Ham Radio or CB Radio
License practice quiz https://myoffroadradio.com/courses/online-ham-radio-technician-license-class/
Study Guides: http://www.w5yi.org/
More Practice Tests: https://www.qrz.com/
Here are some things to look for in a mobile ham radio for 4-wheeling:
Dual band feature (2 m / 70 cm) - access any repeaters as you travel regardless if they are 2 meter or 70 centimeters.
High output wattage - nice to have extra power to reach a remote repeater. There seems to be a tradeoff between power and dual band. Most single band 2 meter radios have more output power.
Large memory capability - pre plan the repeaters for a long expedition and have room to store them all
Easy to read display - size, contrast, back light, for driving safety and ease of use
Removable control head - increases mounting options in the vehicle. The bulk of the radio and can go under a seat or in the trunk.
Sealed radio - the cooling fan should not pull air (and, therefore dust) through the radio.
NOAA weather alert - important to keep an eye on the weather when off road.
Cross band repeater function - see above
Ease of use. This is a bit relative. Today’s radios have so many functions, they can be challenging to program the first time. Another reason to get yourself a mentor (known as an Elmer).
Family Radio Service (FRS) is a low power, short range, radio system. FRS walkie talkies are known as “bubble pack radios” because they are sold cheaply in the hang tab shelves of stores or in the toy section. They can be found nearly everywhere on the planet now, and are some of the most ubiquitous radio communication devices in the world. FRS radios are limited to a half-watt of output power (500 milliWatts) and have permanently attached antennas, preventing the addition of an external gain antenna. So, the normal range of FRS walkie talkies in a suburban environment is about a mile or less. FRS Frequencies are FM simplex, 7 channels at 462 MHz and 7 channels at 467 MHz in the UHF band. These channels are in between the GMRS frequencies. GMRS radios may also include FRS channels. The default PL tone for FRS is 67.0 Hz. It is also known as Privacy tone #1, or PL XZ, or Sub-channel CTCSS 01.
General Mobile Radio Service (GMRS) is a local distance radio system in the same UHF band as FRS. GMRS radios can be capable of longer distance range and greater dependability than FRS. GMRS is becoming more popular as bubble pack walkie talkies (HT) include both GMRS and FRS channels. GMRS-specific frequencies are FM simplex or duplex with 8 channels at 462 MHz and 8 channels at 467 MHz in the UHF band. The maximum power level of a GMRS is limited to 50 Watts. The most common GMRS mobile, base, or repeater radios use external gain antennas. GMRS walkie talkie handheld transceivers (HT) have only 5 Watts or less, commonly with a ducky antenna. Full duplex repeaters can be used with GMRS. GMRS Repeaters have their input channel at 467 MHz, and their output at 462 MHz. The offset is exactly 5 MHz. For repeater use, the field units transmit on 467 Mhz and receive on 462 MHz. Most bubble pack GMRS radios are simplex-only, so they do not function through a repeater. They operate only on the repeater output frequency (GMRS Channels 15 through 22). The default PL tone for GMRS simplex is 67.0 Hz. It is also known as Privacy tone #1, or PL XZ, or Sub-channel CTCSS 01. In a GMRS radio, the GMRS channel number is often the same for simplex and duplex, but a secondary (programmable) feature of the channel controls whether it transmits duplex +5MHz split or simplex. The GMRS simplex and duplex (repeater) channels are included in this list and programming file. In the Channel Name, they are programmed and identified separately; the repeater channel has an R in the channel name. For example as GMR 20 is the simplex channel, and GMR20R is the repeater duplex channel. PL tones vary among different repeaters in various geographic areas. The default PL tone for GMRS repeater channels is 141.3 Hz, but it can be changed in the user’s radio programming to another PL tone frequency as required to hit specific repeaters.
Personal Mobile Radio (PMR or PMR446) is a low power, short range, radio system similar to FRS. It is very common in Europe, Africa, and Asia. Walkie talkie bubble pack PMR radios are sold cheaply. PMR radios are limited to a half-watt of output power (500 milliWatts). So, the normal range of PMR walkie talkies in a suburban environment is about a mile or less. PMR frequencies are commonly FM simplex, 8 channels at 446 MHz in the UHF band. An additional 14 digital channels are available for PMR446, but are less common. In USA and many other places, the 446 MHz band is assigned to Amateur Radio Service (Ham) so, all the PMR channels can be used by hams in those areas. The default PL tone for PMR is 67.0 Hz. It is also known as Privacy tone #1, or PL XZ, or Sub-channel CTCSS 01. The PMR Prepper channel (PMR 3) (446.03125 MHz) is somewhat interoperable with the Ham UHF Prepper channel (HAM U3) (446.030 MHz).
Amateur Radio Service, widely known as Ham Radio, is an internationally allocated radio service for non-commercial radio communications. It has frequency bands in all areas of the spectrum. The ham radio frequencies in this list are only a few of the most common VHF and UHF channels used by ham operators for local FM simplex. Additionally the list includes the Prepper Ham VHF simplex channel (146.420 MHz), the Survivalist Ham VHF simplex channel (144.550 MHz) and the Prepper Ham UHF simplex channel (446.030 MHz) that is somewhat interoperable with the PMR Prepper channel 3 (446.03125 MHz). The default PL tone for Ham is 100.0 Hz. It is also known as Privacy tone #12, or PL 1Z, or Sub-channel CTCSS 12. Most hams also make use of repeaters in the VHF and UHF bands, but the channels for these repeaters vary according to geographic area. There is no universal repeater channel frequency or PL tone that is valid in all areas, they are all different. When programming your radio, it is advisable to include the repeater channels and PL tones in your area. See a repeater directory for more information.
Marine radio service in this list includes the most common simplex VHF channels in use by boats and ships, for inter-ship and safety communications by FM voice. Marine VHF radio is used on the high seas, inland waterways, lakes, and rivers by vessels and shore stations. No PL tone is used by Marine VHF radios, it is all carrier squelch. The Marine channels have the transmit PL tone turned off, and use Receive Carrier Squelch. Most Marine VHF radios also have duplex channels for use when communicating with shore radiotelephone and port operations. The duplex channels are purposely not included in this list, in order to keep the total number of channels below 99.
Business radio, or commercial VHF and UHF radio channels, are generally set up for specific companies in a local geographic area. There are also a few business radio channels, called Business Itinerant, that are devoted to operation anywhere. These are low power simplex channels, and only 2 of them are included in this list. The Red Dot (151.625 MHz) and the Purple Dot (151.955 MHz) channels are common Business Itinerant channels, and they are some of the most popularly used channels on VHF for commercial or rental HT walkie talkies. The default PL tone for the Business channels is 67.0 Hz. It is also known as Privacy tone #1, or PL XZ, or Sub-channel CTCSS 01.
For EMERGENCY ONLY, SAR is a service channel for Search and Rescue (SAR) or Emergency Medical Technicians (EMT) . The primary interoperability channel in USA for SAR is 155.160 MHz FM simplex. This is a very important channel to keep clear for emergency purposes, and should never be transmitted on for non-emergency communications! The purpose is to provide mobile, HT, and base communications for field operations of land or ground search and rescue teams, ambulances, and medical personnel at the scene of incidents. It is identified in the list as the channel name SAREMT. The default interoperability PL tone for SAR EMT is 127.3 Hz. It is also known as Privacy tone #19, or PL 3A, or Sub-channel CTCSS 19.