HAM and SSB radios use the same basic frequency ranges from two MHz up to 22 MHz, with HAMs allotted frequencies extending on up to nearly 30 MHz. The actual frequencies, however, are different, and by FCC regulation, many radios are limited to only the legal bands for which they were designated. While some cruisers know how to "open up" their radios transmitting capabilities so that a HAM radio becomes able to transmit on Marine SSB frequencies, this practice can result in stiff fines, confiscation of the radio equipment, and permanent loss of the radio license. The FCC has recently "type certified" radios capable of transmitting on both HAM and SSB frequencies, and if getting a HAM license in the future is a possibility, buying a combination HAM/SSB radio is a wise move. You will not be legally able to use the HAM portion until you obtain the proper license (except in an emergency), but it will save purchasing another radio in the future.
Both HAM and SSB transmissions are carried by one half of an Amplitude Modulation (AM) wave. We are all familiar with many of the properties of double sideband AM radio broadcasters, where stations a continent away can be heard at night but only travel a few miles during the day. Single sideband transmission is defined, simply, as the suppression of one half of the carrier frequency, and so each transmission is completed either on the "lower sideband (LSB)" or "upper sideband (USB)." All Marine Single Sideband transmissions, including weather fax and voice transmission are conducted on the USBHAM transmissions below 10MHz are on the LSB while those above 10MHz are on the USB. As you can see, the term Marine Single Sideband is somewhat of an unfortunate misnomer since HAM operators are also transmitting in a single sideband format.
It is critical that every boat going out of the range of VHF or other coastal sources of information on weather or other hazards have at least a modest HF receiver. A simple HF receiver allows every cruiser to listen to the active cruising world but without the ability to transmit. When considering the purchase of a HF receiver, it is important that you understand the difference between the inexpensive types that receive only AM (double sideband) broadcasts and a model capable of single sideband reception. Look for a model that has a sideband switch or BFO (Beat Frequency Oscillator) that allows you to switch from USB to LSB. Radios that receive full AM (double sideband) will only garble both HAM and SSB transmissions, making them unintelligible.
MARINE SINGLE SIDEBAND (SSB) The equipment required for a SSB radio station is the radio, which depending on features will cost in the $1,500 to $3,000 range, a tuner, an antenna, and a ground plane. SSB radios come with or without automatic internal tuners but, whether internal or on optional separate unit, the automatic variety makes the radio easier to operate, especially for novices. If you have a good background in electrical installations and a complete toolbox, you can probably install a SSB system yourself, but professional installation is recommended for the most effective operation. Most sailors run the antenna the length of the backstay with insulators at either end, keeping the lower one just above the crews reacha live transmitting wire antenna has been known to cause burns. A good antenna, ground plane, radio, and tuner will provide worldwide communications on a wide frequency range.
HAM RADIO Amateur radio operators are generally called HAMs, and they have been instrumental in experimenting with and advancing radio technology for over a century. Again, the term "amateur radio operator" is somewhat misleading as SSB operators are also amateurs in the sense that their transmissions are meant to be received only by another amateur radio operator and are not for public broadcast. The main differences between HAM and SSB operators are in the licensing requirements, the number of frequencies they have available, and the type of transmissions allowed.
Many sailors consider the HAM licensing requirements a disadvantage, but the HAMs regard them as an opportunity to learn and understand more about the operation of the radio. There used to be five levels of HAM licensesNovice, Technician, General, Advanced, and Extraeach opening more frequencies for those who attained the level of competency. Each level used to have both written and Morse code exams at increasing levels of difficultyfive words per minute for Novice and Tech, 13 wpm for General and Advanced, a professional-level 21 wpm for Extra. But these levels have been reduced to only threeTechnician, General, and Extra. And the Morse code requirements have been reduced to no requirement at the Technician level and only five wpm for the General Class and Extra. This has made obtaining a HAM license much easier for most people. The code requirement has also been totally eliminated for folks with hearing impairments, opening more opportunities for them to enjoy HAM radio.
As with the SSB setup, a HAM rig consists of the radio, a tuner with SWR meter (if the tuner is not built into the radio), antenna with insulators, and a ground plane. Once again, unless youre handy with electronics, antennas, and ground issues, a professional installer is recommended.
Each system has its own unique qualities and the obvious choice would be to have one radio with both HAM and SSB capabilities along with the proper licenses if study time and the budget permit.
But remember, without the HAM license you cannot transmit on the HAM frequencies. The owners manual for your radio will tell you which frequencies to use for HAM or SSB transmissions. There are also guides available from the FCC, the US Coast Guard, and the American Radio Relay League (AARL).
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