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        <div id="content-top1">Page 4 - thong bao</div>
        <div id="content-top2">P. 4</div>
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    <pre style="white-space:pre-line"><code>DuyÃªn Ná»£ Truyá»n Tin - Há»“i KÃ½ - Nguyá»…n Huy HÃ¹ng

cho coi cÃ¡ch há» dÃ¹ng Ä‘á»‘ng lá»­a vÃ  táº¥m da thÃº váº­t Ä‘á»ƒ táº¡o cÃ¡c bá»¥m khÃ³i thÃ´ng tin vá»›i nhau
nhÆ° tháº¿ nÃ o.

         Äáº¿n táº­n Tháº¿ ká»· 20, chÃºng ta cÅ©ng cÃ²n tháº¥y cÃ¡c lÃ ng xÃ£ Viá»‡t Nam dÃ¹ng MÃ• TRE
hoáº·c Gá»– Ä‘á»ƒ bÃ¡o tin cho nhau giá» cáº§m canh Ä‘Ãªm hoáº·c hiá»‡u bÃ¡o Ä‘á»™ng cÃ³ cÆ°á»›p xÃ¢m nháº­p
khu vá»±c, giá»¯a cÃ¡c tráº¡m tuáº§n Ä‘inh canh gÃ¡c táº¡i cÃ¡c xÃ³m trong cÃ¹ng má»™t lÃ ng. Quáº§n chÃºng
vÃ¹ng Ä‘á»“ng báº±ng sÃ´ng Há»“ng (Báº¯c Viá»‡t) cÃ²n dÃ¹ng TRá»NG lá»›n táº¡o Ä‘Æ°á»£c tiáº¿ng vang lan Ä‘i
tháº­t xa, Ä‘á»ƒ bÃ¡o tin giá»¯a cÃ¡c tráº¡m canh Ä‘Ãª trong mÃ¹a nÆ°á»›c lÅ© lá»¥t. NgoÃ i ra, TRá»NG cÅ©ng
Ä‘Æ°á»£c dÃ¹ng Ä‘á»ƒ bÃ¡o hiá»‡u cho quáº§n chÃºng biáº¿t giá» khai máº¡c cÃ¡c ká»³ há»p lÃ ng, lá»… há»™i, hay hÃ¡t
tuá»“ng hÃ¡t bá»™i, Ä‘á»ƒ mÃ  giáº¯t nhau Ä‘i tham dá»±. NÆ¡i thÃ nh thá»‹ dÆ°á»›i thá»i PhÃ¡p thuá»™c trÆ°á»›c
1945, Ä‘Ãªm Ä‘Ãªm chÃºng ta cÅ©ng thÆ°á»ng nghe tiáº¿ng KáººNG cáº§m canh, hoáº·c bÃ¡o Ä‘á»™ng cÃ³ tÃ¹
vÆ°á»£t ngá»¥c, giá»¯a cÃ¡c tráº¡m lÃ­nh canh gÃ¡c tÃ¹ ngá»“i trÃªn cÃ¡c chÃ²i lÃ´ cá»‘t cao táº¡i cÃ¡c gÃ³c tÆ°á»ng
chung quanh nhÃ  khÃ¡m lá»›n giam tÃ¹.

