Disclaimer: I am not a lawyer! Nor am I a communications specialist. Nor am I an electrical engineer. All of the values cited in the following letter are estimates, and anyone is invited to refute or embellish, or add corrected information to these meanderings. I am by no means an expert on the subject, but, I do have some background in amateur radio and have been involved in communications since I built my first "comm" system at the age of 14 for myself and my buddies, and throughout the years, including time spent in the US Army Signal Corps and as a holder of an a U.S. Amateur ("Ham") license. Any information included in this dissertation is my own opinion, and I will not be held responsible for anyone taking any part of it out of context or using my interpretations as advice for any illegal purpose. And, as always, your mileage may vary. I also won't get into propagation characteristics of each band, except in a personal experience sort of way. That would be a book unto itself.
I have noticed a lot of disinformation regarding so called "survival communications". Let's talk about the interpretation and my opinion of some the legalities and the pitfalls of the most bandied-about schemes.
I am starting with my hard wired comm scheme between my parents house, and my buddy's houses back in the early 1960s; conjured together with parts reclaimed from the dumpster at the Western Electric factory where they built those really neat rotary dial phones:.
1] Price, free, except for sending my little sister and brothers dumpster diving. I had to pay them in nickel candy bars.
2] Secure, no doubt, hard wired. Well, unless you count line taps.
3] Risks? One of the neighbors kept cutting the wire in the storm drain.
So, hard wired is the most secure, unless the aforementioned line taps are applied. A good current detection device will clue you in to voltage drops due to line taps. This schema is also the most susceptible to interruption [from cut cables.]
Yep, legally, you are allowed to send and receive voice communication within the Multiple Use Radio Service (MURS), at a grand total of 2 watts out from the radio. Depending on the gain from your antenna system, your line losses from cable and connectors, and your distance to your intended recipient, this may be a option for your network. On the other hand, I am sure some of you have gotten the bright idea of buying some of the VHF Ham gear out there, and made the conversion so easily done to these rigs, and now have anywhere from 65 to 100 watts of power available for use on these MURS frequencies! The most unfortunate aspect of this is: look where the MURS frequencies reside: smack dab in the middle of the Public Service band. I would hate to think what would occur if someone started broadcasting with that amount of power, a few kilocycles away from a fire department or police channel. You are in for a lot of grief if you are caught. So, to be legal within the MURS band, you really need to have a most efficient antenna system with just 2 watts kicking into it. Let's think a nice gain beam [antenna]. Use Belden 9913 low loss cable, [which has only] about 1.5 to 2 db loss per 100 feet, nice UHF connectors, the newer ones with maybe 1.5 db loss each. And as each 3db gain yields, in theory, a doubling of output power. And you can pretty much have an effective radiated power [ERP] of between 10-to-20 watts or more from a 2 watt radio, depending, of course on the gain of your antenna. Not bad. And depending on distance and your intended use, this may provide your network with suitable communication for your intended purpose.
or low power broadcasting, is nothing to be laughed at. We used to establish
across the US with 20 watt radios during good propagation periods with VHF
equipment and some killer homemade beam antennas on top of the tallest peak
in the state. I guess the best one I built was, in theory, around 15-16 db
I used simple parts available most anywhere wire, cable and hardware is sold.
I think one of my better ones I built for 2 Meters/440 dual banding was hacked
out of an old television antenna.
1] Price? You can do it on the cheap. But I really suggest investing in a good SWR [Standing Wave Ratio] meter as one of your first purchases. And be sure to get radios that allow the use of external antennas! Once you start tuning your system, you will be surprised at the difference a finely tuned antenna system will provide.
2] Secure? Pretty much. Not a lot of folks using MURS, at least in my neck of the woods. I have a scanner going when I am home, and I have never heard anyone using these frequencies. Again, YMMV.
3] Risks? Only risk you take is not following the legal output limits and risking the ire of the local public services, and indirectly, the FCC. If you do it legal, no worries. With the exception of falling off the roof or hanging your antenna on power lines, or falling off the tower. You get the picture. But if you hack a "big radio" and have a lot of losses in your antenna system, which leads to a lot of garbage being spewed from your system, which really ticks off the fire and police services in your area, as well as eventually damaging your rig. And when the FCC gets involved, your low profile is shot to pieces! The FCC doesn't play. You can read the reports on the web [Typically,] you get a warning the first time; the second time, you get fined--usually around $10 ,000. The reason I proffer this advice is that I have seen a few remarks on the web about this very same subject. Don't take the chance of screwing up your life just for communications. There are plenty of legal avenues which allow you to accomplish your goals.
