\u00c2m nh\u1ea1c ph\u00e1t t\u1eeb m\u00e1y CD (compact disc player: m\u00e1y h\u00e1t laze, m\u00e1y quay \u0111\u0129a compac) s\u1ed1ng \u0111\u1ed9ng h\u01a1n m\u00e1y caset (radio cassette rocorder). \u0110\u00f3 l\u00e0 nguy\u00ean l\u00ed v\u00e0 ph\u01b0\u01a1ng ph\u00e1p ghi \u00e2m v\u00e0 ph\u00e1t ti\u1ebfng c\u1ee7a m\u00e1y CD v\u00e0 caset kh\u00e1c h\u1eb3n nhau.<\/p>\n\n\n\n
M\u00e1y caset khi ghi v\u00e0 ph\u00e1t t\u00edn hi\u1ec7u \u00e2m thanh th\u00ec d\u00f9ng b\u0103ng t\u1eeb. B\u0103ng t\u1eeb \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh b\u1edfi d\u1ea3i b\u0103ng m\u1ecfng polyeste v\u00e0 v\u1eadt li\u1ec7u t\u1eeb t\u00ednh d\u1ea1ng b\u1ed9t ph\u1ee7 \u0111\u1ec1u tr\u00ean b\u1ec1 m\u1eb7t. M\u00e1y caset khi ghi t\u00edn hi\u1ec7u \u00e2m thanh tho\u1ea1t ti\u00ean th\u00f4ng qua \u1ed1ng n\u00f3i bi\u1ebfn \u0111\u1ed5i th\u00e0nh t\u00edn hi\u1ec7u d\u00f2ng \u0111i\u1ec7n t\u01b0\u01a1ng \u1ee9ng v\u1edbi n\u00f3 v\u00e0 ch\u1ea1y v\u00e0o cu\u1ed9n d\u00e2y trong \u0111\u1ea7u t\u1eeb ghi \u00e2m c\u1ee7a m\u00e1y caset. L\u00fac n\u00e0y d\u1ef1a v\u00e0o nguy\u00ean l\u00ed l\u00e0 \u0111i\u1ec7n trong c\u1ea3m \u1ee9ng \u0111i\u1ec7n t\u1eeb c\u00f3 th\u1ec3 sinh ra t\u1eeb m\u00e0 xung quanh cu\u1ed9n d\u00e2y s\u1ebd h\u00ecnh th\u00e0nh m\u1ed9t t\u1eeb tr\u01b0\u1eddng \u0111\u01b0\u1ee3c bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u1ee9ng v\u1edbi d\u00f2ng \u0111i\u1ec7n \u00e2m thanh. Khi b\u0103ng t\u1eeb ch\u1ea1y qua \u0111\u1ea7u t\u1eeb ghi \u00e2m theo chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a c\u01a1 c\u1ea5u chuy\u1ec1n \u0111\u1ed9ng th\u00ec v\u1eadt li\u1ec7u t\u1eeb t\u00ednh tr\u00ean b\u0103ng l\u1eadp t\u1ee9c b\u1ecb t\u1eeb h\u00f3a b\u1edfi t\u1eeb tr\u01b0\u1eddng bi\u1ebfn \u0111\u1ed5i xung quanh cu\u1ed9n d\u00e2y trong \u0111\u1ea7u t\u1eeb, v\u00e0 l\u01b0u l\u1ea1i tr\u00ean b\u0103ng t\u1eeb t\u00ednh (t\u1eeb d\u01b0) \u0111\u01b0\u1ee3c bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u1ee9ng v\u1edbi d\u00f2ng \u0111i\u1ec7n \u00e2m thanh. T\u1eeb d\u01b0 c\u00f3 t\u00e1c d\u1ee5ng ghi l\u1ea1i t\u00edn hi\u1ec7u \u00e2m thanh theo h\u00ecnh th\u1ee9c t\u1eeb h\u00f3a.<\/p>\n\n\n\n
