AL205R ALERT2 Repeater
ALERT2 Repeater
Robust, reliable, and configured to support repeating ALERT2 messages
wetter  wasser  energie  gas flux and turbulence  bauwerke  boden


The AL205R is an ALERT2 repeater/transceiver that is configured to support repeating ALERT2 messages. With two radio I/O, independent receiving and transmitting radios are supported. Three serial ports allow for input and output to several devices, including an ALERT receiver, data logger, PC, and serial server. Local and remote data collection and administration are possible through the micro USB console and Ethernet ports. The USB host port supports flash drives and peripherals to load settings and firmware, as well as to transfer log files from the SD flash drive. Either the GPS or NTP functionality can be used to provide time synchronization, and the LEDs offer status and activity indicators.

The AL205R is suitable for remote, unattended deployments. A co-located data logger can provide local meteorological measurements such as rain, wind, and barometric pressure; provide status information such as battery voltage and intrusion detection; and serve as a communication medium and/or protocol converter for links such as satellite, cellular, and SCADA.

The AL205R supports configurable forward-error-correction (FEC), allowing for the use of 250 ms TDMA time slotting for faster TDMA cycle times and larger networks. The AL205R is firmware-upgradeable, giving you the ability to take advantage of features such as ALERT2 two-way and encryption. 

Note: ALERT2 is a trademark of the National Hydrologic Warning Council.

Funktionen und Vorteile

  • TCIP/IP streaming of received ALERT2 messages and error messages in binary or ASCII format
  • Storage of received ALERT2 messages and error messages via a microSD card
  • Ability to download logs and data in a secure manner via SFTP over a TCP/IP network
  • ALERT2 network device status reporting (battery voltage, temperature, error flags, GPS clock status, and message statistics)
  • Remote reconfiguration of device via secure TCP/IP connection



Operating Temperature Range -40° to +80°C
Power Connector 2 pin, screw terminal
Power Supply 9 to 17 Vdc (reverse polarity protected)
Current Drain at 12 Vdc
  • 96 mA (normal operation, no external connections)
  • ~1 mA (each serial port)
  • ~25 mA (Ethernet port)
  • ~20 mA (GPS on)
  • 144 mA (all serial ports, USB console, and Ethernet connected, GPS on)
RX Radio - Data Out Level 300 to 1200 mV (peak to peak)
TX Radio - Data In Level 100 to 1200 mV (peak to peak, configurable in 0.5 dB steps)
Clock Synchronization GPS or NTP
Clock Drift
  • 2 ppm (0 to 40°C)
  • 3.5 ppm (-40 to +80°C)
  • 3 ports
  • Custom 3-pin cable
  • 1200 to 115,200 bps
Ethernet 10/100 Mb (fixed or DHCP addresses)
Storage microSD expandable storage to record all ALERT2 traffic in ASCII format (N, P, S, C message)
LEDs 10 status LEDs for Power, Bit Sync, Frame Sync, GPS On, Clock Sync, TX Radio Power, Transmit, Serial 1, Serial 2, Serial 3
Active GPS Antenna SMA, female
RX Radio 4 pin, spring clip (power, gnd, data, channel select)
TX Radio 5 pin, spring clip (power, gnd, ptt, data, channel select)
Certifications FCC Part 15 Class A certified
Dimensions 19.05 x 10.16 x 3.18 cm (7.5 x 4 x 1.25 in.)
Weight 600 g (1.3 lb)

Kompatibel mit

The AL205R is compatible with ALERT2 and ALERT networks. Learn more about the ALERT2 protocol at The AL205R integrates well with ALERT2 Administrator for LoggerNet.

The AL205R is compatible with NHWC ALERT2 AirLink v1.1, MANT v1.1, and API v1.0. It supports ALERT2 API input, as well as ALERT2 API and ASCII output. The AL205R implements proposed protocol extensions for the following:

  • Configurable Forward Error Correction
  • Encryption and Authorization
  • End-to-End Reliable Datagram Service

The AL205R offers complete address list support to maintain pass or reject lists based on the source or destination address.


AL205R Firmware v.1.4.1 (34.6 MB) 21-04-2021

Current firmware for the AL205R.

Liste der Änderungen

A2Control Software v.1.4.0 (39.7 MB) 21-04-2021

A2Control software to control and configure the AL205B and AL205R.