What is SSB Radio?

Everything you need to know about SSB marine radio

For many who sail around the world, a short-wave radio system is a must-have on board, as an SSB marine radio system can be used for very long distances. It is easy to see why sailors would want to communicate with each other, particularly on nautically demanding sea passages. In addition to radiotelephony, e-mails can be sent and weather information received via a Pactor modem. All components must be carefully installed in order to operate the system without any problems. Find out which components you need and what to be aware of during installation in our SSB-Marine Radio Guide.

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What is SSB radio?

SSB stands for Single Sideband. An SSB radio modulates a special type of wave during transmission, also known as short-wave radio. Short-wave radio equipment on ships is part of the Global Maritime Distress and Safety System (GMDSS) established under SOLAS, the International Convention for the Safety of Life at Sea.

Marine radio via Very High Frequency (VHF) or Short Wave (SW) - What is the difference?

Marine radio includes both (VHF) and Short Wave (SW) frequencies. The difference between the two lies in the type of frequency range used. The VHF range is limited to about 25 nautical miles. Short-wave radio, on the other hand, also covers longer distances due to the reflection from the Earth’s outer air-layer (the ionosphere). The term HF radio (High Frequency radios and/or High frequency marine radios) is also used. VHF and HF radios can be operated with the same MMSI number. Application for a separate MMSI number is not required when purchasing an SSB radio system.

SSB mood

Everything you need to know about SSB marine radio

The short-wave range is used in both maritime and aeronautical radio for long distance as well as in military and amateur radio, and is crisis-proof. An SSB radio device is useful in maritime radio communication, above all for long-distance sailing, as it allows radio signals to be transmitted and received from almost anywhere in the world. Even in tricky passages, SSB radio and the worldwide radio network allow other sailors to communicate with each other and share breakdown and repair advice or even medical help. Sailors can communicate via SSB radio on the shortwave frequency *pre ARC Radio Net 8.297*. A Facebook group of the same name also allows users to listen without a radio on land.

Shortwave is also often used for radio communication on regattas. At the World ARC, Oyster World Rally or the Sydney Hobart Race, for example, shortwave equipment is obligatory. Further regattas/rallies all over the world are organised by the World Cruising Club.

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Should I buy an amateur radio device or an SSB marine radio?

Which device you choose depends first of all on the radio certificate you have, either an amateur radio certificate (HAM) or a marine radio certificate (LRC). SSB amateur radio systems are usually cheaper to purchase than SSB marine radios, but the amateur radio certificate is much trickier and more complex to obtain than a marine radio licence, also known as a Long Range Certificate (LRC). Amateur radio training also teaches basic electrotechnical know-how.

The more expensive SSB marine radios, on the other hand, often have a DSC function. DSC stands for Digital Selective Calling. DSC is a marine radio call method that uses acoustic and optical signals to identify incoming calls. This means that there is no need to constantly monitor radio traffic for relevant calls.

The data transmitted via DSC appears on the DSC controller of the radio system called and is also stored in a memory so that it can be recalled at any time. A separate antenna is required for the DSC function. For SSB marine radios, we recommend our AA-35 active/DSC antenna to use the DSC function.

Both SSB amateur radio equipment and SSB marine radio receivers operate on frequencies between 3 and 30 MHz Amateur radio users are relatively free to choose a frequency in the ranges 1.8 / 3.5 / 7 / 10 / 14 / 18 / 21 / 24 / 28 MHz in accordance with frequency usage plans. Marine radio users have fixed channels in the frequency range 2 / 4 / 6 / 8 / 12 / 16 / 18 / 22 / 25 MHz You can listen on all frequencies, no matter which radio certificate you have.

