ʻO ka haku mele a me ke kumu hana o ka microphone condenser electret

Poalua Dec 21 21:38:37 CST 2021

Aia ka microphone electret i ka hoʻololi uila acoustic a me ka hoʻololi impedance.ʻO ka mea nui o ka hoʻololi acoustoelectric ka diaphragm electret.He kiʻi kiʻiʻoniʻoni lahilahi loa ia, kahi e hoʻoheheʻe ʻia ai kahi kiʻi gula maʻemaʻe ma kekahi ʻaoʻao.A laila, ma hope o ka electret o ke kahua uila uila kiʻekiʻe, aia nā uku anisotropic ma nā ʻaoʻao ʻelua.ʻO ka ʻili gula i hoʻoheheʻe ʻia o ka diaphragm aia i waho a pili pū me ka pūpū metala.Hoʻokaʻawale ʻia ka ʻaoʻao ʻē aʻe o ka diaphragm mai ka pā metala e kahi apo lining insulating lahilahi.Ma kēia ala, ua hoʻokumu ʻia kahi capacitance ma waena o ke kiʻi gula evaporated a me ka pā metala.Ke hālāwai ka diaphragm electret i ka vibration acoustic, hoʻololi ke kahua uila ma nā ʻaoʻao ʻelua o ka capacitor, e hopena ana i kahi voli ʻokoʻa e ʻokoʻa me ka hoʻololi ʻana o ka nalu acoustic.He liʻiliʻi ka capacitance ma waena o ka diaphragm electret a me ka pā metala, ma ke ʻano he ʻumi o PF.No laila, kiʻekiʻe loa kona waiwai impedance (XC = 1 / 2 ~ TFC), ma kahi o ʻumi o megaohms a ʻoi aku paha.ʻAʻole hiki ke hoʻohālikelike ʻia kēlā impedance kiʻekiʻe me ka mea hoʻonui leo.No laila, hoʻopili ʻia kahi transistor hopena pānaʻi i loko o ka microphone no ka hoʻohuli impedance.Hōʻike ʻia ʻo FET e ka impedance hoʻokomo kiʻekiʻe a me ka helu haʻahaʻa haʻahaʻa.ʻO ka FET maʻamau he ʻekolu mau electrodes: electrode hana (s), electrode grid (g) a me drain electrode (d).Ma ʻaneʻi, hoʻohana ʻia kahi FET kūikawā me kahi diode ʻē aʻe ma waena o ke kumu o loko a me ka grid.ʻO ke kumu o ka diode e pale i ka FET mai ka hopena hōʻailona ikaika.Hoʻopili ʻia ka ʻīpuka o ka FET i kahi pā metala.Ma kēia ala, aia ʻekolu mau laina puka o ka microphone electret.'O ia ho'i, 'o ke kumu s he uea plastik polū, 'o ka lua D he uwea plastik 'ula'ula a me ka uwea pale pale e pili ana i ka pūpū metala.