2-way Radios

Radio model considerations

•  0.5 to 1-Watt power.  Usually claimed to have 5km transmission range.
•  1 to 2-Watt power.  Usually claimed to have 8km transmission range.
•  2 to 3-Watt power.  Usually claimed to have 12km transmission range.
•  Over 3-Watt power.  Usually claimed to have very long range.
Yeah, right... in the middle of the Gibson Desert at midnight, perhaps.
In the real world hills, trees, buildings, vehicles... even your own body reduce transmission range.  The 0.5W ‘toy’ radios are cheap but limited to much less than 1km REAL transmission range – usually only a few hundred meters.  The 1-2W units are good for road use with about 2km actual range, 3W units range out to about 4km on average, and 5W units reach out to more than 5 or 6 klicks.  Y’ gets what y’ pays for, though.  Up until recently, 2W radios were about twice the price of 0.5W units, 3W units about 3 times, and 5W units about 4 times.  That’s all changing now.  5-Watt radios from China are available online, and cost less than AU$100... about the same as the ‘toy’ radios!  So the price difference between short- and long-range models is becoming less important.
The main problem is the small aerial on hand-held radios – they aren’t very efficient, and the antenna is a bigger influence on transmission range than the power of the radio.  Radios of lower power... 0.5-Watt up to about 2-Watt, all have fixed antennas, usually stubby little eighth- or quarter-wave ones.  Taller half-wave antennas ( about 20cm high ) increase range, but you can’t use one if the radio has a fixed antenna.  Detachable antennas, which are commonly fitted to radios of 3-Watt power or more, are much better.  You can either attach a larger one for better range or use an external full-wave antenna for maximum range, and quite cheaply, too ( less than $50 ).