This is a wonderful country, is it not? Do you think other countries give it's populace the right to communicate so freely? Not many.
1] Price: Varies
2] Secure? You call it. Lots of ears tuned in 24x7
3] Risks? Be aware that all parties must hold a valid Ham license to operate a rig, or be in the same room with a licensed Ham at their side. Don't even think about buying a couple of ham rigs to chat without getting licensed. Forget that the FCC and.the local amateurs will hunt you down. The "fox hunt" that will ensue will be an "event", complete with barbecue, door prizes, and direction finding gear! Those old boys have worked long and hard to keep [their portion of] the spectrum. They are not about to let a couple of fools screw it up for them.
But, if you and your crew want to get the Technician/General amateur license,
it is very easy with the "no-code" requirement now. Or even learn
the code [talk about secure!] It is a remarkable hobby filled with good folks
storehouse of information is amassed among all those good folks. Allowed output
power is awesome, plenty of inexpensive gear to utilize. This may be an option
for you. But, as mentioned, the Hams police their own freqs and rightly
so. They have been fighting off interlopers for years. Do it legally. Ii is
very rewarding. [JWR Adds: It is noteworthy that the advent
of the Internet has meant a decline in amateur radio usage. Web surfing and
many of the hours that hams previously used on the air. A lot of middle age
hams are letting their licenses lapse. This means two things: 1.) Plenty of
in the erstwhile "crowded" bands, and 2.) Lots
of high quality used ham gear available at ham fests and swap meets for
pennies on the dollar. I strongly encourage SurvivalBlog readers to
get their "No Code"
1] Price: expensive! This applies to all Business Band equipment. And the following is my interpretation of the FCC regs. I am not a lawyer. I have just pored over the convoluted FCC regulations so many times, that this is what I have determined: If you want to correct me, please be my guest! The legalese is tremendous within the regulations. The print is so darned fine, I had to use a magnifier most of the time to read it [grin] So, here we go. This is how I understand it:
If you are not a HAM, [and many hold the $85, five year GMRS license as well as their Ham license] by law, you cannot convert a Ham 440 rig to operate in the GMRS band. A Ham is a hobbyist and the Amateur Radio Service was started as a hobbyist and experimental environment. If someone holds a valid Ham license, and a GMRS license, they can use their UHF440 rigs to operate within the GMRS and FRS services, within the proper output power limits. And vice-versa. In the olden days, Ham conversions of commercial gear to operate in the Ham bands were common. Again, Amateur radio is a hobbyist service, and the rules and regs take this into account. GMRS is strictly a service designed to provide families and family-owned businesses a mode of communication. And as such, is an entirely different animal. There are any number of grandfathered businesses still using these frequencies..they can't interfere with you and you can't interfere with them. Everyone is accountable. You must apply for, pay and receive your station license from the FCC for the General Mobile Radio Service, and use FCC Type Accepted Business Band radios for your communication needs . Be aware,that the FCC can inspect your station at your licensed address, at any time of their choosing. Seriously, I don't think they will ever do so, unless they receive complaints. But, it is a caveat of the licensing structure.
Okey dokey, let's get to the good part: 50 watts! You are allowed to use up to 50 watts out at the radio end of things. You pay your $85, and you have some decent power to play with. Add a nice 10-12 db gain antenna, some low loss cable, and connectors. You get the picture. There is a tremendous [difference in the] amount of effective radiated power [ERP]. If you really want to get geeked out, and adapt/buy/build a nice high gain beam [antenna]. You can see where I am going with this. Several caveats as well with antenna structure, since we are on the subject: height, no more that 60 feet above ground level or 20 feet above the structure that the antenna is mounted on.
Here is another caveat: All GMRS repeaters are the private property of their owners! The owners of said repeaters can allow and deny access as they wish. As a licensed GMRS operator, you can operate simplex on the GMRS frequencies with full power, you can operate at 5 watts out on the interstitial and FRS freqs, but you must have permission or an agreement to utilize someone else's GMRS repeater. This doesn't mean you can't put up your own repeater on an unused GMRS assigned frequency pair.
