Konzani Zomangira Zomangira Zopangira Ma Antennas

Posachedwapa, kuntchito, ndinali ndi kuthekera (kapena chofunikira) kuti ndipange chingwe chapang'onopang'ono cha mlongoti wa bay awiri. Komabe, ndinali ndi vuto. Ndidakhala pa intaneti zaka zingapo mmbuyo momwe ndingachitire izi pazochitika zanga za tinyanga, lero tsambalo linali litapita! Chotero ndinayenera kuzilingalira ndekha. Pambuyo pa maola ambiri ndikuyang'ana zolemba zanga (zosauka kwambiri), ndidazipeza.

Zomwe ndinali nazo zinali tinyanga tating'ono tozungulira tomwe timayenera kukhazikitsidwa ngati njira ya two bay antenna. Mlongoti uliwonse unali ndi kukana kwa 100 ohms. Pansipa pali zomwe ndabwera nazo, komanso zikuwoneka kuti zikugwira ntchito.

Mu mzere wopatsirana, monga coax, kusasunthika kwa katundu kumabwerezedwanso theka lililonse la wavelength. Chifukwa mlongoti uliwonse umasinthidwa kukhala 100 ohms pakugwedezeka, chomwe ndikufunika kuchita ndikuchepetsa utali wa coax ndendende mpaka utali wotalikirapo wa theka, komanso kuwalumikiza ku adapter ya Tee. Zomwe izi zimachitika ndikutenga zopinga ziwiri za 100 ohm za mlongoti uliwonse ndikuziyika mofanana. Mapeto ake ndi 50-ohm feed point, yomwe imandithandiza kulumikiza coax yanga ya 50-ohm pamasewera olondola.

Komabe, pali vuto limodzi. Coax ikapangidwa, pali kukana kwa 10% pakusinthasintha kwa liwiro la coax. Chifukwa chake ndikukhudzidwa, kungotenga kusinthika kwa liwiro la coax kumatha kukhala kovutirapo. Chifukwa chake ndidafunikira njira yoyezera kapena kuyitanira makulidwe achinsinsi a coax mpaka kuchulukitsa kwa theka la wavelength.

Pogwiritsa ntchito mbiri yakale, pansipa pali chithunzithunzi chomwe chikufanana ndi dongosolo la antenna lomwe ndinali kukhazikitsa. Zinthu ziwiri za coax zomwe ndimayenera kuchepetsa makamaka zimatchedwa "Phasing Harness":

Chifukwa chake zomwe ndinali nazo zinali Belden 8237 RG-8-U Kind coax. Izi zimakhala ndi kusinthasintha kwa 0.66 komanso kulepheretsa kwina kwa 52 ohms. Chifukwa chake potengera manambalawa, komanso katalikirana pakati pa tinyanga tiwiri ta tinyanga tating'onoting'ono, ndidasankha kugwiritsa ntchito makulidwe a coax omwe ndi 7 ndi XNUMX% kutalika kwa mafunde. Kwenikweni, iyi ndi njira yayitali kwambiri pazosowa zanga, komabe ndizabwino.

Izi ndi zomwe ndidabwera nazo, nditsanzira tinyanga zonse ziwiri tikagwedezeka ndi 100-ohm resistor. Chifukwa chake ndidapanga ma dummy anga mkati mwa cholumikizira chachimuna cha N, komanso kumbuyo kwa adaputala yamtundu wa N yachikazi. Kenako, ndidatsimikiza kutalika kwa mafunde amagetsi makumi asanu pagawo lachidutswa cha coax pogwiritsa ntchito njira yomatira:

L ( mainchesi) = (5904 * VelFactor) / Freq. (mHz)

Izi zikupatsirani kukula kwa gawo limodzi mwa magawo makumi asanu a kutalika kwa mawonekedwe. M'mikhalidwe yanga, ndinasankha 7 fifty wavelengths, kotero ndinawonjezera zotsatira ndi 7, kenako ndinawonjezera 15%. Tsambali ndi lalitali dala kotero kuti nditha kuyiyimitsa kuti igwirizane ndi zomwe mukufuna. Kumbali ina ya coax, ndinayika doko pamenepo. Mapeto enawo ndi malekezero amene ine ndidzachepetsedwa kukula. Chifukwa chake pamapeto pake, ndimayika adaputala pamenepo, komabe, sindimagulitsa, zomwe zili bwino kuyeza kwakanthawi kutalika kwake.

Nachi chithunzithunzi cha dongosolo langa loyesera pogwiritsa ntchito MFJ-209 antenna analyzer:

Yambani mayendedwe anu kusuntha pang'ono kuposa momwe mumafunira, kenako yambani kusuntha. Mukamayimba ma frequency angapo, mupezadi chinthu chomwe SWR imapita pafupifupi 1 mpaka 1. Nthawi zambiri ndimasuntha kangapo ku nadir ya SWR mbali zonse ziwiri. Izi zimatsimikizira kusanthula kolondola kwafupipafupi kwa coax. Chotsani kukhazikika.

Kenako, chepetsani coax ndi inchi, ndikubwereza masitepe omwe ali pamwambapa mpaka SWR ilowetsedwe pafupipafupi momwe tinyanga zanu zilili zamphamvu. Chitani izi pazinthu zonse ziwiri za coax, zomwe zimapanga chingwe choyambira.

Mukamaliza ndi zidutswa zonse ziwiri za coax, pakadali pano muli ndi zida zomaliza zomwe zakonzedwa kuti zizifanana ndendende ndi ma tinyanga anu.

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