HF/SSB in the boat - Installation tips

This blog post provides answers toå the most frequently asked questions and applies to all types of HF installations in boats/vessels.

Background
A marine HF station must be used when communicating with coast radio stations or other vessels. The device must be approved and meet the requirements set for; such a station. Such a station must not be used for other radio traffic, such as amateur radio. Likeå for an amateur radio station not to be used for contacts with coast radio stations or other vessels.

For carrying; use the sender on a marine HF /SSB station you must have a radiotelephony certificate. This is done after training and tests at Stockholm Radio. Such a certificate. Does not apply to amateur radio traffic.

For carrying; to use an amateur radio station, you must hold an amateur radio certificate, and hold permission to use such. This requires certain technical knowledge and moderate skill in morning telegraphy.

Connection of antenna tuner to radio station
Made with a coaxial cable (type RG-58 enough for most installations with a distance of up to 30 meters). In case thereå greater mechanical strength is desired, RG-213 can be used.

It is a good rule to make a so-called RF choke (HF spärr) on the cable at each end. Wrap the coax in a small ring 10 to 15 turns, 100-150 mm diameter. Placed behind the radio station and just outside the antenna tuner. This HF block prevents the antenna system from using the coax as a ground plane. In case of problems, it is easy to put on; a split ferrite core and improve the properties of the HF barrier.

Furthermore, a manual cable is needed. This consists of a 4x0.5mm2 or larger, up to 30 meters. For longer lengths, 1.5mm2 was used. It is very important to keep track of; the colors. Incorrect connection invariably leads to damage. Även på this cable it is very suitable to wind HF blocks in each end. There is no benefit to save on; the cable lengths. Here, ferrite cores may be needed. Note that the ground wire must be connected differently in the AT-130 depending on which radio station is being used. For amateur radio, the earth conductor is connected to E. På GMDSS the station to AntC.

The ferrites can be placed on without the cable having to be pushed through. The ferrites prevent HF from the antenna from propagating through the boat to the radio's station. På some frequencies ”want” antenna have a ground plane.

The antenna
The most common is to use a stripped brace as an antenna element. Try to get så Long and free antenna as possible. In practice, 10-18 meter stern stays usually apply. Place an isolator that can withstand the force a few meters from the top of the mast, as well as one at the lower end of the stay

(0.5-1.5 meters from the deck). The tuner is placed at the beginning of the antenna, on aft deck or just below deck. It is important to realize that the antenna starts at the antenna tuner's porcelain insulator. That point must be connected with a cable to the brace. The cable radiates and must be treated as an antenna, it wants to hang freely. It must also be taken into account that it carries high voltage when sewing.

This cable must be left free, not anchored to grounded frames. . The cable may possibly be strapped  in a few points.

It may äalso be idealé to pull it through a hose. Area 3–10 mm. As well as consider its mechanical properties. The length will be 1-3 meters. Connection to the brace is made with linen rope and can be sealed with vulcan rubber. Think about not to pull the trigger too hard; the brace may be damaged.

Ground
Grounding is the most important thing about; the entire facility. Connection to the sea is needed for the antenna to have; a good ground plane (compare the car roof and the NMT antenna). På short wave (HF) requires a larger ground than a car roof.

The antenna tuner's ground screw must be connected to the sea with a short cable. The most common is to install sintered bronze plates below the waterline near the antenna tuner. One more två meters between the tuner and these plates are practically standard distances.

Grounding to the engine block, cooler, propeller, etc. can sometimes be necessary. A good idea is to prepare the installation with ground wires extending from these points. These cables can then be connected and tested at the tuner's ground screw. For boats with tin hulls, connect to the hull near the antenna tuner.

The ground conductors should be conductors with low impedance. It means rough area, 6–20 mm2. You can also use copper tape, copper tape. You can also run several parallel wires to the earth points. Copper floats are good options.

The radio station
For this, the strömförsörsösösösösösösösösösö A card weighing station needs 12 volts and roughly 20 amperes when transmitting. Nominal voltage is 13.8 volts +- 15%. ( 11.7–16 volts).

A lead-acid battery without charging will soon drop to 12 volts and there is no room for voltage drop in the supply. Use the included cables directly connected to the battery. If they are to be removed, the area must be substantially greener. It is important that both the plus and minus cables are connected directly to the the battery. Do not use the hull as a negative conductor. No additional grounding of the radio station is required. In order to prevent creepage currents with corrosion as follows, it is important that the electrical system is floating, i.e. that neither plus nor minus from the battery is connected to the engine block. Monitor ändå the first time the boat's underwater details for corrosion damage.

Problem
A leisure boat has a small place for a short wall installation. Bad ground, short antenna etc. means that one never hurts; well-designed installation äandå är a compromise. Problems can occur, often on certain frequencies. You can be surprised that på at a certain frequency it becomes all kinds of ghosts. Typical problems can be that the transmission interferes with other electronics in the boat, the transmitter interferes with itself, you hear that it smells bad, you worry about the radio station or the microphone. Most errors are due to that the antenna system ”wants” better earth.

This can be prevented by alternative earthings, ferrite cores or simply by lowering the transmitter power. Think about that (-10dB) 10 watts instead of 100 watts is not really that bad; big difference and not affected by så very på the range that you think. In addition, you save electricity.

Alternative antennas
If you have a mast failure, you are without an antenna. the one that is most needed. A reservant can be a telescope measuring pö, 7–12 meters. På to this you tape a cable (1.5mm2), mount the boom diagonally upwards and connect to the antenna tuner. In port, you can extend the stay antenna by attaching a long (20 meter) antenna cable (provided with a starter rope), and throwing up the other end of the wire in a tree.

Work the earth
The earth can is solved by placing cables in the sea connected to the HF earth point (antenna tuner earth point). På the same way that some use ground wires connected to the station in case of risk of shock. It is possible to have up to 20 meters long ground wires lying around.

HF radio på sjön
HF radio på the sea can be used for a lot, security - to be able to shout at coastal radio stations, shout atå other ships in distress. In case of traffic on the emergency frequency 2182kHz you have a range of; 100-300km. Our growth is something you have to learn, but nothing is really stable. You have to take into account the time of around the clock, was på the globe you are in etc.

To listen toå the amateur bands mean that you can learn a lot about the weather's spread. You can make the judgment that the one you hear, you can also; make yourself heard at. You can listen to broadcast radio, most countries have short-wave broadcasts that are heard all over the world so äeven Sweden's Radio. Talk to Radio Sweden for the frequency table. You can receive weather faxes, which requires a modem and a computer.

All HF transceivers are able to receive weather faxes. Being in contact with your friends and other ocean sailors is very nice from international waters. As a radio amateur, being able to practice the hobby in a boat is very stimulating.