{"id":5686,"date":"2012-10-21T09:00:42","date_gmt":"2012-10-21T13:00:42","guid":{"rendered":"http:\/\/www.engineeringradio.us\/blog\/?p=5686"},"modified":"2023-04-09T12:19:02","modified_gmt":"2023-04-09T16:19:02","slug":"saq-grimeton","status":"publish","type":"post","link":"https:\/\/www.engineeringradio.us\/blog\/2012\/10\/saq-grimeton\/","title":{"rendered":"SAQ Grimeton"},"content":{"rendered":"\n<p>Historic VLF (Very Low Frequency) station <a rel=\"noopener\" href=\"http:\/\/en.wikipedia.org\/wiki\/Grimeton_VLF_transmitter\" target=\"_blank\">SAQ Grimeton<\/a> will be on the air to celebrate United Nations Day on October 24th at 10:30 UTC (6:30 am EST) on 17.2 KHz CW.\u00a0 This station was established in 1922 and is the last radio station in the world employing an<a href=\"http:\/\/en.wikipedia.org\/wiki\/Ernst_Alexanderson\"> Alexanderson<\/a> <a rel=\"noopener\" href=\"http:\/\/en.wikipedia.org\/wiki\/Alexanderson_alternator\" target=\"_blank\">transmitter<\/a>.\u00a0 More information at their <a rel=\"noopener\" href=\"http:\/\/www.alexander.n.se\/startsida_e.htm\" target=\"_blank\">website<\/a>.<\/p>\n\n\n\n<p>This is a great 2011 video of a tour of the station, including transmitter start-up:<\/p>\n\n\n\n<p><iframe loading=\"lazy\" src=\"http:\/\/www.youtube.com\/embed\/-S6gXmElHoI\" width=\"640\" height=\"480\" frameborder=\"0\"><\/iframe><\/p>\n\n\n\n<p>It is great to see that old gear come to life and transmit a message.&nbsp; The electric motor\/generator sounds like a jet engine spooling up.<\/p>\n\n\n\n<p>Before solid-state or even hollow-state rectifiers, motor generators were used to create the DC voltages needed to transmit high-power radio signals.\u00a0 This method was used by high-powered Naval shore stations through WWII and beyond.<\/p>\n\n\n\n<p>By way of comparison, an average CW operator can send and receive Morse code at about 20-25 words per minute.&nbsp; A good CW operator, about 30 words per minute and a Russian CW operator, somewhere near 50 words per minute.&nbsp; This was the main wireless data transmission method until Radio Teletype came into widespread use in the 1950s.&nbsp;&nbsp; Here is a comparison of data speeds through the years:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td>Method<\/td><td>Speed<\/td><td>Bits\/S<\/td><\/tr><tr><td>CW<\/td><td>20 WPM<\/td><td>8.3<\/td><\/tr><tr><td>CW<\/td><td>35 WPM<\/td><td>14.58<\/td><\/tr><tr><td>Radio Teletype*<\/td><td>75 Baud\/100 WPM<\/td><td>41.6<\/td><\/tr><tr><td>Radio Teletype*<\/td><td>100 Baud\/133 WPM<\/td><td>55.41<\/td><\/tr><tr><td>Async data<\/td><td>300 Baud<\/td><td>300<\/td><\/tr><tr><td>Async data<\/td><td>1200 Baud<\/td><td>1200<\/td><\/tr><tr><td>Async data<\/td><td>9600 Baud<\/td><td>9600<\/td><\/tr><tr><td>Switched 56 (Switchway)<\/td><td>56KB<\/td><td>56,000<\/td><\/tr><tr><td>DS0 (POTS)<\/td><td>64KB<\/td><td>64,000<\/td><\/tr><tr><td>ISDN<\/td><td>64KB X2<\/td><td>128,000<\/td><\/tr><tr><td>DS1 (T-1)<\/td><td>1.54 MB<\/td><td>1,540,000<\/td><\/tr><tr><td>DS3 (T-3)<\/td><td>45 MB<\/td><td>45,000,000<\/td><\/tr><tr><td>Ethernet<\/td><td>10BaseT<\/td><td>10,000,000<\/td><\/tr><tr><td>Ethernet<\/td><td>100BaseT<\/td><td>100,000,000<\/td><\/tr><tr><td>Ethernet<\/td><td>Gigabit<\/td><td>1,000,000,000<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>The Morse Code (CW) and Radio Teletype data rates are not a direct comparison, as most radio teletype systems use 5-bit Baudot code instead of 8-bit ASCII.\u00a0 Morse code varied in length from one to five bits, if one thinks of each dot or dash as a data bit.\u00a0 Back in the day, before the &#8220;Netcentric&#8221; mindset, we used mainly radio teletype to communicate from ship to shore.\u00a0 A premium was placed on brief, concise, operational communications.\u00a0 Everything else was sent via the mail.<\/p>\n\n\n\n<p>It is quite amazing to see the increase in data speed, which directly correlates to information exchanged (or the ability to exchange information) in the last 90 years.<\/p>\n\n\n\n<p>To receive SAQ Grimeton, one needs a VLF receiver or converter capable of receiving 17.2 KHz and a very quiet receiver location.\u00a0 There are many VLF hobbyists that will be tuning in.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Historic VLF (Very Low Frequency) station SAQ Grimeton will be on the air to celebrate United Nations Day on October 24th at 10:30 UTC (6:30 am EST) on 17.2 KHz CW.\u00a0 This station was established in 1922 and is the last radio station in the world employing an Alexanderson transmitter.\u00a0 More information at their website. &hellip; <a href=\"https:\/\/www.engineeringradio.us\/blog\/2012\/10\/saq-grimeton\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">SAQ Grimeton<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[257,302,258],"class_list":["post-5686","post","type-post","status-publish","format-standard","hentry","category-history","tag-cw","tag-history","tag-vlf"],"_links":{"self":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/5686","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/comments?post=5686"}],"version-history":[{"count":10,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/5686\/revisions"}],"predecessor-version":[{"id":11494,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/posts\/5686\/revisions\/11494"}],"wp:attachment":[{"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/media?parent=5686"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/categories?post=5686"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.engineeringradio.us\/blog\/wp-json\/wp\/v2\/tags?post=5686"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}