The Comfortable Pocket Yacht 
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Flicka Sailing
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Photographs Why Consider On Board Single Sideband Radio (SSB) I have made a promise to the various family members and friends to remain in touch via eMail - even when I'm out sailing. Now my problem is how to keep this promise without breaking the bank on communication equipment and services. For the near future, I believe that Amateur SSB radio communication is the best way to go. With SSB, I can communicate over a range of several thousand miles and this will clearly meet my needs. SSB radio for eMail requires several major items of equipment - and all of them need to be as small as possible.
The guiding principle for equipment selection must include low cost, small size and low power consumption. As a guess, a new commercial marine SSB installation with the hardware required for eMail (not including the laptop computer) will cost around $3,500 plus installation ($1,000 to $1,500 generally). The commercial service contract will also have an operating cost of about $450 or more per year depending on how much you use the eMail. By getting an Amateur Radio License, I hope to get this down to about $1,500 or less going the route of used amateur radio equipment - an added benefit is that there would be no significant operating costs and I will do my own installation which will save significantly.
In 1999, AT&T closed their Public Coast Radio Stations since they claimed that their continued operation was too costly and that other means of offshore communication such as satellite were available. For the commercial marine segment (and private individuals with Fat Wallets), this is clearly true. However, for the little guy, SSB is still a very good option. As of now, there are still several smaller commercial Public Coast Stations in operation - the majority of which provide only SSB eMail service. If the sailor needs to send business related eMail, then this type of SSB is the only option since Amateur Radio is forbidden to transmit business related messages. Also, if obtaining an amateur Radio General Class License is not possible, then this is the only way to go. The advantage to the commercial option is that you pay for a service and have a choice of providers (even if the list is small). Also, the Marine Operator's Permit and Station License that is required do not require technical tests to be passed. Since the operator permits are universally recognized, no special requirements exist when crossing international borders. The main disadvantage of the commercial route is the limited selection and higher cost of the FCC Type Accepted radios that are required to operate in the Marine frequencies. Even in the used market, these radios can cost two times the amount of an equivalent Amateur radio. In addition, there are some significant fees associated with Commercial eMail services - both annual contracts (about $30 to$40 per month with a one year minimum contract) and additional usage based fees that can range up to $1.00 per message unit. In this case a message unit is defined the smaller of one message or a block of 1000 characters (including control characters). This means that a two page letter via eMail will cost $2. Even with limited uage, this can add up to a fair chunk of change. In order to participate in Amateur Radio, a valid FCC license is required. On December 30, 1999 the FCC announced a major restructuring of the License requirements. Under the new rules scheduled for implementation on April 15, 2000, a General Class License will still be required for access to the frequencies in common use for long distance eMail. Under the new rules, this License will require passing two written exams on rules, theory, practice, and safety of radio operation. In addition, knowledge of Morse code is required and the operator must be able to send and receive at a speed of 5 words per minute (25 characters per minute). Passing the written tests should require some study with a few good books since all of the possible questions on the test will be published for anyone to review - the Morse Code test will require more concentrated study with one of the many Morse Code Tutor programs available on computer. Amateur radio is composed of a universe of dedicated hobbyists - many of whom also are sailors or pursue other mobile recreational activities. In response, a network of Amateur stations have been established to provide gateways between the world of Radio and Internet based eMail. These are not commercial activities and the stations will come and go as time and the operator's interests dictate. However, there seems to be enough interest in this activity to assure some degree of connectivity for the near future. From an equipment standpoint, there are several manufacturers and a steady supply of relatively modern and less expensive used equipment on the market. However, Amateur Radio is licensed by each country and as an amateur operator crosses international borders, a new temporary operating permit application will be required in each country with a generally small fee being paid. In the Bahamas for example, the fee is $6.00 - the permit is usually issued within a week or two and is valid for a period of one year. In Canada, no application is required but in Mexico, an application is required and processing may take more than one