SSB-Amateur Radio Equipment vs. SSB-Marine Radios

SSB-Amateur Radio Equipment SSB-Marine Radios
Certificate Amateur radio certificate (HAM) SMarine radio certificate / Long Range Certificate (LRC)
Transmit frequencies 1,8 / 3,5 / 5 / 7 / 10 / 14 / 18 / 21 / 24 / 28 MHz 2 / 4 / 6 / 8 / 12 / 16 / 18 / 22 / 25 MHz
Receive frequencies 0.5-30 MHZ pervasive 0.5-30 MHz pervasive
Frequency selection Free frequency selection in accordance with frequency usage plans Preprogrammed channels
Costs Cheaper to purchase More expensive to purchase due to additional functions such as separate 2nd receiver, remote control unit, splash-proof display. Display of the current position with connected GPS device. 150 Watt transmitting power.
DSC No Yes

What should I know when installing SSB radios?

The best SSB radio is of little use if the system is not installed correctly. Proper installation must include several points:

1. Grounding the short wave antenna

A short-wave antenna should typically be symmetrical in shape with two conductors. Since most ships are single-mast, the second conductor of an asymmetric antenna can be balanced by tuners and seawater grounding. Depending on the material of the hull there are different possibilities:

Grounding on ships with metal hulls

On ships with metal hulls, care must be taken that no DC voltage is applied to the hull via the tuner. Even if antifouling paint has been painted, there is still contact to the seawater by means of capacitive coupling. Use an electrolysis blocker or DC blocker, such as the DCF-47, to prevent voltage from reaching the hull.

What should I know when installing SSB radios?
Grounding on ships with GRP and wooden hulls

Grounding on ships with GRP and wooden hulls

There are several possibilities for GRP and wooden hulls. Ground plates made of bronze material, also known as Dynaplates, ensure the correct earthing and that interference is prevented. The grounding plates should only be used for grounding the tuner and not for other electrical installations. For the grounding plates it is important to choose a size sufficient for SSB radio. Our rectangular grounding plates measuring 300 x 80 x 13 mm are ideal for this purpose. If you have a wooden hull, simply install the supplied fibreglass plate between the grounding plate and the hull. Grounding plates should never be painted over! After 6 months, algae and mussels can form on the rough surface of the bronze material, which limits the function of the grounding plates. In this case they must be cleaned, preferably with a metal brush, or completely replaced. You should always attach the grounding plates using the floating method, so you can uninstall and clean the pads at any time without taking the boat out of the water.

SSB Radio Expert Tip

SVB recommends grounding GRP and wooden hulls by using SSB-Ground-Paint. This is a highly concentrated, silver-plated solvent-free copper coating which is applied as close as possible to the tuner, below the waterline in the bilge or in the aft area for good grounding on approx. 3 m². Here, the painted surface represents one half of the condenser and the seawater the second half. Both halves are separated by the hull. The advantage of this method is that the painted surface is maintenance-free. It can be painted over with boat paint as desired and the tuner can be connected to the painted surface with a wide copper band. SSB-Ground-Paint does not serve as lightning protection grounding.

SSB Grundfarbe

KISS-SSB Grounding System

A third option is the KISS-SSB grounding system. It consists of a 300 cm long hose with a 119 cm long supply line. Inside, wires for the respective resonance frequencies are located. The KISS-SSB is connected to the tuner's grounding screw and placed loosely in the fuselage. It is important not to install the grounding system too close to the live cable. The KISS-SS grounding system does not serve as ground protection against lightning.

2. Choosing a suitable antenna tuner

All SSB radio systems have an antenna tuner. In shortwave, a wide range of 2-30Mhz is used. This range should be covered by an antenna (isolated backstay or whip antenna). These antennas have a resonance frequency depending on their length. In order to be able to use the antenna beyond this resonance frequency, an automatic antenna tuner is used, which electrically "extends" or "shortens" the antenna and brings it back into resonance. The tuner should be installed inside, as close as possible to the antenna. Reliable antenna lengths for the backstay are 7.0 m to 13.5 m and max. 17m. The antenna starts at the tuner output and the cable to the backstay is factored in.

