Ukusetshenziswa Kwesihlungi esingu-21.4MHz ku-Walkie-Talkie Field

Ukusetshenziswa Kwesihlungi esingu-21.4MHz ku-Walkie-Talkie Field

Isihlungi esingu-21.4MHz sivamise ukusetshenziswa njengesihlungi se-intermediate frequency (IF) kubamukeli be-walkie-be-talkie, futhi ukusebenza kwaso kunquma ngokuqondile izinkomba ezimbili ezibalulekile-ze-talkies: ukukhetha nokuzwela.

Sizochaza ngokujulile kulezi zici ezilandelayo:

1. Iyini "I-Intermediate Frequency" ye-Walkie{1}}Talkie?

Ukuze kuzuzwe ukusebenza kahle, ama-walkie-talkies (kanye nabanye abamukeli be-superheterodyne) awakhulisi ngokuqondile futhi awehlise amasiginali atholiwe wefrikhwensi (RF) (isb, 400-470MHz). Kunalokho, zisebenzisa lezi zinyathelo ezilandelayo:① Ukuxuba: Isignali ye-RF yefrikhwensi ephezulu ixutshwa nesignali ekhiqizwe i-oscillator yendawo.② Isizukulwane Semvamisa Emaphakathi: Ngemva kokuxuba, isignali entsha enefrikhwensi engaguquki iyakhiqizwa, okuyifrikhwensi emaphakathi.③ UMA Ukukhulisa Nokuhlunga: Isignali eqinile ye-IF ehlungiwe iyisiginali eqinile.

Inzuzo yesakhiwo se-"superheterodyne" ukuthi iningi lenzuzo nokukhetha (ikhono lokuhlunga ukuphazanyiswa kwesiteshi esiseduze) kufinyelelwa ngalesi sigaba se-IF esinqunyiwe, okwenza umklamo wesifunda uzinze futhi usebenze kahle kakhulu.

2. Kungani 21.4MHz?

I-21.4MHz imvamisa ye-IF ejwayelekile edume kakhulu kumabhendi e-VHF/UHF (okuhlanganisa namabhendi asetshenziswa ama-walkie-talkies). Izizathu zayo zomlando nezobuchwepheshe zihlanganisa:

Uchungechunge lwezimboni zabantu abadala: Ngemvamisa engu-21.4MHz, kunenombolo enkulu yezihlungi ezivuthiwe, ezinzile, neziphansi-, ama-amplifiers, nezingxenye ezihlobene ezitholakalayo.

Ibhalansi phakathi kokusebenza nezindleko: Le mvamisa iphakeme ngokwanele ukucindezela ngempumelelo ukuphazamiseka kwesithombe (ukuphazamiseka okuvamile kokwamukela); ngesikhathi esifanayo, iphansi ngokwanele ukwenza lula ukuklama nokukhiqizwa kwezihlungi eziphezulu-Q (ikhwalithi yekhwalithi) (njengezihlungi zekristalu nezihlungi ze-ceramic).

Ifa lomlando: Lesi sibalo sisetshenziswe embonini yezokuxhumana amashumi eminyaka, futhi ama-walkie amaningi akudala-ama-talkie chips nezisombululo zakhelwe ngale mvamisa yamaphakathi.

3. Indima Eyinhloko Yesihlungi esingu-21.4MHz ku-Walkie-I-Talkies

Esigabeni se-21.4MHz IF, isihlungi "ungumgcini-sango" wangempela. Indima yayo ibalulekile:① Thuthukisa Ukukhetha

Umsebenzi: Ukukhethwa kubhekisela ekhonweni lomamukeli lokuhlukanisa isiginali oyifunayo kumasiginali amaningi futhi acindezele amasiginali okuphazamisa aseduze.

Indlela esebenza ngayo: Isihlungi esingu-21.4MHz sinejika lokuphendula lemvamisa engumqansa (imvamisa njengokuthi "udonga lwesitini"). Ivumela kuphela ingxenye yesiginali ene-21.4MHz njengendawo emaphakathi kanye nomkhawulokudonsa onembe kakhulu ukuthi idlule (isb, ±6.25kHz, ±7.5kHz, ±12.5kHz evame ukusetshenziswa ku-walkie-talkies, ehambisana nokuhlukana kweziteshi okuhlukile).

Umthelela ongokoqobo: Uma iziteshi zomsakazo ezimbili ezinamaza asondelene kakhulu zisakaza kanyekanye, i-walkie-talkie efakwe{1}}ukusebenza okuphezulu okungu-21.4MHz isihlungi ingakwazi ukuzwa kahle umsindo wesiteshi somsakazo esiqondiwe, kuyilapho icindezela ngempumelelo isignali yesinye isiteshi esiseduze ukuze igweme ukukhuluma. Ngaphandle kwalesi sihlungi noma ngesihlungi esingasebenzi kahle, uzozwa umsindo we-"channel crosstalk".

② Thuthukisa Ukuzwela

Umsebenzi: Ukuzwela kusho ikhono lomamukeli lokwamukela amasignali abuthakathaka.

Indlela esebenza ngayo: Ngaphambi kokukhulisa isignali ye-IF, isihlungi sisetshenziselwa ukuhlunga kukhishwe-{1}}kumsindo webhendi kanye nokuphazamiseka kuqala. Ngale ndlela, ukukhulisa okuyinhloko yisignali ewusizo "ehlanzekile" ngokwayo. Uma ukukhuliswa kwenziwa ngaphandle kokuhlunga, ukuphuma{{4}ku{5}}kumsindo webhendi nakho kuzokhuliswa, ngaleyo ndlela kuminze isignali esebenzayo ebuthakathaka.

Umthelela ongokoqobo: Ivumela i-walkie yakho-i-talkie ukuthi igcine ukuxhumana okuqondakalayo ngisho nakude noma ngamasignali abuthakathaka.

4. Izinhlobo zezihlungi ezingu-21.4MHz

Kuma-walkie-talkies, izihlungi ezijwayelekile ze-21.4MHz ikakhulukazi zihlanganisa lezi zinhlobo ezilandelayo:

Isihlungi se-Ceramic:

Izici: Izindleko eziphansi, usayizi omncane, ukwethembeka okuphezulu, futhi akukho ukulungiswa okudingekayo.

Izinhlelo zokusebenza: Isetshenziswa kakhulu phakathi-kuya{1}}kuzinkulumo{2}}eziphansi-ze-walkie{3}}, futhi ukusebenza kwayo kwanele ukuhlangabezana nezidingo eziningi ezivamile. Umkhawulokudonsa wayo kanye nesici somumo (inkomba yokulinganisa ukujula konqenqema lwesihlungi) ngokuvamile kubi kakhulu kunezihlungi zekristalu kodwa kungcono kakhulu kunezihlungi ze-LC.

Isihlungi seCrystal:

Izici: Inenani eliphakeme kakhulu le-Q, ngakho ukukhetha kuhle kakhulu, futhi isici somumo siseduze kakhulu nesimo esifanele.

Izinhlelo zokusebenza: Ngokuvamile zisetshenziswa-ezingxoxweni ezisezingeni eliphezulu-zezingxoxo noma izikhathi ezidinga amandla aphezulu kakhulu okulwa{2}}nokuphazamisa. Izindleko ziphakeme kunezihlungi ze-ceramic.