Mu\u1ed1n ph\u00e1t l\u1ea1i t\u00edn hi\u1ec7u \u00e2m thanh th\u00ec ch\u1ec9 c\u1ea7n ph\u00e1t b\u0103ng t\u00edn hi\u1ec7u \u00e2m thanh \u0111\u00e3 ghi \u0111\u01b0\u1ee3c b\u1eb1ng \u0111\u1ea7u t\u1eeb ph\u00e1t ti\u1ebfng. D\u1ef1a v\u00e0o nguy\u00ean l\u00ed l\u00e0 t\u1eeb trong c\u1ea3m \u1ee9ng \u0111i\u1ec7n t\u1eeb c\u0169ng c\u00f3 th\u1ec3 sinh ra \u0111i\u1ec7n. T\u1eeb d\u01b0 tr\u00ean b\u0103ng t\u1eeb s\u1ebd sinh ra t\u00edn hi\u1ec7u d\u00f2ng \u0111i\u1ec7n \u0111\u01b0\u1ee3c bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u1ee9ng v\u1edbi t\u00edn hi\u1ec7u \u00e2m thanh trong cu\u1ed9n d\u00e2y c\u1ee7a \u0111\u1ea7u t\u1eeb ph\u00e1t ti\u1ebfng. Sau \u0111\u00f3 s\u1ebd khu\u1ebfch \u0111\u1ea1i t\u00edn hi\u1ec7u d\u00f2ng \u0111i\u1ec7n qua b\u1ed9 khu\u1ebfch \u0111\u1ea1i c\u1ee7a m\u00e1y caset v\u00e0 r\u1ed3i ph\u00e1t ra t\u00edn hi\u1ec7u \u00e2m thanh t\u1eeb m\u00e1y ph\u00e1t thanh.<\/p>\n\n\n\n
Trong qu\u00e1 tr\u00ecnh m\u00e1y caset ghi v\u00e0 ph\u00e1t t\u00edn hi\u1ec7u \u00e2m thanh n\u00f3i tr\u00ean th\u00ec caset \u0111\u00e3 \u00e1p d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p t\u01b0\u01a1ng t\u1ef1: d\u00f2ng \u0111i\u1ec7n trong cu\u1ed9n d\u00e2y v\u00e0 t\u1eeb d\u01b0 tr\u00ean b\u0103ng t\u1eeb \u0111\u1ec1u l\u00e0 s\u1ef1 bi\u1ebfn \u0111\u1ed5i c\u1ee7a t\u00edn hi\u1ec7u ti\u1ebfng n\u00f3i t\u01b0\u01a1ng t\u1ef1. Do ch\u1ecbu \u1ea3nh h\u01b0\u1edfng c\u1ee7a m\u00f4i tr\u01b0\u1eddng b\u00ean ngo\u00e0i v\u00e0 \u0111i\u1ec1u ki\u1ec7n v\u1eadt l\u00ed, mu\u1ed1n b\u1eaft ch\u01b0\u1edbc gi\u1ed1ng nh\u01b0 th\u1eadt s\u1ebd c\u00f3 kh\u00f3 kh\u0103n nh\u1ea5t \u0111\u1ecbnh. B\u1edfi v\u1eady m\u00e0 g\u00e2y n\u00ean hi\u1ec7n t\u01b0\u1ee3ng kh\u00f4ng th\u1eadt, nh\u1ea5t l\u00e0 v\u1edbi \u00e2m th\u1ea5p v\u00e0 \u00e2m cao th\u00ec c\u00e0ng th\u1ea5y r\u00f5. Do t\u00edn hi\u1ec7u \u00e2m nh\u1ea1c c\u00f3 d\u1ea3i t\u1ea7n s\u1ed1 r\u1ed9ng m\u00e0 khi ghi v\u00e0 ph\u00e1t b\u0103ng s\u1ebd x\u1ea3y ra \u0111i\u1ec1u kh\u00f4ng hay l\u00e0 \u00e2m cao th\u00ec ngh\u00e8o, \u00e2m tr\u1ea7m c\u0169ng thi\u1ebfu. L\u1ea1i n\u1eefa, \u0111a s\u1ed1 m\u00e1y