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Wednesday, September 24, 2014

Covert Communications, by J.K.



 When it all hits the wall, one thing you should be sure of is that someone is listening to every communication you make within reception range. Many will use scanners to try and find you or your group. If they hear radio activity, especially activity on the short-range radios, they will know you are near. Some will use direction-finding antennas to get your exact location. The idea with radio comms is to use the least power and radio with the least range that will get you reliable comms. If all has gone south, you will want to use radio only when necessary, and then keep your conversation short and don’t transmit from your base; do so from a distance, if possible. The first radio suggested is the Trisquare brand. It can be used anytime without being discovered, except by the military if they are looking for you and have radio direction-finding equipment within range, but the chances of that are slim. The Motorola 900 MHz spread spectrum radio is another option, if you have the load of money to buy them, but they really won’t transmit too much further than the Trisquare, as they are all limited on the amount of power they put out. Though out of production, the “Trisquare” radios can still be found for decent prices and are a MUST HAVE. They make two different kinds, both spread spectrum, but I don’t think the lower priced ones will do text messaging. These have up to a three to four mile range over open areas (and sometimes more if high up or less if there are buildings), and they will not transmit to someone over a blocking hill. The great thing about these radios for use within your land, compound, on field operations, or whatever you choose is that the signal is “Spread Spectrum”. This means that outside of very specialized expensive scanners, used close by, no one will ever know you are on the air. The frequency “Hops” or changes thousands of times per minute and is not picked up by scanners or other radios. This way, no regular scanner or other Trisquare radio can hear you unless the Trisquare radio is programmed with the right codes– ones that you make up. The radios can be linked by a common code, so that all can hear your transmission or you can just transmit to one person in a group of radios. They also permit short text messages for total quiet. They operate in the 900 MHz range, so they have short antennas. To modify the antenna is illegal, but if all goes south and there is no rule of law, that does not mean you cannot get “BNC” connector that you can epoxy to where the antenna was after removing it, then buy a gain antenna from one of the many Electronic-Radio antenna distributors with a BNC mount. Get these in advance, and be sure the antenna is made for the 900 MHz band. Don’t modify the radio unless it’s time to get real; if you use a modified radio and get busted doing so, the FCC will fine you a huge chunk of money, so stay legal unless the rule of law goes away. It’s easy to wire the BNC in the radio. Just open the case halves, remove the two wires from the existing antenna, and solder them to the BNC fitting. A slight bit of filing may be required to fit the BNC connector. Then epoxy the BNC fitting to the case of the radio. Motorola also makes frequency hopping radios in the 900 MHz range, but they cost far more money, and others with that type of radio may be able to copy your transmissions. The antennas you will find will be about one foot in length but have 3db to 6db gain. Having 3db doubles the power output, while 6 db doubles the output of a 3db gain antenna; the cost is about $20.00 each. This will enable you to talk and receive further. It is also a good idea to get a regular short standard antenna with a BNC mount for when you do not need the additional range. There are still batteries and chargers, along with 12 V power plugs for the chargers available on Ebay. Several other things can be done for quiet comms. If you use CB radios, turn the antennas horizontal instead of vertical. This causes the signal to be 90 degrees out of phase with all other CB antennas, and it will greatly limit the ability of other CB radios to receive your transmission. Get some H.T. CB radios. These can operate putting out less power. This may limit their useful range, but it also makes them harder for others to hear. For one-way comms in a small area with a regular 5 watt CB radio, buy a 50 ohm “Dummy Load” and put it right outside the window, on the roof with a piece of coax connecting to the radio and dummy load. Dummy loads will radiate your signal for a short distance. Others at any distance will not be able to hear you. Get a dummy load that will take over 5 watts as a 5 watt dummy load will heat up quickly. Keep transmissions short, and let the dummy load cool between uses. You can make your own with a 20 watt, 50 ohm resistor. Just connect the center conductor of the coax to one side of the resistor and the shield that is under the rubber outside to the other end of the resistor.