month while the permit is only valid for six months in total (including procesing time). In other words, plan in advance! My plan is to be in line as soon as the new rules go into effect and pass the examinations required to get my General Class License. In the mean time, I will continue to scout the auction sites and Ham swap meets for the equipment I require. Due to the transition plan between the old and new rules, I may take some of the examinations under the old rules in order to get a jump on the requirements. Commercial Marine Radio Equipment In order to use a SSB radio for Marine use, it must be type accepted by the FCC. As of now, this limits the market to companies such as Icom, SGC, and SEA. There are other high end providers but their equipment is out of sight for all but the large commercial vessels. Some of these manufacturers also provide dual purpose units that are capable of both Marine and Amateur service. In this capacity, they are really Marine radios that can transmit out of their assigned bands into the amateur frequencies - they are no where near as flexible in their operation as most Amateur Radio operators would like to see. From what I have seen, the most desirable Marine radio would be the Icom M700-PRO model or the similar ICOM 710. These models are available from West Marine and most other marine suppliers at a cost of about $1,100 to $1,600. A matching antenna tuner (Icom AT130 ) is also required and sells for about $500
There are a significant number of companies producing Amateur Radio equipment for the 2 million or so amateur Radio Operators worldwide. With a relatively large market, there is also a significant amount of used equipment available so this might allow cost cutting. Since a driving force behind my requirements is to have eMail on my sailboat, I will need to concentrate on more modern equipment designed for low power consumption and digital transmission capability. One additional requirement is that the receiver be general coverage so that receipt of SSB Weather Charts is possible. For those interested in listening to the international broadcast frequencies, the older Amateur radio tranceivers supported AM reception which is sometimes easier to use than trying to tune an AM signal with an SSB receiver. My first amateur radio consisted of an ICOM 735 purchased used. This worked well but was physically large and consumed more power than I would have liked to use. At it's minimum settings, the unit transmitted at 10 watts and I found that this was more than I needed. I then went looking at alternatives and now, my station consists of an Elecraft K2 transceiver with the internal SSB module and antenna tuner options installed. The Elecraft K2 was selected due to it's low power consumption and high quality receiver functions. This radio is only available in kit form from the manufacturer but the process of building the radio is well documented. It took me about two and one half weeks to complete - and that was while living aboard the boat. Conventional wisdom says that you need 100 watts of power to communicate via SSB - NOT TRUE. I have never had a problem exchanging email with land based stations using only the 5 watts that the K2 supports in digital modes. In fact, I have been successful with less than 2 watts over a range in excess of 1,000 miles.
With respect to the Radio Modem, the top of the line is the Pactor II from SCS. At a price of about $1,000, this would not be a realistic selection for my purposes. Even the Pactor IIe economy model sells for almost $650 and is too new to be found on the used market. Since money is tight, I should start with older technology such as the Kantronics KAM Plus or AEA PK232. With upgrades available from the manufacturer, these units support the Pactor I but not Pactor II protocol. Ebay seems to offer a number of these at any point in time but the price of a used unit with the additional costs of upgrading to the current version firmware will bring the total to $250 or more. Also, even with the upgrade, these units are still only capable of Pactor I operation and not the much more efficient Pactor II. Furthermore, the software of choice for eMail over amateur radio does not support all brands of modem so this will impose additional limitations. It seems to me that efficiency is the killer in this equation. I really don't want to spend the money for the Pactor IIe unit, but since it operates about 5 times faster than any modem using Pactor I, I really don't have much choice. The electricity supply on a small boat operating off a solar panel system is the deciding factor, if I can cut down on electricity consumption with a better modem, this is the best solution despite the higher initial outlay from my coin collection.. I will not minimize the complexity of this operation. Getting an Amateur Radio, a Radio Modem, and a laptop computer to operate together is not "Plug and Play" - it is not an easy task - and then it must still be able to communicate with a similar setup several hundreds of miles away. This will take time and effort to establish the connectivity. I followed the hardware installation recommendations given on the Airmail 2000 software site - including the use of clip on ferrite chokes on all interconnecting lines (radio, radio modem, and laptop computer) A sailor can have the most expensive SSB radio, the best Radio Modem, and the best Laptop computer to connect them for digital