Antenna and cable<\/h2>\r\nA VHF radio needs a good antenna and an equally suitable antenna cable. Often a RG58U cable is used, which works well up to a cable length of 6m but brings a strong loss of transmission power at greater lengths. Therefore, it is necessary to check the cable length of the antenna cable before installation in order to choose a suitable cable.\r\n\r\n \r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n

Cable designation<\/th>\r\n	Diameter<\/th>\r\n	Max. Length with low power loss<\/th>\r\n<\/tr>\r\n<\/thead>\r\n
RG58U 50 Ohm<\/td>\r\n	5 mm<\/td>\r\n	6 m<\/td>\r\n<\/tr>\r\n
CO100 50 Ohm<\/td>\r\n	6 mm<\/td>\r\n	30 m<\/td>\r\n<\/tr>\r\n
Aircell 7 50 Ohm<\/td>\r\n	7 mm<\/td>\r\n	30 m<\/td>\r\n<\/tr>\r\n
RG213U 50 Ohm<\/td>\r\n	13 mm<\/td>\r\n	40 m<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n \r\n\r\nThe antennas are available in different lengths. The longer the antenna, the better the transmission performance when the antenna is vertical. Shorter antennas are often used on sailing yachts, because this allows the radiation to be targeted parallel to the horizon even when the antenna is tilted. Therefore, even with long antennas it is important that they are mounted vertically and not tilted backwards, if maximum range is desired.\r\n\r\n<\/a> The emission for a short antenna is circular, so heeling does not matter here. Of course, the emission occurs further than the area drawn in yellow. This is only to clarify the function so chosen!<\/small>\u00a9 Werner Ober GmbH & Co KG Stock<\/span>[\/caption]\r\n\r\n<\/a> The transmission at a long antenna is elyptical, therefore the heeling has a negative effect here. The signal goes into the water or the sky. Naturally, the transmission takes place further than in the yellow drawn area. This is only to clarify the function so chosen!<\/small>\u00a9 Werner Ober GmbH & Co KG Stock<\/span>[\/caption]\r\n\r\n \r\n\r\nAn equally important point is the correct mounting of the antenna connectors. The PL259 connector is the most common connector for radio cabling. Here it is particularly important that there is good contact with the cable shield and that the hot lead (inner lead of the coaxial cable) is soldered to the connector (see blue arrow).\r\n\r\n<\/a>\r\n\r\n \r\n\r\nIf an AIS with an antenna splitter is also mounted on the vessel, must<\/strong> use a wideband VHF antenna (20MHz) so that both the radio and the AIS can work well. With a standard VHF antenna, a standing wave error may be displayed on the AIS and the AIS transmission may not occur.\r\n Range of VHF radios<\/h2>\r\n.\r\nThe theoretical range of a VHF radio can be calculated very easily. For this purpose, the following formula applies:\r\n distance (nm)<\/strong> = \u221a(1.42 x antenna height in feet).\r\ne.g. if an antenna is on a 30 foot mast (about 9m):<\/em><\/p>\r\n\r\n \u221a(1.42 x 30) = 6.5 nautical miles (approximately)<\/strong><\/h3>\r\n Approval<\/h2>\r\nAny radio equipment (like all transmitting equipment as well as radar, AIS, SART...) must be approved in that country under whose flag the vessel is registered. In addition to the Declaration-of-Conformity, the notification (this is done by the manufacturer\/importer) is required in the corresponding country of registration. During registration, the MMSI (M<\/strong>obil M<\/strong>aritime S<\/strong>hip I<\/strong>dentity) is assigned, which must be programmed into the radio. For equipment that is also used on inland waterways, the telecommunications authority also issues the ATIS number.\r\n\r\nAs of November 2018, manufacturers are only allowed to sell marine radios with the ability to connect an external GPS antenna. Even if the radio has a built-in GPS, this connection must be available. Devices without DSC (Digital-Selective-Calling = this is the new distress call facility where the GPS position and the MMSI number of the vessel is always sent along), will no longer be allowed.\r\n\r\nAlso note that the Declaration-of-Conformity is required for registration and it must not be older than 5 years. If you buy a used boat and there is already a radio with MMSI number installed, must<\/strong> delete this number. You can not do this yourself and can only be done by a corresponding service station of the radio manufacturer. (for Raymarine e.g. company Werner Ober GmbH & Co KG - Yachtelektronik, contact see below).