Another very good form of communication

Consider amateur 2M/70CM HT’s and a mobile radio for long distance transmissions, if you have the money. Getting your FCC Technician license is very easy and will cost you $14.00. You can find dual band (2 meter and 70 CM) radios on Ebay for $40.00. Better quality radios cost more, but the China radios do work well. I prefer the Yaesu FT-60, which cost around $150.00, because they are built like a tank and you can get a battery pack that takes AA batteries. Be sure to get a 12-volt charger adapter for any radio you get and a AA battery pack, if available for your brand of radio. Buy extra battery packs; the higher the capacity, the better. When using these radios, you can go to low power and turn the antennas sideways for short comms, or you can use full power and be able to communicate from 5 to 50 miles if you’re up high and have a direct shot at the other radio. If repeaters are still up and working, you can extend the range to well over 100 miles in many places. Be aware, others will hear your transmissions with these radios from a couple miles to 50 miles away, depending on the power level used and the lay of the land. Flat and open or up high will get you the most distance. Hills, mountains, buildings, and trees will cut down on the distance the radio will be heard. Many of these radios can be set to 1 watt or less. Always use the least amount of power necessary to communicate. Besides others not hearing you, the battery life will be much longer between charges. I would recommend anyone interested in radio to go on to get their General license after their Technician license and obtain H.F. Radios and antennas, both antennas used in fixed locations and portable ones you can string up in a tree. Get the licenses and equipment now so you will gain experience in their use and in building your own antennas. H.F. radios are expensive and do require up to 20 amps of 12 volt power, so having deep cycle batteries and solar panels or a generator and 25 amp power supply (120v to 12V) is a must. With a H.F. radio, when conditions are right, you can transmit all over the world, and most of the time, anywhere in the United States, Canada, and Mexico. Buying your radio used and making your own antenna will save a lot of money. For the most covert use of H.F. radios, you want to make a 40 meter and 80 meter NIVIS antenna. These are just Dipole antennas made from wire that you hang parallel to the ground from a height of 10′ from the ground. Most of the signal goes straight up and has a range of about 300 miles, as it bounces off the ionosphere. It’s harder for someone with direction-finding equipment to find a station using NVIS antennas, but it’s not impossible. The military used to use NVIS antennas to make it harder for them to be found, before going to more advanced systems. Another type of radio is the Murs. These have limited channels and only put out 2 watts. Better to buy the Amateur radios if you want more distance than FRS/GMRS provides. Last, but not least, is the lowly FRS/GMRS radios. Many of you have them, and they can transmit from 1/2 mile to 30 or 40 miles, mountain top to mountain top. However, the combination is FRS/GMRS radios, not just FRS radios, and here is why. FRS transmits with very little power, therefore it has limited range for close in use without being detected. The GMRS radios put out more power for distances of 1 to 3 miles, sometimes less. Again, turning the radios sideways so the antennas are horizontal will cut down on the received range. These radios do have “Privacy Codes”, but anyone can switch around until they find the code you are on, as they all use the same codes and scanners will hear them, coded or not. Switching codes every hour or time you decide will help not being discovered by other FRS/GMRS radio users, but others will scan the codes. It may help but will get you found if others find which code channel you are on. To legally use a GMRS radio, you must get an FCC license at the cost of $75.00. FRS requires no license. The GMRS license covers your entire family. Ebay has sellers who have used Motorola UHF radios that they can program to the GMRS frequencies that put out 25 watts. These are around $100.00. Be sure they program them for you, as it needs special cables and software for programming. You will also need an outside GMRS antenna, and don’t forget, it will be easy to track the higher-powered radio. Expect an 8 to 15 mile range with the antenna at 30′ or better. Most people who have them (the low-power, not higher-power radios) and use them are not licensed, and there is little chance of being caught as long as you’re not causing problems for anyone else. I’ll leave it to you whether to get licensed or not. That said, do not use any other amateur radios, such as the 2 meter/70CM radios or HF radios without being licensed. (The Trisquare radio does not need a license to operate.) There is a good chance of getting in big trouble if caught, and amateur operators do not take kindly to unlicensed operations of amateur radios; they will track you down and report you. When it all goes south, no one is going to use their call signs. So at that point, have at it. One other way to communicate to others close by, once all rule of law is lost, is if the telephone wires in the peds or on the telephone poles are twisted pairs of wire rather than fiber optic. They are there in bundles of wire with different colors of plastic strips wrapped around the bundle and the wires in each bundle being in pairs of blue/white, orange/white, green/white, et cetera. If you buy the military-type phones, you can connect the same colored pair from the same bundle to two