communication and still not be able to communicate across the anchorage or out of shouting range if the antenna system is poorly designed. I have no intention of going into antenna theory here - I just want to describe the options I have considered and then describe my starting point. Conventional wisdom says that a good SSB antenna on a sailboat is VERY difficult and EXPENSIVE to install. The experts will ramble on at great length about the requirements for a counterpoise (ground plane), the cost of backstay insulators, special weatherproof automatic antenna tuners, and special cables to join the various pieces. The experts are absolutely correct - but only if you want access to SSB transmission at any and all frequencies both at anchor and while under way. However, if you only want to use SSB transmission every few days while at anchor - is it still difficult and expensive - NO!!! The Expert's Antenna Choice for a Sailboat There are several commonly used antenna configurations for a sailboat - most users install an insulated backstay for their antenna with some others installing a vertical whip (23 feet tall minimum). In either case, the major factor that determines good long distance operation will be the installation of a very high quality ground plane (also called a counterpoise) for the antenna. These antenna types also require a sophisticated (and very expensive) antenna tuner to operate correctly. For either of the above antennas to operate on the many different frequencies of the Marine and Amateur services, the antenna must be at least 23 feet long and the antenna tuner must be connected to a ground system composed of copper foil radials that are as long as possible and have as much surface area as possible. Some experts suggest that a minimum of 100 square feet of copper foil is necessary for good operation with a backstay or vertical whip. One thing is essential and that is to keep the antenna tuner as close to the antenna and the ground plane connections as possible (no more than 3 feet). If copper foil ground planes are to be constructed, the recommendation is to make each of them at least 20 feet long and 3 inches in width (5 sq ft at a cost of about $25) - as many of these radials as possible should be installed. Another approach is to use wire mesh screen (copper if possible) as a ground plane. This arrangement is the most flexible and will allow operation under all conditions (as long as your rigging stays intact). The insulated backstay is expensive ($200 or more for the two insulators) and the insulators are a weak point in the rigging design. Experts recommend replacing the insulators more frequently than any other part of your rigging. The antenna tuner (about $500) will match your backstay to all frequencies without damage to your transmitter - but the efficiency of transmission may be less than 10% (150 watts from the transmitter but only 15 watts out via the antenna with the rest of the energy showing up as heat in the tuner and ground losses). Modern antenna tuners will match a transmitter to a length of string soaked in salt water - but this does not mean you will be efficient at transmitting. The total installation may well take several man days and require access to every nook and cranny of the boat - a REAL mess!! Also, on a Flicka, the length of the backstay and the length for installing counterpoise radials is minimal at best. My Non-Expert Antenna Choice for a Sailboat My use for SSB radio is as a means of communication with friends and family - digital transmission for eMail will be the major mode of operation. This means that my needs are very limited and I will only use the system at anchor and not while underway. As a coastal sailor, a good VHF system is much better for emergency and routine marine communication. At anchor, I can raise a temporary shortwave antenna into the rigging, get my eMail, and then put the system away. The design of high quality temporary antennas of this type are well understood and can they can be produced inexpensively. Amateur radio operators have been using them for years on Field Day and other emergency preparedness tests. Most automated communications is limited to a narrow range of communication frequencies with world wide coverage potential (30 and 20 meter wavelength). For the frequencies I need access to, an efficient 1/2 wave length dipole antenna will range from 46 feet long down to 33 feet long (30 and 20 meter wave lengths) as end to end dimensions. Dipole antenna's consist of nothing more than two sections of stranded copper wire (insulated AWG 14 will do) with an insulator in the middle of the two sections and on both ends - the whole thing looking like a clothess line. The connection to the transmitter is made at the center (called the feed point) - generally with high quality coaxial cable. Physically, this antenna can be aranged in two ways - as an inverted "V" with the center raised to the top of the mast and the ends suspended by their insulators fore and aft, or as a "sloper" with one end at the mast head and the other end suspended from the pushpit. The single largest advantage of this arrangement is that NO COUNTERPOISE IS REQUIRED!! There is no free lunch, while efficient, this setup means that you should construct one antenna dedicated for each band of operation. Also, the antenna is somewhat directional with very little radiation off the ends of the antenna (fore and aft). If