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TIP(?): Build your own HDTV UHF antenna ... CHEAP
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<blockquote data-quote="rtv" data-source="post: 400028" data-attributes="member: 12309"><p>Please note: for decent results an antenna has to be calculated exactly for your purposes - however that's not too difficult:</p><p></p><p>Length of antenna: Lambda = c / f (with c being lightspeed multiplied with the velocity factor of the material and f being the frequency)</p><p>Length of ground mashwork (e.g. those cloak hooks) should be: Lambda / 4</p><p></p><p>Example: 299.792.458 x 0,951 (copper)[m/s] </p><p> /</p><p> 478.000.000 [Hz] (assuming our lowest channel is on UHF 482 MHZ - subtract half the bandwith of each channel which is 8MHZ). </p><p> = </p><p> 0,5964 [m]</p><p></p><p>Antenna elements: 0,5964 / 4 = 0,1491 [m]</p><p></p><p>At these frequencies it doesn't come down to the last millimeter but you should do the basic calculation for your frequency first <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink ;)" loading="lazy" data-shortname=";)" /></p></blockquote><p></p>
[QUOTE="rtv, post: 400028, member: 12309"] Please note: for decent results an antenna has to be calculated exactly for your purposes - however that's not too difficult: Length of antenna: Lambda = c / f (with c being lightspeed multiplied with the velocity factor of the material and f being the frequency) Length of ground mashwork (e.g. those cloak hooks) should be: Lambda / 4 Example: 299.792.458 x 0,951 (copper)[m/s] / 478.000.000 [Hz] (assuming our lowest channel is on UHF 482 MHZ - subtract half the bandwith of each channel which is 8MHZ). = 0,5964 [m] Antenna elements: 0,5964 / 4 = 0,1491 [m] At these frequencies it doesn't come down to the last millimeter but you should do the basic calculation for your frequency first ;) [/QUOTE]
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