{"id":276,"date":"2015-08-27T14:13:00","date_gmt":"2015-08-27T14:13:00","guid":{"rendered":"http:\/\/machineryequipmentonline.com\/video-equipment\/uncategorized\/reference-datadecibel-conversion\/"},"modified":"2015-08-27T14:13:00","modified_gmt":"2015-08-27T14:13:00","slug":"reference-datadecibel-conversion","status":"publish","type":"post","link":"http:\/\/machineryequipmentonline.com\/video-equipment\/reference-datadecibel-conversion\/","title":{"rendered":"REFERENCE DATA:DECIBEL CONVERSION."},"content":{"rendered":"<div class=\"cjman6a0dc76ead9f9\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '61e5902552e2353963d8d2f1bd1f4a8f',\n\t\t'format' : 'iframe',\n\t\t'height' : 250,\n\t\t'width' : 300,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/61e5902552e2353963d8d2f1bd1f4a8f\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.cjman6a0dc76ead9f9 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.cjman6a0dc76ead9f9 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.cjman6a0dc76ead9f9 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.cjman6a0dc76ead9f9 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.cjman6a0dc76ead9f9 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<p align=\"justify\"><strong>DECIBEL CONVERSION<\/strong>  <\/p>\n<p align=\"justify\">Field signal strengths for r.f. transmissions are often given in micro- volts per metre (\u03bcV\/m) of free space. The boundary of the service area of a UHF transmitter is taken to be the 60 dB\u03bcV\/m contour, corresponding to 1 mV\/metre. Table 24.4 converts dB\u03bcV\/m to voltage. Because the voltage given is an open-circuit one at an untuned  <\/p>\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-znwd-0ufZ_U\/Vd8a25loqCI\/AAAAAAAB2w8\/phMD276-W_M\/s1600-h\/REFERENCE-DATA-02822.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-right-width: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top-width: 0px; border-bottom-width: 0px; border-left-width: 0px; padding-top: 0px\" title=\"REFERENCE DATA-0282\" border=\"0\" alt=\"REFERENCE DATA-0282\" src=\"http:\/\/lh3.googleusercontent.com\/-lfVcbh7Bh5M\/Vd8bBK-WxeI\/AAAAAAAB2x0\/oAkzHK3n1X4\/REFERENCE-DATA-0282_thumb.jpg?imgmax=800\" width=\"244\" height=\"190\" \/><\/a>  <\/p>\n<p align=\"justify\">1 metre rod, several factors must be taken into account in calculat- ing a \ufb01gure for signal strength at the aerial socket, as follows. Field strength is related to signal strength by the factor \u03bb\/\u03c0 where \u03bb is the wavelength. Average \ufb01gures are 0.2 (\u201314 dB) in band IV; 0.15 (\u201316 dB) at the lower end of Band V; and 0.12 (\u201318 dB) at the top of Band V. Next must be added the gain of the aerial, typically 6 dB for an 18-element Yagi type, 10 dB for an 8-element Yagi and 13 dB for an 18-element Yagi. Account must also be taken of the loss in the downlead \u2013 10 metres of \u2018low-loss\u2019 coaxial cable introduces a loss of about 3 dB. Finally, allowance must be made for the fact that a practical feeder is terminated in 75 \u03a9, rather than open-circuit, and so a further loss of 6 dB is incurred. Table 24.5 gives two examples of widely different situations, in each case calculating the signal strength at the receiver aerial socket.  <\/p>\n<p align=\"justify\">Table 24.6 gives an accurate dB conversion chart applicable to r.f. levels as well as video and audio baseband signals. Standard levels for signal interchange between equipment are composite video 1 V p-p in 75 \u03a9; CVBS 1.235 V p-p in 75 \u03a9; audio 0 db = 0.775 V in 600 \u03a9.  <\/p><div class=\"zwbot6a0dc76eadb0c\" ><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-0778475562755157\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- 300x600 television-and-video -->\n<ins class=\"adsbygoogle\"\n     style=\"display:inline-block;width:300px;height:600px\"\n     data-ad-client=\"ca-pub-0778475562755157\"\n     data-ad-slot=\"6549443290\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.zwbot6a0dc76eadb0c {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.zwbot6a0dc76eadb0c {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.zwbot6a0dc76eadb0c {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.zwbot6a0dc76eadb0c {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.zwbot6a0dc76eadb0c {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<div class=\"dfcvu6a0dc76eada8e\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '0c1eb4c533eaedb7b996f49a5a4983a9',\n\t\t'format' : 'iframe',\n\t\t'height' : 300,\n\t\t'width' : 160,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/0c1eb4c533eaedb7b996f49a5a4983a9\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.dfcvu6a0dc76eada8e {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.dfcvu6a0dc76eada8e {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.dfcvu6a0dc76eada8e {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.dfcvu6a0dc76eada8e {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.dfcvu6a0dc76eada8e {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n\n<p align=\"justify\"><strong>CONNECTOR PINNING<\/strong>  <\/p>\n<p align=\"justify\">All contemporary videorecorders and many TV sets have baseband video and audio input and output sockets. The standard pin con\ufb01guration for several types of plug\/socket are given in Fig. 24.2 (on page 480).  <\/p>\n<p align=\"justify\"><strong>ABBREVIATIONS<\/strong>  <\/p>\n<p align=\"justify\">Table 24.7 lists abbreviations used in service data and speci\ufb01cations (page 490).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>DECIBEL CONVERSION Field signal strengths for r.f. transmissions are often given in micro- volts per metre (\u03bcV\/m) of free space. The boundary of the service area of a UHF transmitter is taken to be the 60 dB\u03bcV\/m contour, corresponding to 1 mV\/metre. Table 24.4 converts dB\u03bcV\/m to voltage. Because the voltage given is an open-circuit [&hellip;]<br \/><a href=\"http:\/\/machineryequipmentonline.com\/video-equipment\/reference-datadecibel-conversion\/\" class=\"more-link\" >Continue reading&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"aioseo_notices":[],"views":591,"_links":{"self":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/276"}],"collection":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/comments?post=276"}],"version-history":[{"count":0,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/276\/revisions"}],"wp:attachment":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/media?parent=276"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/categories?post=276"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/tags?post=276"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}