Walkie Talkies, Watts Your Range?

By John Ghysels

 When it comes to Walkie Talkies, many folks get confused by claims of manufacturers about range. It probably would help if someone cleared the air on this, to help out those trying to sort out the ridiculously high claims of range on many Walkie Talkies.  The chart below will simplify things for most folks:

Range Claim         Power         Actual Urban Range  Minimum Range

8-12 Miles           1 watt                  1/2 to 1 Mile             200 Yards

18-20 Miles         2 watts                 1 mile                       500 Yards

27-30 Miles         4 Watts                2 miles                     1000 Yards

Keep in mind that very challeging radio environments will quickly cut your range to the absolute minimum ranges seen here, or to something between this and the urban limits. Only lots of height will get you to the maximums claimed by manufacturers.  In any case, I’m told the manufacturers test their radios under decidedly unrealisitic conditions, using facilities in the unobstructed flatlands of Florida equipped with elevated testing platforms.

Discussion on 2 way radio power:

First off, it is important to remember that the maximum legal power for a GMRS walkie talkie is 4 watts. This is a lot of power, considering that most digital cell phones these days operate on about 300 milliwatts or less, most of the time.  However, cell phones use a near invisible network of “cell” sites all around us, on high building corners, hills and mountain tops, so they seldom have to reach up and out farther than a few hundred yards. For a walkie talkie, which has to do things the hard way, without the help of a cell site, you need lots more power. Also, four watts will drain a battery quickly and requires slightly more expensive, larger and heavier internal compentents to handle the extra energy.

Having said this, anyone who has spent time in the field with these things knows that reliable communications is key. Some settings, such as using radios car to car, on urban streets or in heavily forested areas will cut the range of even the most powerful radio from miles to a few hundred yards. ”Line-of-site” is the rule for radios like this, so if you have height, your range will be greatly extended.  With obstructions, signals may be absorbed or reflected away.

The rule of thumb, even for someone just having fun with these radios, is the more power the better.  That’s why I always recommend spending the extra $20 or so and getting something that uses the legal maximum. Those extra watts will help in punching your signal through metal tinted car winows, through wood frame houses and around concrete structures.  In the wilderness, trees and rocks form similar barriers to radio signals, but as a safety device outdoors the radios really need to perform reliably so the max power makes for more peace of mind in tracking kids and hiking partners. You can always dial down the power to conserve battery juice for when you need it.

Thus, unless you really need the 5.5 inch size of the above Cobra LI5600 radio, you may want to go for the increased power of the 7 inch LI7020, below.

Radios are inexpensive fun for the whole family. When in comes to range however, keep your expectations realistic. Read your instruction manual, keep your settings as simple as possible and go for it in the both real and urban jungles!

John Ghysels, December 7, 2008

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