{"id":159,"date":"2001-10-01T08:01:53","date_gmt":"2001-10-01T08:01:53","guid":{"rendered":"https:\/\/satelit.cz\/?p=159"},"modified":"2001-10-01T08:01:53","modified_gmt":"2001-10-01T08:01:53","slug":"mikrovlnne-monoliticke-zesilovace-hp-ii","status":"publish","type":"post","link":"https:\/\/satelit.cz\/?p=159","title":{"rendered":"Mikrovlnn\u00e9 monolitick\u00e9 zesilova\u010de HP – II"},"content":{"rendered":"

P\u0159ed n\u011bkolika dny jsem se dostal k probl\u00e9mu s opravou jedn\u00e9 bezdr\u00e1tov\u00e9 karty v p\u00e1smu 2,4 GHz. Jednalo se o kartu PROXIM Symphony, kter\u00e1 po bou\u0159ce vykazovala z\u00e1vadu v p\u0159ij\u00edmac\u00ed \u010d\u00e1sti. Proto\u017ee \u0161lo ji\u017e o opakovanou z\u00e1vadu a bohu\u017eel to ji\u017e ne\u0161lo vy\u0159e\u0161it reklamac\u00ed, rozhodl jsem se o amat\u00e9rskou opravu.
\nP\u0159edem je t\u0159eba podotknout, \u017ee VF vstup karty nen\u00ed chr\u00e1n\u011bn \u017d\u00c1DN\u00ddM zp\u016fsobem a k zni\u010den\u00ed karty doch\u00e1z\u00ed i v p\u0159\u00edpadech, kdy ostatn\u00ed za\u0159\u00edzen\u00ed v dann\u00e9m m\u00edst\u011b (BreezCom, Orinoko, Cabletron ..) pracuj\u00ed bez probl\u00e9m\u016f. Ke zni\u010den\u00ed jedn\u00e9 karty do\u0161lo dokonce i p\u0159i pou\u017eit\u00ed bleskojistky na principu zkratovac\u00edho veden\u00ed, kter\u00e9 by m\u011blo zajistit na vstupu trvale nulov\u00fd stejnosm\u011brn\u00fd potenci\u00e1l. Ale ji\u017e k vlastn\u00ed konstrukci Symphony karty. Z\u00e1klad tvo\u0159\u00ed mezifrekven\u010dn\u00ed p\u0159ij\u00edma\u010d National LMX2240<\/a>, kter\u00fd spolu se vstupn\u00edm MMIC HP MGA-87563<\/a> a v\u00fdstupn\u00edm MMIC HP MGA-83563<\/a> tvo\u0159\u00ed celou vysokofrekcven\u010dn\u00ed \u010d\u00e1st p\u0159ij\u00edma\u010de. K p\u0159ep\u00edn\u00e1n\u00ed mezi vys\u00edl\u00e1n\u00edm a p\u0159\u00edjmem jsou pou\u017eity diody HP HSMP-3894<\/a>. Z\u00e1vadu jsem napoprv\u00e9 odhadl ve vstupn\u00edm obvodu MGA-87563<\/a> a za\u010dal jsem jej sh\u00e1n\u011bt. Bohu\u017eel se mi nikde nepoda\u0159ilo sehnat kusov\u00e9 mno\u017estv\u00ed a\u017e v GM-elektronicu<\/a> m\u011bli podobn\u00fd obvod MGA-86563<\/a>, kter\u00fd m\u00e1 bohu\u017eel jin\u00e9 zapojen\u00ed v\u00fdvod\u016f a o 10 dB v\u011bt\u0161\u00ed zisk. Za cenu cca 120,- K\u010d jsem si jich hned objednal n\u011bkolik kus\u016f, p\u0159idal jsem je\u0161t\u011b BFR-92, kter\u00e9 jsou jako n\u00e1sleduj\u00edc\u00ed aktivn\u00ed prvek za obvodem, PIN diody HP a pro dal\u0161\u00ed konstrukce je\u0161t\u011b v\u00fdkonov\u00fd MGA-83563<\/a>. Cel\u00e1 v\u00fdm\u011bna prob\u011bhla bez probl\u00e9m\u016f, jen bylo t\u0159eba obvod nap\u00e1jet „na z\u00e1da“ a zajistit nap\u00e1jen\u00ed, kter\u00e9 je zde na rozd\u00edl od p\u016fvodn\u00edho IC na v\u00fdstupn\u00edm v\u00fdvodu. Samoz\u0159ejm\u011b je t\u0159eba db\u00e1t na to, \u017ee nap\u00e1jec\u00ed nap\u011bt\u00ed je po dobu vys\u00edl\u00e1n\u00ed vyp\u00edn\u00e1no a je nutn\u00e9 pou\u017e\u00edt nap\u00e1jen\u00ed z p\u016fvodn\u00edho obdvodu. K oprav\u011b m\u011b inspirovala vynikaj\u00edc\u00ed str\u00e1nka Josepha N9ZIA<\/a>, kde jsem nalezl celou \u0159adu u\u017eite\u010dn\u00fdch informac\u00ed a \u010d\u00e1ste\u010dn\u00e9 sch\u00e9ma VF \u010d\u00e1sti karty PROXIM<\/a>.
\nCel\u00e1 oprava m\u011b p\u0159ivedla na my\u0161lenku pou\u017eit\u00ed t\u011bchto levn\u00fdch a dostupn\u00fdch obvod\u016f v transceiveru pro 13 a 9 cm, ale jak to cel\u00e9 dopadne to bude a\u017e v dal\u0161\u00edm \u010dl\u00e1nku \ud83d\ude42<\/p>\n

MMIC HP \u0159ady MGA-8×563<\/p>\n

MGA-81563<\/a>
\nMGA-82563<\/a>
\nMGA-83563<\/a>
\nMGA-85563<\/a>
\nMGA-86563<\/a>
\nMGA-87563<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

P\u0159ed n\u011bkolika dny jsem se dostal k probl\u00e9mu s opravou jedn\u00e9 bezdr\u00e1tov\u00e9 karty v p\u00e1smu 2,4 GHz. Jednalo se o kartu PROXIM Symphony, kter\u00e1 po bou\u0159ce vykazovala z\u00e1vadu v p\u0159ij\u00edmac\u00ed \u010d\u00e1sti. Proto\u017ee \u0161lo ji\u017e o opakovanou z\u00e1vadu a bohu\u017eel to ji\u017e ne\u0161lo vy\u0159e\u0161it reklamac\u00ed, rozhodl jsem se o amat\u00e9rskou opravu. P\u0159edem je t\u0159eba podotknout, \u017ee…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[5],"tags":[],"class_list":["post-159","post","type-post","status-publish","format-standard","hentry","category-kontrukce-tipy-bastleni"],"_links":{"self":[{"href":"https:\/\/satelit.cz\/index.php?rest_route=\/wp\/v2\/posts\/159","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/satelit.cz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/satelit.cz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/satelit.cz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/satelit.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=159"}],"version-history":[{"count":0,"href":"https:\/\/satelit.cz\/index.php?rest_route=\/wp\/v2\/posts\/159\/revisions"}],"wp:attachment":[{"href":"https:\/\/satelit.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=159"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/satelit.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=159"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/satelit.cz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=159"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}