3. Make sure good quality of cable connections for best transmission and reception quality

Every loose connection and every area that is too small for the transmission of shortwave power has a negative effect on the transmission and reception quality of the SSB radio system. There may be a risk of short circuits and corrosion. The coaxial cable connecting the radio and tuner should be of low attenuation. The soldering of PL plugs must not allow any contact between the conductor and the shielding and there must be sufficient contact area for the conductor. As an antenna for short-wave radio systems, a section of the backstay is usually electrically insulated. As an alternative to an insulated backstay, the Glomex rod antenna can also be used. If the insulated backstay is used as an antenna, it is important to establish a good connection with the high-voltage cable via a backstay clamp. A good connection is achieved by a large contact surface of the clamp to the insulated backstay and a waterproof connection of the high voltage cable to the tuner and antenna.

4. Choose installation location with care & maintain necessary distances

When installing SSB radios with a shortwave frequency, it is essential that the necessary distances are maintained to avoid interference or loss of performance. It should also be noted that the feedline from the antenna tuner to the insulated backstay radiates a signal. A UV-resistant GTO-15 high-voltage cable should be installed between the tuner and antenna. A coaxial cable, which is installed by some shipyards here, keeps the tuner from adjusting the antenna system correctly and a large part of the output is not radiated by the shielded coaxial cable. The GTO-15 should be kept at a distance from the uninsulated part of the backstay using a so-called "standoff". With contact or too close installation of the high voltage cable to the uninsulated part of the backstay will result in a loss of output.

For metal hull sailing yachts, large deck insulators should be used when routing cables through metal, otherwise they will act as a capacitor and the output will remain below deck.

As a general rule, any type of antenna on board should be as far away from metallic objects as possible for best results. When installing the tuner, proximity to the ground is extremely important.

SVB provides a detailed installation manual with every SSB radio system purchased.

Installation example of an SSB radio:

Installation example of an SSB radio
  1. Backstay clamp
  2. GTO-15 High-voltage cable
  3. Isolator
  4. Standoff
  5. GPS Antenna NMEA0183
  6. DCS Antenna AA-35
  7. ICOM Automatic Tuner AT-140
  8. SSB Ground Paint 3m2 (connected to tuner with copper foil)
  9. IC-M802 main unit
  10. IC-M802 Display
  11. SP-24 speaker
  12. Laptop
  13. DR-7400 HF modem
  14. Battery / power supply

How can I receive email on board? Short wave data transfer

During longer journeys it may be useful to receive data on board, e.g. e-mails, weather faxes or weather GRIB data. This can be done via a Pactor modem. The modem is connected to the transceiver and a PC or laptop via USB or Bluetooth. The Pactor modem then converts the computer data so that it can be transmitted via short wave. The data is exchanged between the ship and shore stations, with the shore stations transmitting the short-wave data to the Internet.

First, the owner of the Pactor modem sends a GRIB file containing the sea area and the required data (wave height, wind direction, air pressure, etc.) to the land station.


The land station transmits the short-wave data to the Internet. After a few minutes the ship receives a GRIB file with a detailed weather forecast for the area and the required data.


In addition to the weather forecast for a specific region as a GRIB file, the Pactor modem can also be used to send a weather fax of the general weather situation.

ssb weather fax

Pactor modems are manufactured by the German company SCS. In our range you will find the DR-7400 model, which already uses the new Pactor 4 method, also called P4 dragon, which improves speed. The DR-7400 Pactor modem is surpassed only by the DR-7800, which also has a built-in display and is therefore much more expensive. We do not have this model in our standard range, but we will be happy to order it for you if you are interested. A third Pactor modem that is available on the market is the PTCIIIusb.

This modem has a much lower speed than the DR-7400 and is no longer available from us. To mount your Pactor modem on board, you will find a mounting kit with so-called Pactor brackets, brackets for mounting the modem on your yacht.

A Pactor modem has even more advantages: With a Pactor modem and an SSB system, Navtex weather messages can be received. A separate Navtex weather receiver is not required. The same applies to weather faxes. Even small e-mail attachments such as pictures up to 50 KB can be sent with a Pactor modem.

