USCG HH-60J #6025
J26 USCG HH-60J #6026
J28 USCG HH-60J #6028 CGAS Cape Cod
J29 USCG HH-60J #6029 CGAS Kodiak
J30 USCG HH-60J #6030 CGAS Elizabeth City
J31 USCG HH-60J #6031 ATC Mobile
J32 USCG HH-60J #6032 CGAS Cape Cod
J33 USCG HH-60J #6033 CGAS Elizabeth City
J34 USCG HH-60J #6034 CGAS Cape Cod
J35 USCG HH-60J #6035 CGAS San Diego
J36 USCG MH-60J #6036 CGAS Elizabeth City
J37 USCG MH-60J #6037 CGAS Elizabeth City
J38 USCG HH-60J #6038 CGAS Clearwater
J39 USCG HH-60J #6039 ATC Mobile
J40 USCG HH-60J #6040 CGAS Clearwater
J41 USCG MH-60J #6041 CGAS Elizabeth City
J42 USCG MH-60J #6042 CGAS Elizabeth City
Z16 USCG Sector Mobile
The following photos were of a recent Ebay auction of an older COTHEN Marine Mobile Unit. Interesting to note the Parkhill encryption control head and older Adaptive ALE controller (SELSCAN) that the COTHEN network abandoned in favor of the MIL-STD 188-141A ALE Network protocol. Note the COTHEN US Customs Stamp on the equipment.
Note: These photos were reposted with permission of the Ebay seller "Oliver Purddy"
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