Wireless WeatherHawk™ Frequencies

 

You may wonder why WeatherHawk™wireless systems are available in three different radio frequencies: 916 MHz, 922 MHz, or 2.4 GHz.

You may also wonder which frequency you should consider and why it is important.

The tutorial below should answer the above questions. However, if you still need assistance please contact your local WeatherHawk Service Center, or Authorized Dealer for assistance.

Radio Frequency Rules Summary

There are many different applications for wireless equipment. This means that literally thousands of products are available to provide wireless voice, video and data transmission using radio frequencies (RF). Some frequencies are better for some types of RF transmission, and this depends on many factors including available power, information content (voice, data, video), transmission technology, range and the ultimate user. In addition, some RF bands have been specifically allocated for use by the government, the military and emergency services.

If there were no regulations for who could use RF, or what was transmitted, there would be chaos because the most powerful transmitters would dominate the airwaves. For this reason, governments of various countries have defined specific frequency bands, and power levels within those frequency bands for use by various users, using various types of equipment.

Regulated and Unregulated RF

The high power level, long range frequency bands are strictly regulated, and use of these RF bands require that a license be obtained by the transmitter operator. This license is obtained from the Government regulatory agency where the transmitter is located, and the license covers the region, or application served by the licensee. The standard WeatherHawk does not use radios that operate in licensed RF bands.

Some low power RF frequency bands have been designated as "unlicensed", and these are used by anyone with equipment designed to operate in that RF band. A range of companies make products that include household wireless telephones, garage door openers, personal walkie-talkies, wireless computer networks, etc. Their output power, RF technology, and frequency specifications generally limit them to very short ranges, most are under 100 feet. Most short range systems available today also use digital encoding that further limits interference between systems operating on the same RF frequency. Digital encoding is why all of the wireless garage door openers on a street can have the same center frequency, yet be only a few feet apart and still only open when the companion controller is used.

There are also higher power unlicensed RF bands for data transmission that use spread spectrum RF technology. These systems are designed to operate at center frequencies in the 900 MHz band or at 2.4 GHz, depending on the country where the transmitter will be located.

The 900 MHz band is further restricted by its center frequency to 916 MHz for the Americas, and 922 MHz for Israel and Australia. Although these frequencies, and the 2.4 GHz frequency are "unlicensed" it does not mean that they are "unregulated" because "all" RF transmitters are subject to regulations in almost every country in the world.

It is important that you purchase the proper system for your country and region because in many countries it is a crime to operate a transmitter that is not in compliance with regulations. Depending on the country involved there may be civil or criminal penalties, or both; and many countries actively search for non-compliant transmitters.

WeatherHawk Spread Spectrum Radios

WeatherHawk radios are manufactured by MaxStream Corporation. MaxStream designs, manufactures and tests their radios to be in compliance with all applicable regulations, if they are used in accordance with local Laws and Regulations. Please use the MaxStream link above if you are interested in learning more about these radios and the company that makes them.

In general, WeatherHawk wireless weather stations can be used in the following countries:

WeatherHawk 916 MHz System (Model #WeatherHawk 916)

The Americas - including the USA, Canada, Mexico; all Central American Countries, all South American Countries.

NOTE: For Central and South American countries there may be local licenses or testing required before a wireless system can be placed into service. Check with your local WeatherHawk Service Center or Dealer for more information.

WeatherHawk 922 MHz System (Model #WeatherHawk 922)

Australia and Israel

WeatherHawk 2.4 GHz System (Model #WeatherHawk 240)

The Americas, Asia, Japan, Africa, the UK and Europe

NOTE: Although 2.4 GHz is the established frequency for the UK and Europe, some countries additionally restrict the use of any RF system. Check with WeatherHawk (UK) for regulations within the European Economic Community.

 

Why not use a 2.4 GHz WeatherHawk in the USA?

It is permissible to use 2.4 GHz wireless WeatherHawk systems in the USA, and they are not subject to special regulations. However, the higher the spread spectrum center frequency (at the same power level), the shorter the transmission range.

A 916 MHz WeatherHawk will achieve reliable line-of-sight (LOS) range up to 1/2 mile, and the long range system can reach 6-7 miles LOS. Compare that to the 2.4 GHz system ranges of 1/4 mile LOS (standard) and 3.5 miles LOS (long range).

Why don't WeatherHawk radios interfere with each other?

All WeatherHawk radios in a given region are operating on the same center frequency. In the USA it is usually 916 MHz, and it is possible for a WeatherHawk to send its data to the wrong base station, and for a base station to receive data from the wrong WeatherHawk. However, this is not possible if the set-up instructions are followed when a WeatherHawk owner receives their system.

Every WeatherHawk has a unique serial number, and every data logger in a WeatherHawk can be programmed with a unique address. In addition, the software delivered with WeatherHawk (Virtual Weather Station) is designed to recognize a specific WeatherHawk by data logger address. So even though all WeatherHawk's are transmitting on the same frequency, they have all been given a unique identification number (data logger address) and their base station software only recognizes that number.

This feature is what allows Virtual Weather Station software to be configured for more than one WeatherHawk. This also enables a single base station/computer set to manage many WeatherHawk's in a given region by simply assigning a unique data logger number to each weather station, then creating a matching configuration file in VWS for every WeatherHawk in the network. A typical application for a multiple WeatherHawk network is a vineyard, where different micro-climates need to be monitored for frost conditions.

We hope this brief tutorial on WeatherHawk radios and RF transmission regulations has been helpful. If you have additional questions please contact WeatherHawk, or a WeatherHawk Dealer directly.