905U-D Wireless Serial

Key Features:

The ELPRO 905U-D Wireless Serial Modem is a license free serial transceiver capable of long-range communications to Operating at 900 MHz and up to 1W, the ELPRO 905U-D provides high-speed RS-232 and RS-485 connectivity up to 115 kbps, which provides a secure two-way wireless serial communications in challenging environments typical of industrial monitoring and control applications.

• 902–928 MHz frequency up to 1W RF power
• Frequency hopping spread spectrum to 115.2 kbps
• 50 x 250 kHz channel spacing
• High-speed RS-232 and RS-485 data rate to 115 kbps
• Transparent/simultaneous broadcast and addressable device messaging
• LoS distance to 20 miles (32 kms) in a single hop; unlimited repeatability
• Low power consumption mode with DTR control
• Forward error correction communications (CRC error checking with ARQ)
• Simplistic configuration for AT Hayes commands or Windows-based software
• Helpful diagnostics include radio signal strength and BER Indication

Product Details

Transmitter and Receiver

Frequency 902–928 MHz , 915–928 MHz

Transmit power 1W

Transmission Frequency hopping spread spectrum (FHSS)

Modulation Frequency shift keying

Receiver sensitivity –106 dBm @ 19.2 kbps, –103 dBm @ 115.2 kbps (1% FER)

Channel spacing 50 x 250 kHz

Data rate 19.2–115.2 kbps

Range (LoS) 20 miles (32 kms) @ 4W

Antenna connector 1 x female SMA standard polarity

Serial Port

RS‑232 DB‑9 female DCE, RTS/CTS/DTR/DCD (hardware signals  provided)

RS‑485 2‑pin terminal block (maximum distance 4000′ (1.2 km),  non‑isolated)

Data rate (bps) 1.2–115.2 kbps, configurable

Serial settings 7 or 8 data bits, stop/start/parity bits configurable

Protocols and Configuration

System address Configurable 8‑bit value (0–255)

Protocols supported Operating mode, radio and serial settings

User configuration Windows‑based software or AT Hayes commands via serial port

LED Indication and Diagnostics

LED indication Power/OK, radio TX/RX, serial TX/RX, DCD

Reported diagnostics RSSI measurement (dBm), bit error ratio (BER)

Power Supply

Nominal supply 10–30 Vdc, under/over voltage protection

Average current draw 70 mA @ 12V (idle), 50 mA @ 24V (idle)

Transmit current draw 350 mA @ 12V (1W), 250 mA @ 24V (1W)


EMC FCC Part 15 Class A

RF (radio) AS/NZS 4268, FCC 15.247

Hazardous area CSA Class I Division 2

Safety AS/NZS 60950, IEC 60950


Temperature rating –40 to +140°F (–40 to +60°C )

Humidity rating 0–99% RH noncondensing