Bubble Pack/Blister pack FRS/GMRS Handi-talkies (HTs) are commonplace. They have limited battery life. Did I mention that most are illegal [if operated on the GMRS band without a license]? The FCC seems to ignore these toys mainly because of their low output and limited ability to cause problems with existing services. They probably also feel it is poor form to arrest a 10 year old just because he is operating a walkie-talkie without a license It is also illegal to modify the unit to add an external antenna to it, and yes if push comes to shove, you can build your own re-transmitter out of a pair of them to retransmit your signal. The legality of that is also suspect, depending on the channel you are utilizing the repeater on. Be aware that the [advertised] "17-to-25" mile units may provide reliable comms in an urban environment of only around three miles! That has been my experience with some of the top of the line models. They are useful , when coupled with a GMRS licensed business band high power rig, to provide simplex communication between family members. As mentioned, GMRS is a service that is designed for the family. You can communicate with other family members or other GMRS license holders, legally. No , you can't hand out blister pack radios to several of your hunting buddies , while you sit back at the cabin giving out your call sign , with 50 watts of juice pouring out the back of your rig! But, You can have any number of families, each with a valid GMRS license, communicating all they want to, with any number of radios, with at least one person in each family a valid GMRS licensee. Think of the possibilities.
2] Secure? Relatively. You can look on the 'Net and see how many licensed GMRS holders there are in your area. Figure that someone may be listening at any one time. Figure that you may hear a lot of kids playing army with them. But, for the most part, at least in my area, not a lot of activity , except for the aforementioned young warriors "taking the hill". Again, if you are legal, you have nothing to worry about. That is one of the positive aspects of the license fee: It keeps most of the folks that are not serious about the proper utilization of the band, off the band. At least, off the band running a lot of power...
3] Risk: Besides the obvious of any person listening to your conversation, and you being well within the letter of the law. None.
Repeater owners. Power [source]! Many repeater owners do have backup power on their repeaters. But, again, you should not rely on other folks for your needs! Build your system so that simplex is your most oft used means of making contact. And power redundancy.
Stay away from the scramblers you see advertised...They are illegal to use on GMRS and those who are caught using them seem to be the kind of folks that drive a large powerboat in the middle of the night from offshore and deliver huge bundles of goods to large trucks parked at the edge of the bays and estuaries on the Florida coast.
1] Price? To do it right, you really need some of the higher end SSB radios, period. Or, if you are really lucky, you can find some of those superb Johnson SSB 23 channel tube sets sitting at a yard sale table brand new in the box! You wish.
At 12 watts Legal output, with the ability to buy or homebrew some really high gain antennas, SSB CBs may be a viable option. For example, if you have the acreage, a Rhombic designed for the 11 Meter band is one killer antenna! Agreed, it is large , but the gain from one of these monsters is around 22-26 db, in theory. I built one for the 10 meter band. There were very few pile-ups [Pile-ups = large number of amateur stations trying to contact a rare station] that I couldn't bust with my 100 watt rig and the rhombic. I gave out a call one morning, from the wilds of Alabama. A fellow from California answered back, asking how much power I was running, since the band wasn't "open" yet! ("Open" meaning propagation that is conducive to reliable communications.) He was running a kilowatt, and, of course , he was making a joke, but, it does point out what can be done with a couple hundred feet of wire and a little bit of power--and a homebrew tuner built with parts from a PRC-25, Vietnam era vintage surplus radio. If you decide to homebrew, think about the Rhombic [antenna] or similar. Lots of miles per gallon with this antenna. Commercial antennas are as pricey as business band, from what I have seen. And yes, you can utilize Ham antennas for peak output in the 11 Meter band. Again, a good SWR meter is a necessity.
2] Secure? In my personal opinion, SSB is extremely secure, at least in my area. I monitor the 11 Meter band along with the rest, when 10 meters is open, I will also cruise thru the 11 Meter band and have yet to even hear anyone on SSB. Except, remember, I was not going to get into propagation characteristics. Well, okay, band openings mean you may be able to chat around the world when conditions are right. Whether that is helpful or a hindrance, you make the decision.
