Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for initiating High Frequency radio communications. ALE is a feature in an HF communications transceiver system, that enables the station to make contact, or initiate a circuit, between itself and another HF radio station or network of stations. The purpose is to provide a reliable rapid method of calling and connecting during constantly changing HF ionospheric propagation, with or without skilled operators, through the benefits of processor control. The common basic protocol standards for ALE are MIL-STD 188-141 and FED-1045, known as 2G ALE or 141 ALE. Newer standards of ALE, that use accurate time synchronisation to achieve faster and more dependable linking, are known as 3G ALE. ALE techniques include automatic signaling, selective calling, automatic handshaking, and automatic station identification. Other automatic techniques that are related to ALE are channel scanning and selection, link quality analysis (LQA), polling, sounding, message store-and-forward, address protection, and anti-spoofing. Optional ALE functions include polling and the exchange of orderwire commands and messages.
Automatic Link Establishment in International Amateur Radio
Amateur Radio (Ham Radio) uses the Automatic Link Establishment ALE open network. Ham radio has developed a flavor of ALE that utilizes common denominators of ALE protocols, enabling any manufacturer's radios or software to be utilized for interoperative communication and networking. This is a versatile system for connecting operators for voice, data, text, instant messaging, or image. A radio operator initiating a call, can within minutes have the ALE automatically find and pick a frequency that has a good ionospheric propagation path. It signals the operators on both ends, so they can begin communicating with each other immediately. In this respect, it can eliminate the longstanding need for repetitive calling on pre-determined time schedules and tedious monitoring static on HF. It is a great tool for finding optimum propagation between stations in real-time, while avoiding guesswork, beacon listening, and complicated HF prediction charts altogether. ALE is most commonly used for hooking up operators for voice contacts on SSB (single sideband modulation) and digital texting chat, but there are many other useful features. Each ham radio ALE station uses the operator's callsign as an address in the ALE controller. When not actively in contact with another station, each HF SSB transceiver constantly scans through a list of ALE frequencies, listening for its callsign. To reach a specific station, the caller simply enters the callsign just like dialing a phone number. The ALE controller selects the best available frequency and sends out brief selective calling signals containing the callsigns. When the distant scanning station detects the first few characters of its callsign, it stops scanning and stays on that frequency. The two stations' ALE controllers automatically handshake to confirm that a link is established and they are ready to communicate. The receiving station, which was muted up until now, will typically emit an audible alarm and visual alert for the receiving operator of the incoming call. It also indicates the callsign of the linked station. The operators then can talk in a regular conversation.
International Amateur Radio Automatic Link Establishment Network
The International Amateur Radio ALE High Frequency Network is the world's largest open ALE network. The Channel List for this High Frequency ALE net is frequency coordinated with all IARU Regions (International Amateur Radio Union) for international, regional, and local use in the Amateur Radio Service. All Amateur Radio ALE channels use "USB" Upper Sideband. All channels are subject to the different rules, regulations, and bandplans of the region and local country of operation. Some channels or modes in the frequency list may not be available in every country. This ham radio Automatic Link Establishment network is an open net, and invites all ham radio operators and ham radio nets worldwide to participate in ALE and share the same ALE channels. Ham operators may use it to call each other for voice or data communications. The system provides hot standby nets 24/7/365 for International Emergency and Disaster Relief. High Frequency Internet Protocol or HFIP may be used with ALE for internet access via HF.
