{"id":220,"date":"2025-10-07T10:32:47","date_gmt":"2025-10-07T07:32:47","guid":{"rendered":"https:\/\/ta9ea.com\/?p=220"},"modified":"2025-10-07T10:32:47","modified_gmt":"2025-10-07T07:32:47","slug":"icom-ic-7000-tv-frekansi","status":"publish","type":"post","link":"https:\/\/ta9ea.com\/?p=220","title":{"rendered":"\u0130com ic-7000 tv frekans\u0131"},"content":{"rendered":"

IC-7000, TV ekran\u0131 al\u0131m \u00f6zelli\u011fine sahip ve bu da g\u00fczel bir \u015fey. Ne yaz\u0131k ki ICOM, TV’yi yaln\u0131zca 40MHz ile 225MHz (185MHz aral\u0131\u011f\u0131) aras\u0131ndaki VHF bantlar\u0131n\u0131 alacak \u015fekilde tasarlad\u0131.<\/span><\/span><\/p>\n

A\u015fa\u011f\u0131da sunulan TV d\u00f6n\u00fc\u015ft\u00fcr\u00fcc\u00fc, kullan\u0131c\u0131n\u0131n 472MHz ile 657MHz (Ch22 – Ch44) aras\u0131ndaki UHF TV kanallar\u0131n\u0131 almas\u0131n\u0131 sa\u011flar.<\/span><\/span><\/p>\n

Al\u0131nan UHF sinyali, y\u00fcksek ge\u00e7i\u015fli bir filtreden ge\u00e7erek \u00e7ift kap\u0131l\u0131 bir MOSFET transist\u00f6r BF998 olan a\u015fa\u011f\u0131 d\u00f6n\u00fc\u015f\u00fcm mikserinin Gate1’ine iletilir. Mikserin \u00e7\u0131k\u0131\u015f\u0131nda, d\u00f6n\u00fc\u015ft\u00fcr\u00fcc\u00fc ile IC-7000’in Ant2’si aras\u0131nda 50 ohm’luk bir koaksiyel kablo kullan\u0131m\u0131na olanak tan\u0131yan geni\u015f bantl\u0131 bir toroid (2 x 10 tur) bulunur.<\/span><\/span><\/p>\n

Mikserin Gate2’sine 432 MHz Yerel Osilat\u00f6r sinyali enjekte edilir. LO seviyesi, en iyi performans ve \u00e7\u0131k\u0131\u015fta daha az parazit i\u00e7in R* ile ayarlanabilir.<\/span><\/span><\/p>\n

Yerel Osilat\u00f6r, bir frekans \u00e7arpan\u0131 kullan\u0131r. 144 MHz’e (BF240) kadar \u00fc\u00e7 ile \u00e7arp\u0131lm\u0131\u015f 48 MHz’lik bir kristale dayan\u0131r. Ard\u0131ndan, 144 MHz sinyali tekrar \u00fc\u00e7 ile \u00e7arp\u0131larak 432 MHz’e (BFR92) kadar y\u00fckseltilir. 432 MHz sinyalinin harmoniklerden veya alt harmoniklerden ar\u0131nd\u0131r\u0131lm\u0131\u015f olmas\u0131 gerekir. Sinyali temizlemek i\u00e7in bir mikro \u015ferit bant ge\u00e7iren filtre kullan\u0131l\u0131r. D\u00fc\u015f\u00fck empedansl\u0131 bir \u00e7\u0131k\u0131\u015f, LO sinyalini al\u0131p miksere g\u00f6ndermek i\u00e7in kullan\u0131l\u0131r.<\/span><\/span><\/p>\n

Bu t\u00fcr LO’lar frekans \u00e7arpanlar\u0131 kulland\u0131\u011f\u0131ndan, \u00e7ok fazla istenmeyen parazit \u00fcretir (ki bunlar miksere gidebilir). Bu nedenle, metal bir kasada \u00e7ok iyi korunmas\u0131 pek tavsiye edilmez.<\/span><\/span><\/p>\n

Genellikle UHF TV kanallar\u0131 60. kanala (783 MHz) kadar \u00e7\u0131kar, ki bu zaten \u00e7ok nadir kullan\u0131l\u0131r. 44. kanaldan (657 MHz) daha y\u00fcksek kanallar almak istiyorsan\u0131z, 48 MHz yerine farkl\u0131 bir kristal kullanabilirsiniz (ki bu da tam olarak 48 MHz olmas\u0131 zorunlu de\u011fildir).<\/span><\/span><\/p>\n

\u00d6rne\u011fin, 53 MHz’lik bir \u00fcst ton kristali (eski \u00e7ift y\u00f6nl\u00fc VHF telsizlerde \u00e7ok yayg\u0131n bir kristal) kullan\u0131rsan\u0131z, a\u015fa\u011f\u0131 d\u00f6n\u00fc\u015ft\u00fcr\u00fclm\u00fc\u015f al\u0131m band\u0131 517 MHz ile 702 MHz (Ch27 ile Ch50) aras\u0131nda olacakt\u0131r. Bu durumda, LO \u00e7\u0131k\u0131\u015f mikro \u015ferit bant ge\u00e7i\u015f filtresinin biraz ayarlanmas\u0131 gerekir.<\/span><\/span><\/p>\n

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\"\"<\/p>\n","protected":false},"excerpt":{"rendered":"

IC-7000, TV ekran\u0131 al\u0131m \u00f6zelli\u011fine sahip ve bu da g\u00fczel bir \u015fey. Ne yaz\u0131k ki ICOM, TV’yi yaln\u0131zca 40MHz ile 225MHz (185MHz aral\u0131\u011f\u0131) aras\u0131ndaki VHF […]<\/p>\n","protected":false},"author":1,"featured_media":221,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,5],"tags":[],"class_list":["post-220","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hamrad","category-hf-projects"],"_links":{"self":[{"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/wp\/v2\/posts\/220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ta9ea.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=220"}],"version-history":[{"count":0,"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/wp\/v2\/posts\/220\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ta9ea.com\/index.php?rest_route=\/"}],"wp:attachment":[{"href":"https:\/\/ta9ea.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ta9ea.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ta9ea.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}