ph\u00e1t thanh v\u00e0 ph\u00f3ng \u0111\u1ea1i tr\u00ean m\u00e1y caset th\u00edch \u1ee9ng r\u1ea5t k\u00e9m v\u1edbi t\u00edn hi\u1ec7u \u00e2m nh\u1ea1c thu\u1ed9c ph\u1ea1m vi bi\u1ebfn \u0111\u1ed5i t\u1ea7n s\u1ed1 r\u1ed9ng. \u00c2m nh\u1ea1c ph\u00e1t l\u1ea1i th\u01b0\u1eddng hi\u1ec7u qu\u1ea3 kh\u00f4ng l\u00e0m ta v\u1eeba l\u00f2ng. Ngo\u00e0i ra, khi b\u0103ng t\u1eeb ghi v\u00e0 ph\u00e1t th\u00ec ph\u1ea3i chuy\u1ec3n \u0111\u1ed9ng li\u00ean t\u1ee5c, g\u00e2y ra s\u1ef1 ma s\u00e1t ti\u1ebfp x\u00fac v\u1edbi c\u01a1 c\u1ea5u truy\u1ec1n \u0111\u1ed9ng v\u00e0 \u0111\u1ea7u t\u1eeb, l\u00e0m cho b\u1ed9t t\u1eeb b\u1ecb bung ra, t\u1ea1o n\u00ean t\u1ea1p \u00e2m r\u00edt, \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn hi\u1ec7u qu\u1ea3 \u00e2m h\u01b0\u1edfng.<\/p>\n\n\n\n
M\u00e1y CD khi ghi v\u00e0 ph\u00e1t l\u1ea1i t\u00edn hi\u1ec7u \u00e2m thanh th\u00ec s\u1eed d\u1ee5ng \u0111\u0129a h\u00e1t laze, t\u1ee9c l\u00e0 \u0111\u0129a h\u00e1t CD. \u0110\u0129a CD l\u00e0 \u0111\u0129a h\u00ecnh tr\u00f2n c\u00f3 c\u1ed1t l\u00e0m b\u1eb1ng polycacbonat (g\u1ecdi t\u1eaft l\u00e0 PC) b\u1ec1 m\u1eb7t tr\u00e1ng m\u1ed9t l\u1edbp m\u00e0ng m\u1ecfng kim lo\u1ea1i m\u00e0u tr\u1eafng b\u1ea1c. L\u00fac ghi \u00e2m, t\u00edn hi\u1ec7u \u00e2m thanh tho\u1ea1t ti\u00ean s\u1ebd bi\u1ebfn th\u00e0nh d\u00f2ng \u0111i\u1ec7n \u00e2m thanh t\u01b0\u01a1ng \u1ee9ng qua \u1ed1ng n\u00f3i (micro) r\u1ed3i \u0111\u00f3 bi\u1ebfn \u0111\u1ed5i th\u00e0nh d\u00f2ng \u0111i\u1ec7n m\u1ea1ch xung \u0111\u01b0\u1ee3c bi\u1ec3u th\u1ecb b\u1eb1ng t\u1eebng nh\u00f3m s\u1ed1 0 v\u00e0 1 (0 bi\u1ec3u th\u1ecb kh\u00f4ng c\u00f3 d\u00f2ng \u0111i\u1ec7n, 1 bi\u1ec3u th\u1ecb c\u00f3 d\u00f2ng \u0111i\u1ec7n) trong m\u1ed9t thi\u1ebft b\u1ecb g\u1ecdi l\u00e0 “thi\u1ebft b\u1ecb chuy\u1ec3n \u0111\u1ed5i t\u01b0\u01a1ng t\u1ef1 – s\u1ed1” b\u1eb1ng vi\u1ec7c x\u1eed l\u00fd k\u1ef9 thu\u1eadt nh\u01b0 l\u1ea5y m\u1eabu, l\u01b0\u1ee3ng t\u1eed h\u00f3a, ghi m\u00e3 s\u1ed1. N\u00f3 c\u00f3 th\u1ec3 \u0111i\u1ec1u khi\u1ec3n thi\u1ebft b\u1ecb ph\u00e1t x\u1ea1 laze l\u00e0m cho laze ph\u00e1t ra khi c\u00f3 d\u00f2ng \u0111i\u1ec7n m\u1ea1ch xung, r\u1ed3i \u0111\u00f3 s\u1ebd h\u1eb1n l\u00ean m\u1ed9t l\u1ed7 l\u00f5m c\u1ef1c nh\u1ecf tr\u00ean \u0111\u0129a. S\u1ed1 l\u01b0\u1ee3ng l\u1ed7 l\u00f5m tr\u00ean \u0111\u0129a CD chu\u1ea9n c\u00f3 \u0111\u01b0\u1eddng k\u00ednh 12 cm c\u00f3 th\u1ec3 t\u1edbi 2,5 t\u1ec9 l\u1ed7. B\u1edfi v\u1eady c\u00f3 th\u1ec3 l\u01b0u tr\u1eef \u0111\u01b0\u1ee3c l\u01b0\u1ee3ng tin kh\u00e1 l\u1edbn. Th\u1eddi gian ghi v\u00e0 ph\u00e1t l\u1ea1i c\u00f3 th\u1ec3 k\u00e9o d\u00e0i 74 ph\u00fat. T\u00edn hi\u1ec7u \u00e2m thanh ghi tr\u00ean \u0111\u0129a b\u1eb1ng ph\u01b0\u01a1ng ph\u00e1p s\u1ed1 h\u00f3a n\u00e0y ch\u1ec9 l\u00e0 m\u1ed9t chu\u1ed7i l\u1ed7. Ch\u00fang kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi m\u00f4i tr\u01b0\u1eddng v\u00e0 \u0111i\u1ec1u ki\u1ec7n v\u1eadt l\u00ed, \u0111\u1ed9 th\u1eadt r\u1ea5t cao, g\u1ea7n nh\u01b0 kh\u00f4ng c\u00f3 ti\u1ebfng \u1ed3n. Do v\u1eady ta th\u1ea5y, v\u1ec1 ch\u1ea5t l\u01b0\u1ee3ng ghi ti\u1ebfng th\u00ec m\u00e1y CD \u0111\u00e3 h\u01a1n h\u1eb3n m\u00e1y caset r\u1ed3i.<\/p>\n\n\n\n
Khi m\u00e1y CD ph\u00e1t l\u1ea1i \u0111\u0129a th\u00ec ch\u00f9m tia \u00e1nh s\u00e1ng k\u00edch th\u00edch chi\u1ebfu l\u00ean c\u00e1c l\u1ed7 l\u00f5m c\u1ee7a \u0111\u0129a CD, c\u00f9ng v\u1edbi s\u1ef1 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a \u0111\u0129a, ch\u00f9m laze s\u1ebd \u0111\u01b0\u1ee3c ph\u1ea3n x\u1ea1 li\u00ean t\u1ee5c t\u1eeb nh\u1eefng l\u1ed7 l\u00f5m. Do ch\u00f9m \u00e1nh s\u00e1ng ph\u1ea3n x\u1ea1 c\u1ee7a ch\u00f9m laze t\u1eeb trong h\u1ed1 l\u00f5m v\u00e0 m\u1eb7t b\u1eb1ng kia c\u00f3 nh\u1eefng \u0111\u1eb7c tr\u01b0ng kh\u00e1c h\u1eb3n nhau, b\u1edfi v\u1eady, t\u1ea1i b\u1ed9 ti\u1ebfp nh\u1eadn quang s\u1ebd chuy\u1ec3n t\u1ea3i d\u00f2ng \u0111i\u1ec7n m\u1ea1ch xung \u1ee9ng v\u1edbi c\u00e1c s\u1ed1 0 v\u00e0 1, th\u00f4ng qua bi\u1ebfn \u0111\u1ed5i quang \u0111i\u1ec7n. R\u1ed3i \u0111\u00f3 l\u1ea1i ho\u00e0n nguy\u00ean th\u00e0nh d\u00f2ng \u0111i\u1ec7n \u00e2m thanh t\u1eeb thi\u1ebft b\u1ecb chuy\u1ec3n \u0111\u1ed5i s\u1ed1\/t\u01b0\u01a1ng t\u1ef1 (s\u1ed1\/t\u01b0\u01a1ng t\u1ef1). Trong qu\u00e1 tr\u00ecnh n\u00e0y, kh\u00f4ng b\u1ecb m\u00e9o m\u00f3 (th\u1ea5t