CH# Frequency kHz Sideband Common Use Description IARU Region ---- 01- 1806.0 USB VOICE/DATA IARU Pilot R2,3 02- 1840.5 USB VOICE/DATA IARU Pilot R1 03- 1845.0 USB VOICE/DATA =GLOBAL Emergency/Disaster Relief, Interoperation 04- 1996.0 USB VOICE/DATA IARU R1,2,3 05- 3584.5 USB DATA/VOICE IARU R2,3 06- 3596.0 USB DATA/VOICE IARU Pilot R2 07- 3617.0 USB DATA/VOICE IARU R1,3 (Pilot R1) 08- 3626.0 USB DATA/VOICE IARU Pilot R3 09- 3791.0 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation 10- 3845.0 USB VOICE IARU R2 11- 3996.0 USB VOICE IARU R2 12- 5371.5 USB VOICE IARU R1,3 (Emergency R2*) 13- 5403.5 USB VOICE =REGIONAL Emergency/Disaster Relief, Interoperation 14- 7040.5 USB DATA IARU Pilot R1,3 15- 7065.0 USB VOICE =REGIONAL Emergency/Disaster Relief, Interoperation 16- 7099.5 USB DATA IARU R1,2,3 17- 7102.0 USB DATA IARU R1,2,3 (Pilot R2) 18- 7110.5 USB DATA IARU R1,2,3 19- 7185.5 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation (Pilot R3 Aus) 20- 7296.0 USB VOICE IARU R2,3 21- 10136.5 USB DATA/VOICE IARU R1,2,3 22- 10140.5 USB DATA IARU R1,2,3 23- 10145.5 USB DATA =GLOBAL Emergency/Disaster Relief, Interoperation (Pilot All Regions) 24- 14100.5 USB DATA IARU R1,2,3 25- 14109.5 USB DATA IARU Pilot All Regions 26- 14112.0 USB DATA IARU R1,2,3 27- 14342.5 USB VOICE IARU R1,2,3 28- 14346.0 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation 29- 18104.5 USB DATA IARU R1,2,3 30- 18106.0 USB DATA IARU Pilot R2,3 31- 18117.5 USB VOICE/DATA =GLOBAL Emergency/Disaster Relief, Interoperation (Pilot R1) 32- 18157.5 USB VOICE All Regions 33- 21096.0 USB DATA IARU R1,2,3 (Pilot R2) 34- 21116.0 USB DATA IARU R1,2,3 (Pilot R1,3) 35- 21437.5 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation 36- 24926.0 USB DATA IARU Pilot All Regions 37- 24977.5 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation 38- 28146.0 USB DATA IARU R1,2,3 (Pilot R1) 39- 28312.5 USB VOICE/DATA IARU R1,2,3 (Pilot R2,3) 40- 28327.5 USB VOICE =GLOBAL Emergency/Disaster Relief, Interoperation 41- 50162.5 USB VOICE/DATA IARU R1,2,3 42- 144162.5 USB VOICE/DATA IARU R1,2,3
Amateur Radio ALE standards:
1. ALE System = MIL-STD 188-141 ; FED-1045 (8FSK, 2kHzBW) 2. Call or Sounding transmission duration: 30 seconds or less. 3. Scan rate: 1 or 2 channels per second. 4. Sounding Interval = 60 Minutes or more (for same channel) 5. CQ Call = NETCALL to "HFL" net (or "QRZ" on sounding channels) 6. Digi Texting Audio Centre Frequency= 1500HZ to 1800HZ 7. Short text messaging standard = AMD 8. TWS SOUNDING (This Was Sound) 9. "TWS" is always sent to clear link after ALL CALLS or LINKING.
Amateur Radio ALE NETCALLS always use 3 characters:
1. HFL = CQ, ALL AMATEUR RADIO ALE STATIONS (10 member slots) 2. HAM = EMERGENCY LIAISON NET: AMATEUR to NGO/GOV Interoperative (10 member slots) 3. GPR = GEO POSITION REPORTS (3 member slots) 4. RPT = STATION STATUS REPORTS (3 member slots) 5. QRZ = OPEN RESPONSE NET ON SOUNDING CHANNELS (3 member slots) 6. HFN = Ham Radio Global High Frequency Network (10 member slots)
Amateur Radio ALE Timing Standards:
1. Tune Time (TT) max = 1 second (or 1000mSec) 2. Time Wait for Reply (TWR) max = 2 seconds (or 2000mSec) 3. Normal Linked PTT Inactivity (TWA) time out = 6 minutes (or 360 seconds) 4. HFN Pilot Station TWA time out = 2 minutes
Info: This listing is current as of July 2007. For more information about Amateur Radio ALE Automatic Link Establishment and updates of this channel list please see the website: HFLINK.COM