\r\n\r\nVHF handheld radios can be approved on Austrian-flagged vessels only in addition to a fixed installed radio system and must of course also be registered.\r\n Features and options<\/h2>\r\nEvery current VHF radio must have the DSC function described above. In case of distress at sea, the corresponding button (this is red and secured behind a flap) is pressed. Then predefined distress messages are shown on the display and the applicable one is selected, and the distress call is confirmed.\u00a0The unit will then transmit the distress message with the current position, date and time until a coastal radio station responds. It then switches to a working channel to coordinate assistance. During this time, there is no need to continuously radio mayday-mayday, but work can continue on the problem resolution.\r\n\r\nThere are also radios available with multi-station function or in a black box solution (the transceiver is installed hidden and \"only\" the handsets with display are visible).\r\n\r\nWith these devices several radio stations can be connected to one device, e.g. to be able to communicate from the flybridge as well as from the main helm station.\r\n\r\nThese second stations can be solved with cable or also wirelessly. With many devices there is also an intercom function (intercom) between the stations.\r\n\r\n \r\n\r\n<\/a> Ray90 from Raymarine with black-box design and the ability to connect wired and wireless RayMic handheld.\u00a9 Raymarine<\/a><\/span>[\/caption]\r\n\r\n \r\n\r\nWith the highest quality radios, a pressure chamber horn (Loudhailer) with intercom function can also be connected. This allows the radio to easily talk to the crew member at the forecastle or the marina worker. These radios also have the ability to use the pressure chamber horn as a foghorn or siren.\r\n\r\nCombined radios with built-in AIS receiver<\/a> are also available. Radio systems with built-in AIS transponder are hardly available and very vulnerable, because the transmitting power must be switched continuously between AIS transmission and VHF transmission. This is VERY hard on the power amplifiers and reduces the lifetime.\r\n\r\nThe formerly used function to connect to the public telephone network from a coastal radio station is hardly used anymore and has been largely replaced by cell phones. Only in areas with poor GSM network coverage is this function still occasionally used.\r\n\r\nIn conclusion, VHF marine radio will remain in use as a means of communication internationally and near the coast for a long time to come and is also mandatory in almost all equipment lists.\r\n\r\n \r\n Information and advice<\/h2>\r\nSpecialist for consulting and installation of yacht electronics is the company WERNER OBER GmbH & Co KG - Yachtelektronik.\r\n\r\n<\/a>\r\n\r\n \r\n\r\nWerner Ober GmbH & Co KG<\/strong>\r\nYacht electronics\r\nReichsstrasse 38\r\n6890 Lustenau | Austria\r\n\r\nTel: +43 (0)5577 824 19<\/a>\r\nEmail: werner.ober@yachtelektronik.at<\/a>\r\nWeb: www.yachtelektronik.at<\/a>","post_title":"Communication means on board: <\/span><\/span>UKW radio (marine radio) on yachts","post_excerpt":"","post_status":"publish","comment_status":"open","ping_status":"closed","post_password":"","post_name":"ukw-radio-sea-radio-on-board-yacht-boat","to_ping":"","pinged":"","post_modified":"2022-05-29 14:17:51","post_modified_gmt":"2022-05-29 12:17:51","post_content_filtered":"","post_parent":0,"guid":"https:\/\/www.sea-help.eu\/news-general\/ukw-radio-sea-radio-on-board-yacht-boat\/","menu_order":0,"post_type":"post","post_mime_type":"","comment_count":"0","filter":"raw"}],"next":false,"prev":false,"total_page":1},"paged":1,"column_class":"jeg_col_2o3","class":"epic_block_25"}; Page 1 of 2 1 2 Next SeaHelp Service Push Service & Newsletter SeaHelp News Latest articles News General MARINA COMPARISON 2026: Croatia’s marinas are getting more expensive in 2026 – but not everywhere. 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