Two Way Radio Buying Guide
A two way radio are one of the most convenient as well as economical means of staying in touch with family and friends within a specified region (which is quite substantial). It can be used on an outing to the beach, or a camping trip in the wild, or even while you are out at an exotic location. It simply adds to the excitement without you having to bear any extra expenses.
Types of radios
There are essentially two categories of two way radios - FRS (Family Radio Service) and GMRS (General Mobile Radio Service). The basic difference between these two is that a GMRS radio can have a maximum power output of 50 watts, although regular usage delivers nothing more than 5 watts at best. An FRS radio is even less powerful, delivering a power output of 0.5 watt. Talking in terms of range, a GMRS radio has a range of up to 5 miles, while the FRS version can go upto around 2 miles.
The basic criteria that governs a radio source's range is its power output. The higher the power output, the more would be its range (as is visible from the aforementioned comparison between the two types of radios). For instance, a radio station usually has a power output of 50,000 watts; a base station or mobile radio has an output of upto 100 watts only, while a two-way radio may have the same in single digit figures. Another point to consider here is that two-way radio manufacturers often give you the peak power output of the instrument, which is basically the wattage that would be delivered in ideal conditions, which are, quite frankly, never possible. Hence, it is extremely important that you emphasize more on constant power output rather than peak power.
An apt example of this rating is that peak power output does not consider obstacles like buildings, trees, etc. between two radio sets, a factor that can severely hamper their utility and quality of voice transmissions. Taking a general consideration, these factors are a significant hindrance in the operation of a two-way radio as compared to a plain surface without any obstructions. Talking in numbers, on an unobstructed surface, a power output of 1 watt is capable of clearly transmitting voice signals 1 mile away. This range can be increased by improving upon the power and adding a stronger antenna, but the other side of the coin in that presence of obstructions is going to hamper the voice clarity and range.
Two way radios operate on a technology similar to that of AM and FM radios, with the only difference being that the former allow you to speak as well as listen, i.e., receive as well as transmit radio signals. The technology of signal transmission is based on alternating current, which oscillates at a rate as high as 1,000,000 times per second, and every radio station has its own distinct frequency. Two way radios also have the same principle, with commercial devices capable of broadcasting 6 to 14 frequencies on the VHF (Very High Frequency) or UHF (Ultra High Frequency) bands. The former, i.e., VHF, frequency has a longer range than UHF, given that other factors like power, antenna size, etc. remain same. However, the advantage UHF frequencies hold is that they have a better reach in enclosed spaces like offices, jungles, etc. The main reason why it is important for a group of people to have a specific frequency is to avoid interference from other people who might be having two-way radios and conversing on a different frequency.
Some radio units have embedded rechargeable batteries (Nickel Cadmium or Nickel Metal Hydride), along with a charging stand that needs to be used to recharge them, while others use alkaline (AA or AAA) batteries, while a select few can use both sources according to your choice. So it's basically up to you regarding what is your purpose. If you want to use them remote locations like on camping trips, rechargeable batteries are obviously not the right option. Then again, if you want to communicate within an office, the alkaline ones might be a bit more expensive.
There are a number of additional features that two way radios may have besides vocal communication within a group. Following is a list of some of the most popular add-on features
Adjustable Gain : Radios that have the adjustable gain feature give the control of the microphone's sensitivity in the hands of the user. This is most useful in canceling out interrupting sounds, as well as identifying even the slightest of sounds, depending on the level of sensitivity that has been set
Audio Accessory Connector : The Audio Accessory Connector is a port in the radio that allows the user to connect devices to the instrument, like microphones, speakers, etc.
Auto Channel Change : This feature changes all the radios in the group to a new frequency, in order to avoid interference. However, it is important that all radios within the group must support this feature.
Battery Saving mode : Many radios have a low-power mode that can be used to save battery power in case of situations where there is no point of recharge or availability of alkaline batteries. This mode activates automatically when the radio is not used for a certain period of time, and consumes lesser battery as compared to normal operations.
Cloning capability : This facility allows two radios to be configurable to each others specs (provided that both sets support this feature), which makes setup a relatively easier process compared to the regular procedures. This is particularly useful if you have many radio sets and need to change all of their configurations simultaneously.
Direct Call : This feature allows you to make direct call to one person from within the entire group, with other radio sets being isolated from the conversation. However, in case this feature too, all radios within the group need to be equipped with the same.