AM (Standard Full Band Propagation CB Channels 1-40): The negative aspect? Every Bozo on the block who ever had delusions of grandeur seems to have spent $40 on a radio. I have yet to find an open channel on AM, well, almost never, I pretty much gave up on it unless it is Channel 19......always seems there is someone either railing against something, sprouting racist nonsense, or simply some drunk singing Hank Williams on a channel or playing local DJ !
Positive aspect? I do carry one in my truck for travel, and for that, Channel 19 is invaluable when commuting. Lot of good folks driving trucks, and a few idiots as well. Ignore the foul mouth idiots, and by all means, install an el cheapo AM CB in [each of] your vehicle[s]. The first time that the truckers notify you of a [traffic] jam and save you an hour sitting in traffic, and not sitting at home, it makes that little bit of coin you spent on the rig well worth it! $40 for the radio, another $20-to-$30 on a mag[netic] mount antenna. These are 4 watt radios, and the commercial mag mounts antennas are pretty much 3 db gain...so, they compensate for the line loss and what little reflected power there is since they are tuned for center band. Channel 19!
Risks: As far as licensing, none. As far as interference to other persons, possibly plenty! The 11 Meter band has been known as a major noise maker for relatively cheap, less than adequately shielded electrical devices. And with the influx of even cheaper import electronics, I doubt the shielding has gotten any better. They are supposed to adhere to FCC design specs. Only thing you can do is provide the best possible antenna system, with the lowest losses, and see what transpires with the video and audio devices in your home and adjacent homes. In the "olden days" you could buy/build filters to install on you and your neighbors sets to alleviate most if not all interference. But, unless you have really good relationships with your neighbors, I believe you may be rebuffed when you try to play with their home theater! Then again, interference may not be a problem. I do know if you decide to be a smart guy, and drive an amplifier with your rig, and you do cause interference, and it is reported, and you ignore the warnings from the FCC, they will prosecute.
Equipment: In my opinion, start cheap with the transceivers unless you are sure that the system you have chosen will be viable. If you are guessing, then buy used, with 90 day warranties, from a local dealer if possible. Ask their opinion, get their help if needed. Most are glad to assist, since they like to sell equipment!
Buy the best antenna components possible: Belden 9913, Top Quality UHF connectors or Type N connectors as I use on 400 MHZ and above. Yes, they are expensive. Don't get cheap on your transmission system. You don't put cheap tires on a vehicle that your wife and kids depend on to take them places. The car may be old, but you are a fool to ride on old rubber. Same with your comm system: the radios may be used , ugly and perfectly functional, and 1/2 the cost of new, but invest in the very best transmission line components that you can. Please get yourself a nice SWR meter! Also, be aware that this gear has resale kids. Just look on eBay. Distance between "stations" and terrain will be the determining factor in 90 percent of your communication schema. And , in most cases, the only way you will be able to find out is to experiment. So, you invest in a system to test the waters..you find it just doesn't suit you or your group's needs....you can usually get the majority of your funds back, and continue on to the next investigative venture! So you lost a few bucks. You gained knowledge and experience, and hopefully another skill to add to your resume. I actually get a great sense of accomplishment putting all the pieces together and making a system such as the ones described function as they should. Sure beats sitting in front of a computer blasting bad guys with lasers. The 'Net is a storehouse of information...if you want to homebrew some of this stuff, there are plenty of resources at your local library, Ham clubs in your area, the 'Net, as mentioned, and you may have friends or relatives already "in the know" who would be glad to assist.
This is by no means a comprehensive analysis! Just a few thoughts on the subject. Stay on the right side of the FCC, don't fall off the roof, keep your antennas away from power lines, and above all, have fun!
- Bob in Georgia
JWR Adds: I second Bob's motion on his suggestion "don't get cheap on your transmission system". Buy (or build) good quality antennas, and buy top-of-the-line connectors and the best coaxial cable you can afford. Also, don't forget that any coax that is exposed to the elements should be changed once every 8 to 10 years. (Or even more frequently in extremely humid climates, or in locales with big temperature swings.) So, if possible, lay in a supply of extra coax. (Look for reels of it at ham swap meets.)
Disclaimer: Anyone that is planning to use any radio transceiver system should research applicable laws and get the appropriate licenses before ever buying equipment or keying a handset!