Computer Automation Technology

WX-250 Weather Receiver with SAME Technology

The WX-250 monitors the NOAA Weather Radio Network which broadcasts continuous National Weather Service information, warnings, watches, forecasts and other hazard information 24 hours a day. This network operates over 800 stations in the continental United States, adjacent coastal waters, Puerto Rico & the Virgin Islands. Along with the routine weather, hazard, and other information the NOAA Weather Radio Network also includes specialized signals designed to alert residents in specific areas about special warnings. By broadcasting these signals, known as SAME (Specific Area Message Encoding), residents can tune in and learn of problems in their own geographical area.

 

 

 

Specific Area Message Decoder
A Digital Signal Processor (DSP) equipped with SAME decoding algorithms is designed to respond to Weather SAME alerts with an audible tone and voice announcements. The WX-250 can be programmed to respond to specific types of warning and/or those occurring in certain cities, counties, or other geographical areas.

Alert Message Timer
At the conclusion of a SAME alert a digital termination signal is transmitted. The WX-250 is designed to decode and automatically shut down the transmitter or, if desired, an internal message timer can control the transmission time.

Repeater Interface
The WX-250 is engineered to seamlessly interface with your repeater. With as few as 4 simple connections, the WX-250 can be set up to provide automatic weather alerts.
During a weather alert, a relay in the WX-250 will disconnect the transmitter from the controller and connect it to the weather receiver. The relay grounds the transmitter PTT line while providing weather audio to modulate the transmitter.

 

 

Alert Start Logic Output
The SAME broadcast includes a signal that is decoded by the WX-250 DSP to produce an external alarm, trigger the controller to execute a specialized macro or automatically load a pre-recorded message.

Alert Stop Logic Output
The WX-250 is also able to respond to a length-of-message signal embedded in the SAME alert. Responding to this signal, the WX-250 will automatically reload a NORMAL memory save.

Weather Enable/Disable Input
Receiver alert control signals are available through the rear panel 15 pin connector. The enable input (when grounded) will enable the receiver. By connecting this input to a controller's user function output switch, weather reports on demand are available. The disable input (when grounded) will inhibit all WX-250 weather alerts, a feature to prevent repeater transmissions from interruption.

Voice Synthesizer Alert Message
Embedded in the SAME message is the time period the warning is in effect. During this time period the built-in voice synthesizer will periodically broadcast the nature of the alert. The voice synthesizer is programmed with several warnings, including "Tornado Warning", Winter Storm Warning", "Flash Flood Warning among many others

WX-250 Printed Circuit Board Assembly
The PC contains a state of the art Digital Signal Processor (DSP) software radio. The DSP contains special algorithms that has excellent SAME sensitivity, byte-wise data quality metrics and advanced error correction. An on-board dip switch allows the DSP frequency synthesizer to select one of 7 NOAA broadcasting stations. The WX-250 interfaces with the repeater through the DB-15 rear connector while the DB-9 connector allows the RS-232 port connection to interface with a PC serial port. The heart of the WX-250 is the DSP, AT89C51ED2 microcontroller and TI voice synthesizer. Since the weather receiver data base (FIP and Event codes) are stored in NRAM, the WX-250 can always be up-dated.

 

Weather Alert Log
As alerts are received, the WX-250 stores the date, time and type of alert in non-volatile memory. Storage is provided for up to 40 alerts. The RS-232 port and the WX-250 configuration editor can be used to download the history data report.

 

WX-250 Configuration Editor
The WX-250 Configuration Editor (see below) included with the receiver requires Microsoft© Windows 2000, ME®, NT®, XP, Vista, Win7, or Win8 operating system. The configuration editor is used to select the FIP codes, EVENT codes, OPTIONS and timer settings.

 

 

 WX-250 Specifications

Available NOAA Channels Channel #1: 162.40 MHz
Channel #2: 162.425 MHz
Channel #3: 162.450 MHz
Channel #4: 162.475 MHz
Channel #5: 162.500 MHz
Channel #6: 162.525 MHz
Channel #7: 162.550 MHz

 

Sensitivity

 

0.5 microvolts for 20dB quiting

Modulation Narrow Band FM, 5KHz Deviation
Antenna 50 Ohm, Type BNC Connector
Relay Closure 2 Form C (DPDT) by Digital Packet
Rear Connectors Interface: 15 Pin D (Female)
Computer: 9 Pin D (Female)
Poweer +12VDC @ 100ma, DC Power
Size 1.75" H x 19" W x 5" D
Operating Temperature -15 to +55 C
   

 

Ordering Infomation

Digital Weather Receiver with rack mount enclosure and
the WX-250 Configuration Editor, a Windows® based
application.
Price: $499.00