Possible providers for transferring data from your Pactor modem

To use the Pactor modem, you need a provider who can supply you with the worldwide network of radio stations, making data transfer possible in the first place. Depending on which radio license you have, two providers are possible:

1. Winlink / RMS Express

Winlink is a network that is operated free of charge by and for amateur radio operators. There is no need to register to participate in the service, just enter your callsign and password in the appropriate software. For each callsign the maximum usage time is limited to 30 minutes per day in order to offer each sailor a free frequency.

2. Sailmail

Sailmail is a network that is operated on HF Marine Bands and need a payment of $275 for one year. There is need to register at the sailmail website in the service, just enter your callsign and adress . For each callsign the maximum usage time is limited to 90minutes a week.

Provider via Winlink - 30 minutes a day no costs via Sailmail - 90 minutes per week cost US$ 275 per year
Stations Almost worldwide (shortfalls in the Pacific) Worldwide
Reliability good very good

SSB testing facility at SVB in Bremen

To test radio systems, SVB has set up a remote radio system in Bremen. The system covers a frequency range of 0.5-30MHz.

SSB testing facility at SVB in Bremen

Which frequencies and programmes are recommended for shortwave radio in Europe and the Caribbean?

Via the shortwave frequency pre ARC Radio Net 8297 khz in J3E/USB sailors can communicate via SSB radio on a daily basis. A Facebook group of the same name also allows communication on land.

Weather GRIB-Files & Software by WetterWelt

Weather GRIB files are available for sailors with SSB radio and Pactor modem or an Iridium telephone. With a special WetterWelt software you can extend the range of weather data.

Chris Parker’s Weather Net

Chris Parker is very well known in the USA. He also makes weather reports and weather advice via shortwave and talks directly to the sailors via shortwave. He transmits all year round at 2200 UTC on the SSB frequency 8137 kHz and transmits simultaneously on 12350 kHz, each in J3E/USB.

Trans-Atlantic Radio Net

The Trans-Atlantic Radio Net broadcasts daily in winter and spring at 2130 UTC, half an hour before Chris Parker's Weather Net on the SSB frequency 12350 kHz.

German Weather Service (DWD)

The German Weather Service (DWD) also has a shortwave frequency that can be used to transmit weather reports in spoken form and receive them with an SSB system. The spoken transmission of the sea weather report is transmitted on 5905 kHz and 6180 kHz in AM at the following transmission times:

SSCA Net Callsign KPK

Many German sailors are also registered with the American organisation SSCA, which operates its own coastal radio station with the call sign KPK. SSCA is the equivalent to Trans-Ocean in Germany. Many sailing boats also have SSB equipment on board. It is transmitted daily at 1215 UTC (0715 EST or 0815 EDT) on the frequency 8104 khz in J3E/USB.

Med Net

Sailors in the Mediterranean region hold daily exchanges at Med Net in spring, summer and autumn from Monday to Saturday. The check-in frequency is 6516 kHz. The frequency is then changed to 8131 kHz and finally to 12359 kHz in J3E/USB.

Where & When Propagation Tool

The Where & When Propagation Tool is also available to clearly receive or send calls from or to the other end of the world via SSB radio. The program shows at which time and on which frequency, depending on your current position and the approximate position of the other party, a call works particularly well.

North Sea, Baltic Sea and German coastal areas:

  • 06:00-06:30 UTC
  • 12:00-12:30 UTC
  • 20:00-20:15 UTC

Mediterranean Sea:

  • 16:00-16:30 UTC
  • 20:15-20:30 UTC
Written by our SVB (technical) experts

Written by our SVB (technical) experts

Our team of SVB technical experts is there to give our customers professional advice on all matters relating to technology on board. With specialist know-how, extensive training, and a technical flair for electrical connections, fittings etc, our crew are more than qualified to advise our customers.