or more different houses, then cut the wires on either side of the furthest connection point. You’ll need battery power for the phones. Voltage the phone uses may vary, but the telephone company uses 48V DC for the talk and low amperage AC for the ringers; military-style phones have cranks to make the other phone ring by producing ringing voltage on the line to the other phone and batteries to give talk power. This only works along a run of cable, until it comes to a cross connect box. At that point, you would have to tone out the wires, find the tone from both ends and connect the two with a jumper. If you know anyone who works or has worked for the telephone company, they will know how to hook things up. In many urban areas and cities, they use fiber optic rather than wire, except for maybe a run of cable along the street. A run of cable is all you need for close by homes. Distant homes will not be able to use this system. You will need to have someone who knows how the wires go and is able to tone and connect the right wires. You can also run your own pair of wires between homes. This brings up the last big thing– POWER. You will want to have a way to keep the batteries charged in your radios. For this, you will need something that will charge 12 volts with an adapter or 120 volts without the adapter for the charger. Solar panels with a charge controller and deep cycle batteries are the best way to go. A generator is also good with a battery charger, but you will run short of fuel in time. Wind generators cause noise and are quite easy to spot at height, which is not the best choice in most places. If you have a stream or river with a drop, there are hydro generators that work well. Most radios take battery packs of rechargeable batteries. Buy a bunch. The Trisquare and FRS/GMRS packs don’t cost much, so buy a lot and keep them charged from time to time. Don’t let them go dead. You will also need lots of AA batteries. Buy both large packs of non rechargeable and a lot of rechargeable AA batteries. Along with this, get at least four to six solar battery chargers and 12 volt chargers for the AA batteries. Buy quality rechargeable batteries; the cheap ones go bad too quickly. The HF radios need 12 volts, so deep cycle batteries are the way to power these. When buying solar panels, buy big ones. It’s far cheaper than buying many smaller ones, and you’ll need all the charging power you can get. Buy two to four 120 watt panels at a minimum. I got 120 amp panels from Ebay for $129.95 each, shipped. (The current price is closer to $150.00, which is still a great deal.) Also, buy a few 10-watt or 20-watt panels as back up or for use in the field; the smaller the panel, the more you will pay per watt. Buy a book on solar power to learn how to correctly hook them up. Don’t build your own panels; they go bad very quickly unless built like commercial panels, and they will not be any cheaper if made right. They make 16 watt roll up panels that can be taken in the field to charge batteries when not near your home or camp. Have at least four full-size deep cycle batteries. You can get them in 12 volts or buy Golf Cart batteries, which are 6 volts; just wire them in parallel to get 12 volts. The big box stores have both types for good prices. If you can find a battery supplier who will sell you deep cycle batteries dry, they will not go bad in storage. You just have to buy enough battery acid to fill them; then give them a good hard charge, and you’ll have good batteries long after the old ones have all gone bad. Keep your deep cycle batteries charging on the specialized trickle chargers that monitor battery condition, and be sure to keep the acid level up with distilled water only. Don’t use an inexpensive/cheap charger; they will ruin your batteries. If you become a radio Amateur with at least a General license, you will discover other ways to communicate, such as digital. With digital, no one but another person with the right ham equipment will be able to copy your transmission, but it will be copied on a scanner and a bunch of sounds, letting others know you may be close. You can also do dish to dish, point to point comms, using old computer routers and some other things for a distance of up to 20 miles. Becoming a Ham radio operator, you will learn much about different ways to communicate through some study and the help of experienced operators.

Two other pieces of equipment to have, if possible.

It is good to have a scanner that has what is called near field reception. This means it will pick up and lock on any frequency within its range. there is no need to have every frequency programmed into it. This way you’ll know if others with radios are getting close and can gather intel. Last, a good portable shortwave receiver is handy. I recommend the Sony ICF-SW7600R (Editor’s note: The ICF-SW7600R has been discontinued.) It is small in size, has great sensitivity, great quality, operates on four AA batteries, and (best of all) it can pick up the H.F. transmissions from amateur radio operators as well as regular short wave stations run by governments (if any are left). Most other short wave receivers will not be able to hear the amateur operators, which is where you will get the best and real information. It’s not cheap at about $160.00, but it is the lowest price radio that will allow you to hear amateur HF radio. If you cannot afford the Sony, at least get a standard short wave radio. I hope this gives many of you some good ideas. Communication will prove to be vital when the way of world as we know it no longer exists.

Keep your powder dry. God Bless.

 

From the Survivor Blog

 

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