team radio selection
March 23, 2014 at 10:22 am #96796Ronald BealParticipant
Just sticking with small team tactical comms, I am going to limit my post to 2-way voice communications in a small handheld or manpack format.
This is just a brief introduction to the different types of radios…. whole books can be written on each category, I am just trying to keep it distilled to the basics.
Typically, in the U.S. we can categorize radios by the FCC licensing/ part that regulates the radio.
Citizens Band Radio aka: CB: no license required, 40 channels around 27Mhz (am)… 4 watt output limit (12 watt SSB)
Pros: inexpensive, available at any truckstop in the U.S. Lots of accessories, Some vehicle units also do SSB, which allows longer ranges
Cons: efficient antennas tend to be on the long side for handhelds, and because they are ubiquitous, lots of potential for others to snoop on your comms
FRS/GMRS: The ubiquitous bubble pack radio, can be found at Wal-Mart, Radio Shack, Best-Buy, and many other places
FRS refers to the “family radio service”, and GMRS refers to the “general mobile radio service”…. most of the new radios include both FRS and GMRS frequencies, however there are slightly different specs and requirements to use the different radio services
FRS: no license required, limited to 1/2 watt from a permanently attached antenna. 462-467Mhz(fm)
GMRS: FCC License required… $85 for 5 years, good for all of your immediate family. GMRS shares some of the same frequencies as FRS, and when operated from a FRS/GMRS radio, has the same 1/2 watt, fixed antenna restrictions as FRS. When used on GMRS only equipment, GMRS is limited to 50 watts, and repeaters can also be used.
Pros: Small, ubiquitous, inexpensive
Cons: Limited range (1 mile at best despite what the label on the box says), and again, because they are ubiquitous, it is easy for others to snoop on your comms.
Some frequencies are not legal to use along the U.S. Canadian border.
Multi Use Radio Service aka MURS: No License required. Originally set up as a set of frequencies for drive way intercoms systems. Only FCC accepted Type 95 radios are legal for use on these 5 frequencies starting at 151mhz fm (Technically type 90 radios certified before 2002, with a 2 watt limit can also be used)
Pros: Not common, so some security through obscurity. Many drive way motion sensors also transmit on these frequencies, so you can use those motion sensors as intrusion detection, and not need another piece of hardware to monitor.
Cons: Only 5 channels, not a lot of gear choices
Marine VHF Radio: License required… Legally, only boat to boat, or boat to licensed land station allowed. Some folks do use marine VHF for backwoods comms, but it can be heavily monitored by the coast guard. And getting caught can mean fines and having your equipment confiscated.
Pros: Lots of choices and availability
Cons: because generally not legal, can be difficult to test and practice with systems.
(I personally recommend staying from Marine VHF for team comms)
Amateur Radio: License required, test is usually about $15, different levels of license, good for 10 years, renewal free. Many frequencies/bands/modes available
Anyone using the amateur bands must be licensed. FCC callsigns must be used regularly, no encryption allowed. For small team comms, the VHF, and UHF handhelds, and vehicle units excel. Handheld typically 1-5 watts, vehicle 50-100 watts…. limited to 1500 watts (but much over 100w is usually a waste of money and electricity)
Pros: Greatest variety of equipment available, also the most powerful and flexible
Cons: legal I.D.’s and a large self policing community make coded/encrypted comms difficult. Having your call tied to a searchable database means anyone that hears you can locate your mailing address.
Business band radio/Public safety: All requires FCC licensing, high variances in cost based on number of transmitters, frequencies, number of frequencies, region, etc. These radios are used in everything from hospitals to hotels, large warehouses, public safety departments, movie sets, taxi cabs, etc.
While the most difficult to license, these radios have the largest variety of equipment and options available. Encryption is sometimes an option, as well as digital.
Pros: often heavy duty radios, with lots of choice…. digital or encryption can improve comsec
Cons: expensive, resource intensive to get started.
Milsurp radios: You can find tons of military surplus radios on sites like Ebay… Generally these suck for modern team coms.
Pre SINGCARS radios are usually 30mhz-80mhz, which means you only have 5 frequencies on the 6m amateur band to legally use them (assuming you have an amatuer license) PRC-6, PRC-8, PRC-9, PRC-10, PRC-25, PRC-77 etc… These radios are heavy and limited for what they do. SINGCARS radios… if you find one that is functioning, you are still limited to the few 6m frequencies in SINGCARS single channel mode. The frequency hopping functios are not legal for frequencies you could legally use the radio for, and for the most part, civilian possession of the equipment required to generate, copy, and load the frequency hopping tables, is illegal (those are CCI: Controled Cryptographic Items)
In short… expensive, limited, and heavy. Not very good team radios
Other: ISM, SMR:
There are other categories of radios that fall under specific rule sets. ISM: Industrial, Scientific, Medical. SMR: Specialized Mobile Radio.
Typically radios in these classes do not require a license, and are limited to 1 watt. ISM has lots of “stuff” sharing its frequencies. WiFi, wireless security cameras, cordless phones, baby monitors, etc. A few companies have built dedicated radios that fall under the ISM band, notably the now defunct TriSquare eXRS radios, and Motorola MOTOTRBO. Because there are few requirements for the type of transmissions in the ISM band, each mfg came up with their own format…. most radios are spread spectrum (kind of like frequency hopping), digital, and thus very hard to snoop on. The Nextel Direct Connect phones listed above, while on the SMR band, are functionally like most ISM radio systems.
Pros: very secure
Cons: can be expensive, only work with equipment from same mfg.
I’m sure I have missed a few typos, or got a minor detail wrong above…
Feel free to correct any errors,
and hope it helps
March 23, 2014 at 11:13 am #96797CorvetteParticipant
I learned something.
March 25, 2014 at 10:09 pm #96798MaxKeymaster
Awesome post. Do you have a recommendation for a man packable (smaller the better) HF capable radio? Thank you!
March 25, 2014 at 11:51 pm #96799Ronald BealParticipant
If you have the money.. .I would recommend the Elecraft KX3, with the 2m and tuner options.
More affordable options would be the Yaesu 857D, 897D, or 817ND.
Depends a lot on your budget, experience, and technical requirements.
The KX3 is the most flexible, The 897 is all in one. The 857 is the same guts as the 897, but in a mobile format, so battery will be external, and the 817 is a lower power (and slightly simpler internal electronics) version of the 857.
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