Beddelka Impedance: Sida 8 Ω Afhayeenka u noqda 5 kΩ

Haddii aad waligaa kor u rujisay cod-weyneeye tuubo duug ah, waxaad u isticmaashay transformer hab aan shaqo ku lahayn u bedelida korantada gidaarka 12 V. Shaqadeedu waxay ahayd inay samayso cod-baahiye yar oo 8 Ω ah "u eg" 5,000 Ω rarka tuubada faakuumka. Khiyaamadaas waxaa loo yaqaan impedance matching, transformer-kuna waa mid ka mid ah siyaabaha ugu waxtarka badan ee loo sameeyo.

Kuwa Bilawga ah: Waa maxay Caqabadda Macnaheeda

Ka fakar impedance sida "cadaadiska dhabarka" wareeggu siinaya hadda beddelka. Ilaha kacsanaanta sare leh, sida wareegga saxanka ee tuubada, waxa uu u dhaqmaa sida tuubo dhuuban oo isku dayaya in ay biyaha ku riixdo tuubo furan: inta badan tamarta dib ayay u soo noqotaa. Culays hooseeya, sida cod-baahiyaha, wuxuu u dhaqmaa sida tuubadaas ballaaran ee furan. Haddii aad si toos ah ugu xirto, awood aad u yar ayaa gaadhaysa afhayeenka.

Injineerada ayaa tan ku qeexaya fikradda wareejinta awoodda ugu badan: isha ayaa keenta awoodda ugu badan marka ay aragto culeys la siman (ama isku xiraya) caqabadeeda gudaha. Transformer-ku waxa uu buuxiyaa baahidaas iyada oo aan tamarta ku lumin kulayl ahaan.

Waa maxay sababta sharciga Square uu muhiim u yahay

Saamiga wareegtada beddelka waa a = Np / Ns , tirada wareegyada aasaasiga ah waxaa loo qaybiyaa wareegyada sare. Dhammaanteen waan ognahay korontadu inay kor u kacdo ama hoos u dhigto saamigaas. Wax yar oo cad ayaa ah waxa ku dhaca xannibaadda Sababtoo ah isbeddelada hadda ee jihada ka soo horjeeda, culeyska culeyska ee ka muuqda kan hoose ayaa lagu dhuftey afargeeska saamiga leexashada:

Z_reflected = a² × Z_load

ama, ku qoran leexo:

Z_reflected = (Np / Ns)² × Z_load

Marka loo eego tixraacyada injineernimada, tani waa isla'egta dhexe ee isbarbardhigga isdhaafsiga. A 25:1 transformer ayaa haddaba ka tarjumaysa 8 Ω ku hadla sida 25² × 8 = 5,000 Ω isha. A 2:1 Transformer wuxuu ka tarjumayaa anteeno 50 Ω ah sida culeys 200 Ω ah, iyo wixii la mid ah (Velatron; koronto-dhaliyaha).

Halka aad kula kulanto

Transformers wax soo saarka maqalku waa tusaalaha caadiga ah. Tuubbada 6V6GT waxay doonaysaa qiyaastii 5,000 Ω culayska saxan, laakiin ku hadlahu waa 4 Ω ama 8 Ω. Xalku waa 25: 1 wax soo saarka maqalka. Calaamada koowaad ee 100 V RMS, ka sare wuxuu keenaa ilaa 4 V RMS 8 Ω ku hadla, isaga oo siinaya qiyaastii 2 W ee awooda codka (electricalflux). Cod-weyneeye kala duwan, waxaad si fudud u xallinaysaa a = √(Z_source / Z_load) , ka dib dooro tirinta bobbin ee ugu dhow.

Isla fikradda ayaa ka muuqata inta jeer ee raadiyaha. RF baluns iyo transformers-ku-habboon waxay isku xiraan anteenooyinkooda iyo xadhkaha gudbinta ee cilladaha dabeecadaha kala duwan - tusaale ahaan, ku habboon anteenada 200 Ω iyo gudbiyaha 50 Ω oo leh 2: 1 transformer - markaa tamarta muuqata ma dhaawacayso heerka korantada (Alaabooyinka ISL; Velatron).

Digniin Injineernimo

Transformer-ka maqalku ma noqon karo koronto cad oo 50/60 Hz ah. Marxaladaha wax soo saarka vacuum-tube waxay riixaan eexda DC ee hadda socota iyada oo loo marayo asaasiga. La'aanteed farqiga hawo ee xudunta u ah, goobtaas DC waxay buuxisaa xayndaabyada, duminta inductance iyo qalloocinta codka (electricalflux). Transformers-yada wax-soo-saarka maqalka ayaa sidaas darteed nashqadaha silikoon-birta kala-duwan. Marka la joogo RF, ferrite ama birta budada ah waxay beddelaan birta dahaadhka ah si ay khasaaraha asaasiga ah hoos ugu dhigaan boqollaal kilohertz ilaa megahertz (electricalflux).

Transformers-yada dhabta ah waxay sidoo kale leeyihiin iska caabin dabaylo leh, inductance dareere ah, awood isdhexgal ah, iyo hadda magnetizing. Ku dulin-ku-nooleyaashaasi waxay xaddidaan xajmigooda waxayna dejiyaan saamiga impedance ee ugu yar ee waxtarka leh. Haddii saamiga uu noqdo mid aad u weyn, hal qayb transformer ayaa noqonaysa khasaare; nashqadaha baladhan ka dib waxay adeegsadaan qaybo badan ama transformers-ka khadka gudbinta (Shan la heli karo).

Faham-xumada Guud / Xaqiiqda Madadaalada

Fikrad khaldan: "Transformer-ku kaliya wuxuu beddelaa tamarta; ma beddelo xannibaadyada." Taasi waxay seegtay sharciga square. Miisaanka korantada oo leh N, laakiin miisaan la'aanta N² sababtoo ah labadaba tamarta iyo hadda waa la beddelaa.

Xaqiiqda xiisaha leh: 1: 1 transformer-ka go'doominta wuxuu ku beddelaa xannibaadda 1², taas oo aan haba yaraatee waxba iska beddelin - weli aad bay faa'iido u leedahay sababtoo ah waxay jebisaa wareegyada dhulka waxayna bixisaa go'doomin galvanic. Dhanka kale, isku-dhafka taleefanka 600 Ω ee hore wuxuu ahaa qalab maqal ah oo taxadir leh loo qaybiyay kaasoo u oggolaanaya hal lammaane oo fiilo ah inay wada sheekaystaan ​​labada dhinac. Mar kasta oo amp gitaarka tuubada uu ka dhex guuxo cod-bixiyaha, transformer-ku waxa uu si degan u dhigayaa in is-maan-dhaafku meesha ka baxo.