FRS - Family Radio Service - Channels designed for family recreational use only. You DO NOT need a license to operate on these channels.
GMRS - General Mobile Radio Service - Channels also designed for family and recreational use but allow for a bit more communication distance than the FRS channels. These channels allow for the ability to use detachable antennas and repeater stations to lengthen the distance of communication. You WILL need a license to operate on these channels though it is not regularly policed.
VOX (Voice Activated Transmit)
Feature on two-way radios that allow for you to use the radios handsfree. This feature is sound activated so all you do is speak and the radio will transmit for you.
A feature that helps filter out the chatter from other users who might be using the same frequency. Common misperception is that the conversation is private when using this feature. IT IS NOT. Your conversations can still be heard by users who set their radio to not filter for a privacy code.
Button on the radio (and some headsets) that you press to transmit.
Tone that let's the other two-way radio users know when you are done with your transmission.
Locks your keypad to prevent unintended changes to your settings while being bumped around.
Ni-Cad, NiMH, or Li-Ion - Different Types of Batteries
Ni-Cad - (Nickel Cadmium) - Long life expectancy and rarely have issues in regards to over charging. Usually will last up to 3 years.
NiMH - (Nickel Metal Hydride) - Usually lasts up to 2 years and have overcharging issues if proper charging practices are not used.
Li-Ion - (Lithium Ion) - Life expectancy is based off of number of charging cycles (500, 1000, etc) once reached the battery will no longer work. Usually charges extremely fast and do not have issues with overcharging.
***Proper technique when using your radios is to allow the battery to completely deplete before recharging. If you do not, the battery will recall the partial charge and only charge up to that point the next time around.
Noise Filtering Feature
Reduces unwanted noise by shutting off weak transmissions.
Extends the range of your two-way radio by allowing for even weak transmissions to come through.
Allows for the two-way radio to communicate through a local repeater which amplifies your radio signal and lengthens your communication range.
Another set of frequencies that offer better range for factory or office building use. 300 MHz to 3GHz (3,000 MHz)