ch\u00e2n) c\u0169ng kh\u00f4ng b\u1ecb m\u00e0i m\u00f2n b\u1edfi m\u00e1y. Ngo\u00e0i ra, b\u1ed9 khu\u1ebfch \u0111\u1ea1i v\u00e0 b\u1ed9 ph\u00e1t thanh g\u1eafn trong m\u00e1y CD ph\u1ea7n l\u1edbn \u0111\u1ec1u gi\u1eef \u0111\u01b0\u1ee3c \u0111\u1ed9 th\u1eadt cao, cho ph\u00e9p ph\u1ea1m vi bi\u1ebfn \u0111\u1ed5i t\u1ea7n s\u1ed1 c\u1ee7a t\u00edn hi\u1ec7u d\u00f2ng \u0111i\u1ec7n ch\u1ea1y qua c\u0169ng r\u1ea5t r\u1ed9ng r\u00e3i, b\u1eb1ng ph\u1eb3ng; bao ph\u1ee7 l\u00ean c\u1ea3 ph\u1ea1m vi \u00e2m v\u1ef1c nghe \u0111\u01b0\u1ee3c c\u1ee7a con ng\u01b0\u1eddi v\u00e0 c\u00f3 th\u1ec3 t\u00e1i hi\u1ec7n ch\u00e2n th\u1ef1c hi\u1ec7u qu\u1ea3 \u00e2m h\u01b0\u1edfng khi ghi \u00e2m.<\/p>\n\n\n\n
Do \u00e2m nh\u1ea1c m\u00e1y CD ph\u00e1t ra s\u1ed1ng \u0111\u1ed9ng h\u01a1n nhi\u1ec1u so v\u1edbi caset m\u00e0 trong nh\u1eefng tr\u01b0\u1eddng h\u1ee3p \u0111\u00f2i h\u1ecfi ph\u1ea3i c\u00f3 ch\u1ea5t l\u01b0\u1ee3ng ph\u00e1t \u00e2m nh\u1ea1c cao ng\u01b0\u1eddi ta \u0111\u1ec1u s\u1eed d\u1ee5ng m\u00e1y CD.<\/p>\n\n\n\n
T\u1eeb kh\u00f3a: CD (m\u00e1y h\u00e1t laze); Caset; Laze.<\/p>\n","protected":false},"excerpt":{"rendered":"
\u00c2m nh\u1ea1c ph\u00e1t t\u1eeb m\u00e1y CD (compact disc player: m\u00e1y h\u00e1t laze, m\u00e1y quay \u0111\u0129a compac) s\u1ed1ng \u0111\u1ed9ng h\u01a1n m\u00e1y caset (radio cassette rocorder). \u0110\u00f3 l\u00e0 nguy\u00ean l\u00ed v\u00e0 ph\u01b0\u01a1ng ph\u00e1p ghi \u00e2m v\u00e0 ph\u00e1t ti\u1ebfng c\u1ee7a m\u00e1y CD v\u00e0 caset kh\u00e1c h\u1eb3n nhau. M\u00e1y caset khi ghi v\u00e0 ph\u00e1t t\u00edn hi\u1ec7u \u00e2m thanh th\u00ec […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15,13],"tags":[],"class_list":["post-10406","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-tin-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10406","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=10406"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10406\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=10406"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=10406"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=10406"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}