you sailboat is swinging significantly at anchor, a contact might be difficult to maintain unless you use two anchors. Using the Dipole antenna approach is especially attractive to a salt water sailor since the electrical properties of salt water make it an ideal reflective ground for radio frequencies. This is why long distance transmission of radio waves over salt water has long been known to be very efficient. Additionally, that lonely anchorage also is missing much of the the man made electrical interference that radio operators need to spend so much effort at overcoming. There is an alternative arrangement of the inverted V dipole antenna that is even simpler to construct for use on a small sailboat. This is the Resonant Feed-Line Dipole antenna and details on it's design are available via the internet. I'll start with this system since it is so easy to set up. Another choice for antennas is the Pro-Am Valour (Ham Stick) series of antennas. At the frequencies I operate for email, these antennas are efficient and easy to set up. The mount is attached to the pushpit and the toe rail of the boat is ties electrically to the pushpit to act as a radial counterpoise. Additionally, a section of ten feet of tinned braided copper cable is run to the saltwater whenever this antenna is in use. Once a good quality Single Sideband receiver (Unfortunately, the Elecraft K2 only covers the Ham bands and receipt of weather FAX is not possible with this radio.) and computer are on board, a logical extension is to use the equipment to receive the latest weather information. The Coast Guard has a broadcast schedule of weather products for mariners that includes a number of charts as well as text and voice transmissions of weather reports. A schedule of transmission frequencies and times is available on the web. Broadcasts that cover the area of interest for me (Florida with points south and east) are issued from Belle Chase LA. Currently (Spring 2000), they use frequencies of 4317.9, 8503.9, and 12789.9 with the schedule of transmissions starting at 00:00, 06:00, 12:00, and 18:00 UTC - each scheduled transmission block lasts just over 2 hours. A complete broadcast schedule is also issued at 06:30 and 18:30 UTC in HF-Radio FAX format. To receive the broadcast, tune 1.9 KHz below the listed frequencies using UPPER sideband. Remember that atmospheric conditions, distance from the transmitter, and time of day will determine which of the listed frequencies you will be able to receive from your current location. Don't expect these weather maps to be in extreme detail like your local TV news - they are general in nature but will give you a good idea of the conditions you are likely to encounter when you are out of range of the usual sources of broadcast weather data. Knowing when a Weather FAX chart will be transmitted won't help if you can't decode the chart to display on your laptop computer. For occasional use, I suggest JVComm 32 (In January 2000, the most current version was 1.0 and the registration fee was $68). This shareware program will use the Soundblaster compatible hardware on your Windows 95 or higher laptop computer to decode the transmission and display the received chart on the computer screen. Under some conditions, a direct connection between the computer and radio is not even necessary since the decode process can use the computer's microphone input if the computer and receiver are close together. Be sure to test the software using the demo download on your computer system before actually purchasing it. The current version software (Version 1.0) requires a download of about 3.5 MB. If you need access to weather maps more frequently, the dedicated HF radio modems are much better and more reliable. JVComm32 supports the Pactor IIe modem directly so there is no need for the sound card. The Coast Guard stations also broadcast weather information in English (using a computer generated voice that is sometimes difficult to understand) on the same frequencies. There are other weather broadcast formats available in text form (a radio modem is required) - information is on the links page. While we are on the subject of Time - do not neglect to set your watch using the WWV broadcast on a frequency of 2.5, 5.0, 10, 15, or 20 MHz. This is also a nice way to check the calibration of your receiver's frequency display. Sailboat SSB Directionality Effects The Hamstick antenna described above is normally expected to radiate it's signal uniformly in all directions. The caveat is that this radiation pattern is expected when the antenna is mounted in the clear and away from any other metal objects. Unfortunately, a sailboat is far from a clear location for an antenna mount. Computer antenna modeling shows that the 25 foot mast on a Flicka is the perfect height to act as a passive antenna element on frequencies of 14 MHz (20 meters) and above. Depending on the frequency in use, the mast will function as either a director or a reflector. This means that the majority of the radio signal will be beamed either off the bow or off the stern - again the direction will be frequency dependant. Since I use frequencies in the 30 meter band (around 10.125 MHz) most often, I do not experience this directionality effect. However, the computer models clearly show that I should avoid higher frequencies. This page was last updated on July 29, 2001 08:25 AM |
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