Communication is a key part of storm chasing and this is especially true if there are a few people in a group chasing together. There are many communication tools in todays world ranging from cell phones to unlicensed FRS walkie-talkies but the best means of communication for storm chasing is ham radio becuase it works when cell phones don’t and the quality and range of communication is far superior to FRS/GMRS and CB.
All amateur radio operators across the globe require a license. In Canada, a basic license will get you privalges above 30 MHz, that means you’ll be able to use all the standard VHF/UHF equipment. I have both my basic+advanced with full privalges except morse code, so I’m able to operate in any of the allocated HAM radio bands.
For storm chasing, all my HAM radio gear is considered mobile equipment. This means, these are radios that are specifically designed to be mounted in a vehicle and operate off the vehicles battery power which is typically in the 11.5 to 14.4 voltage range. These mobile radios typically also have quick keys and features on the microphone and radio face plate which makes operating them easier than a normal base station radio would be.
Most storm chasing communication occurs in the 2-meter VHF spectrum between 144 and 148 MHZ. In North America 146.550 is often the primary FM simplex channel used, with 146.490 and 146.580 being two other alternative channels. Another channel, 146.520 is the FM calling frequency, this is reserved for making contact or calling out for someone to respond. After contact is made it’s standard practice to move to another frequency/channel.
The reason 2-meters is considered the band of choice for mobile communication in rural environments is becuase vehicle mounted antennas don’t have to be overly large to work efficiently, the noise floor is relative low and you don’t need a very good ground plane to ground or anchor the antenna. As you get lower in frequency the noise floor rises, antennas get bigger and the ground plane becomes more and more important. As you get higher in frequency the radio waves become smaller requiring smaller antennas, and the noise floor drops but there is a trade-off. For one, high-frequency radio waves (1.8MHz – 30 MHz) typically have better ground propagation than very high frequency waves meaning that a signal on 50Mhz will in theory travel further through hilly terrain and trees than a signal of the same strength at 145MHz and an ultra high frequency signal at 450MHz will preform even more poorly.
This is all in theory of course. The problem is that a 10m or 6m radio wave requires a big vehicle mounted antenna. A quarter-wave antenna on 10-meters / 29MHz needs to be ~3.5 meters tall, and for 6-meters / 52 MHz you need a ~1.5 meter tall antenna. Yet, for 2-meters / 146MHz a 1.5 meter tall antenna is 5/8th of the radio wave, so your almost at full size which increases you ability to pull in and recieve a signal. When you factor all these real world factors in 2 meters is the ideal band which will get you the most range and signal clarity in a rural mobile environment.
One other aspect of HAM radio which makes it perfect for storm chasing is the use of repeaters. Repeaters are basically half-duplex radio systems mounted high up on towers for maximum range. A repeater recieves a signal on one frequency and immidiately repeats it on another frequency. So if I only had 10 km of range on simplex with a repeater I might be able to get 40 to 100 kilometers of range. This is why Canwarn and Skywarn nets are hosted on repeaters which cover large areas. These nets are activated during severe weather and allow spotters and chasers to relay important information to the net control station who can then directly send it to the proper weather office so a watch or warning can be issued, etc.
In my vehice I have two radios, the first of which is a Yaesu FT-9800R. This radio is a quad-band unit covering 10, 6, 2 and 70 centimeters which basically is giving me access to all the parts of the HAM radio spectrum where FM is used. It also has crossband repeat, dual-recieve and transmit plus 700 memory channels. I’ve put every repeater for the province of Ontario in this radio and have state zones I load in while storm chasing in the U.S and other places. It’s basically my core radio for repeaters and whatever else I might need. However I don’t typically use it for simplex communication.
My second radio is the real workhorse which I use religiously for chaser to chaser communication. It’s the Icom V8000 which boasts a whopping 75 watts of power and is tuned to minimize noise. It’s a mono-band radio meaning it only supports 2-meters but that’s fine, with a good high gain antenna this radio can go the distance. The audio is also super clean. Despite supporting 75 watts it also has low power modes, so I’ll often use it with only 2.5 watts running into a high-gain 5/8th whip antenna.
All my antennas are trunk-lip body mounts. I would use magnetic mount antennas in the past but they would sometimes blow off in high winds, scratch the paint or create other problems. Often they were not sealed well and rain would creep in destroying the coupling system. With trunk-lip mounts the antennas are always firmly in place, well grounded and I’ve not had any corrosion issues. For the FT-9800 I use a quad band antenna called the CR-9800 made by Diamond and for the Icom V8000 I use a Comet 5/8th whip which I’ve cut and tuned. In tornado alley I also sport a CB radio and put on a trunk-lip mounted K40 antenna.