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New Product

Smart Phone/LAN FAX adapter

PCIe / PCIe (M2) Wi-Fi Module

Embedded Wi-Fi to Serial module
    temperature range -40 to +105C

Embedded Wi-Fi AP/router adapter

USB 3.0 to Gigabit LAN

Wireless Sensor (BLE or Wi-Fi)

AIO Network Hub (USB/Wi-Fi/LAN)


PSTN, Dial-Up Modems

By Interfaces -

- PCIe Wi-Fi

- PCIe (M2) Wi-Fi

- Serial TTL, Internal

- RS232, Internal, 12/24/48V

- RS232, Standalone

- USB, Internal

- USB, Standalone

- PC/104

- ISA Bus


By Applications -

- Medical Modems

- Contact ID Modems

- Leased-Line Modems

- Bell 202 Compatible

- Speakerphone Modems


Wireless Modems

Wi-Fi Modems -




Bluetooth Modems

3G Cellular Modems

2.4GHz Transceiver


LAN Products

Serial to Ethernet Modules

USB to Ethernet Adapters

LAN/Wi-Fi/USB/Serial Converter

LAN to Serial/Modem Adapter


PC/104 Products

PC/104 Modem

PC/104 3G Cellular

PC/104 Wi-Fi

PC/104 LAN


Custom Specifications

Build-to-Suit, Wired or Wireless


WHM900 - RF Modem Modules


900 - 928 MHz (ISM Band)

-40C to +85C Operating Temperature

Range - 500 ft with Antenna

256 User Selectable Channels

AT Command Support

Size: 1.0" x 1.0" x o.3"

The WHM900 is a low-cost wireless modem module that operates in the license-free 900 MHz ISM frequency band range.  The WHM900 transfers data up to 1,000 feet with proper antenna.  Its small size, user friendly AT Command support and other unique features, such as low power consumption and Serial TTL interface, make the WHM900 ideal for OEM and VAR integration for high performance RF data communications.  The WHM900 is a FCC Part 15.247 / 15.249 approved RF module and requires no additional FCC approvals.


  • Industrial -40oC to +85oC operating temperature

  • Long range 300 to 500 feet with standard antenna

  • 256 user selectable channels

  • 32 user selectable frequency setting or full range frequency hopping

  • On board NVRAM for storable configuration

  • Low power consumption 36mA / 28mA (TX/RX), 16mA idle mode

  • Power down mode with only 4 mA power consumption

  • AT command support

  • Standard Serial TTL level compatible interface

  • Small size 1.0 x 1.0 x 0.3 (excluding antenna connector)

  • Addressing for point-to-point and point-to-multi point applications

  • Host interface baud rates from 300 bps to 19.2K, plus 57.6K

  • Up to 76Kbps over-the-air data rate

  • Supports hardware (RTS/CTS) and software (Xon/Xoff) flow control

  • Auto link option for unattended operation

RF Modem Development Kit


Radio Frequency 900 – 928 MHz (License-Free ISM Band)


Typically 300 to 500 ft with standard antenna.  Up to 1000 ft with Yagi type antenna
Channels 256 different user selectable channels
Communication Technique Full RF range Frequency Hopping or 32 user selectable frequency settings
RF Data Rate (bps) 1200, 2400, 4800, 9600, 19.2K, 38.4K, 76.8K over-the-air
Transmit Level AT Command selectable range – Max: +0dBm to Min: -20dBm
Modulation Scheme Frequency shift keying (FSK)
Coding Manchester mode
Frequency Separation Fixed at 64KHz intervals
Receiver Sensitivity Data rate and RF frequency  dependent
Data Interface Serial TTL compatible with RS232 definitions
Data Mode Pseudo fill duplex – share transmit and receive data paths to simulate full duplex data transfers
User Interface AT Commands
I/O Data Rate (DTE) 300, 1200, 2400, 9600, 19.2K, 57.6Kbps
Data Transfer Mode 16 bit CRC error corrected mode
DTE Tolerance Over speed / under speed +/- 1%
Receiving Sensitivity - 106dBm @ 2,400 bps
Antenna Connectors Reverse Polarity SMA
Antenna Impedance 50 ohm unbalanced
Antenna Types wave omni-directional type with Reverse Polarity SMA Plug (Male)
Antenna Gain maximum 2 dBi
Voltage Range 3.0V to 6.0VDC operation
Current Consumption 36mA / 28mA (TX/RX), 16mA (Idle Mode), 4mA (Power down mode)
Networking Capability Point-to-point, Point-to-Multipoint
Size (w/o antenna connector) 1.0” x 1.0” x 0.30”
Weight 0.3oz or 7g
Operating Temperature -40oC to +85oC
Humidity (non-condensing) 10 to 90%
Agency Approvals FCC Part 15.247 and 15.249 certified

Development Kit (MDK-2001) Includes 2 each of WHM900 Wireless Modems, Development Interface Boards, RS232 Serial Cables, DB25 to DB9 Adapters, Power Adapters and wave RP SMA Antennas.

Mechanical Diagram & Pin Assignments - WHM900


  1. Pin spacing is 0.100" from center to center.

  2. Dimension of the modem without enclosure - 1.000" x 1.000" x 0.734"

  3. Pin 18 is not provided

  4. Suggested mating female connector: Molex P/N. 90147-1210 (www.molex.com) or equivalent"

  5. Square pins - 0.025" x 0.025"

  6. Tolerance in mechanical dimension is +/-0.002"


Information furnished by Radicom Research is believed to be accurate and reliable.  However Radicom Research assumes no responsibility for its use, or any infringement of patents or other rights of third parties which may result from its use.  Radicom Research reserves the right to change circuitry at any time without notice.  This document is subject to change without notice.

The information contained herein is subject to change without notice. Logos, trademarks and copyrights are property of their respective owners.

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