         TrÃªn toÃ n tháº¿ giá»›i, suá»‘t tá»« buá»•i xa xÆ°a cho Ä‘áº¿n Äá»‡ Nháº¥t Tháº¿ Chiáº¿n, táº¥t cáº£ cÃ¡c
nÆ°á»›c trÃªn 5 chÃ¢u Lá»¥c Ä‘á»‹a Ä‘á»u dÃ¹ng TRá»NG vÃ  KÃˆN Ä‘á»ƒ chuyá»ƒn lá»‡nh cho quÃ¢n sÄ©, biáº¿t giá»
giáº¥c thá»©c, ngá»§, táº­p há»p, nghá»‰ viá»‡c táº¡i cÃ¡c doanh tráº¡i, vÃ  tiáº¿n quÃ¢n, thá»‘i lui nÆ¡i chiáº¿n
trÆ°á»ng. Hiá»‡n nay cÃ¡c tráº¡i lÃ­nh cá»§a PhÃ¡p vÃ  Hoa Ká»³ váº«n cÃ²n dÃ¹ng KÃˆN bÃ¡o thá»©c, ngá»§, vÃ 
máº·c niá»‡m trong nhá»¯ng buá»•i lá»… an tÃ¡ng hoáº·c chiÃªu há»“n Tá»­ SÄ©. DÄ© nhiÃªn ngÆ°á»i ta pháº£i quy
Ä‘á»‹nh cÃ¡c khÃºc nháº¡c vá»›i nhá»¯ng Ã¢m Ä‘iá»‡u KÃˆN khÃ¡c nhau, vÃ  nhá»¯ng há»“i TRá»NG khÃ¡c nhau
Ä‘á»ƒ phÃ¢n biá»‡t má»—i loáº¡i tin tá»©c cáº§n truyá»n Ä‘áº¡t. BÃªn Ã‚u ChÃ¢u, ngÆ°á»i ta cÃ²n dÃ¹ng 2 chiáº¿c Cá»œ
nhá» máº§u tráº¯ng Ä‘á», cáº±m nÆ¡i 2 tay dÆ¡ lÃªn háº¡ xuá»‘ng theo má»™t quy Æ°á»›c riÃªng Ä‘á»ƒ lÃ m phÆ°Æ¡ng
tiá»‡n liÃªn láº¡c giá»¯a 2 tráº¡m truyá»n tin náº±m trong táº§m máº¯t nhÃ¬n Ä‘Æ°á»£c cá»§a con ngÆ°á»i. Nhá»¯ng
ngÆ°á»i Ä‘i thuyá»n, táº§u, lÃªnh Ä‘Ãªnh trÃªn biá»ƒn cáº£, ngoÃ i cÃ¡c Cá»œ nÃ³i trÃªn, ngÆ°á»i ta cÃ²n dÃ¹ng
má»™t loáº¡i gÆ°Æ¡ng pháº£n chiáº¿u Ã¡nh sÃ¡ng máº·t trá»i cÃ³ miáº¿ng che Ä‘Ã³ng má»Ÿ Ä‘Æ°á»£c, nháº±m thá»±c
hiá»‡n nhá»¯ng loáº¡i tÃ­n hiá»‡u ngáº¯n vÃ  dÃ i phá»‘i há»£p Ä‘á»ƒ biá»ƒu tÆ°á»£ng cho cÃ¡c máº©u tá»± La tinh
(Morse) Ä‘á»ƒ liÃªn láº¡c trao Ä‘á»•i tin tá»©c vá»›i nhau.

         Táº¥t cáº£ nhá»¯ng loáº¡i phÆ°Æ¡ng tiá»‡n truyá»n tin nÃ y Ä‘á»u lá»™ liá»…u, má»i ngÆ°á»i cÃ³ thá»ƒ tháº¥y vÃ 
biáº¿t Ä‘Æ°á»£c sá»± hiá»‡n diá»‡n vÃ  vá»‹ trÃ­ cá»§a Ä‘á»‘i phÆ°Æ¡ng. Do Ä‘Ã³ ngÆ°á»i Ã‚u ChÃ¢u vÃ¬ nhu cáº§u báº£o máº­t
cÃ¡c káº¿ hoáº¡ch hÃ nh quÃ¢n xÃ¢m lÆ°á»£c, cÅ©ng nhÆ° phÃ²ng thá»§, há» Ä‘Ã£ nghÄ© ra cÃ¡ch huáº¥n luyá»‡n vÃ 
dÃ¹ng CHIM Bá»’ CÃ‚U vÃ  CHÃ“ ÄÆ¯A THÆ¯ thay cho cÃ¡c phÆ°Æ¡ng tiá»‡n cá»‘ há»¯u má»i ngÆ°á»i
Ä‘Ã£ quen dÃ¹ng. Cho Ä‘áº¿n giá»¯a Tháº­p niÃªn 1940 qua Ä‘áº§u Tháº­p niÃªn 1950, chÃºng ta tháº¥y quÃ¢n

                                       Ä‘á»™i viá»…n chinh cá»§a PhÃ¡p tÃ¡i xÃ¢m chiáº¿m Viá»‡t Nam váº«n
                                       cÃ²n cÃ³ nhá»¯ng Ä‘Æ¡n vá»‹ Truyá»n Tin Bá»’ CÃ‚U ÄÆ¯A THÆ¯,
                                       lÃ m phÆ°Æ¡ng tiá»‡n phá»¥ dÃ¹ng trong cÃ¡c trÆ°á»ng há»£p nguy
                                       cáº¥p khi cÃ¡c phÆ°Æ¡ng tiá»‡n Ä‘iá»‡n tá»­ VÃ´ tuyáº¿n (radio) vÃ 
                                       Há»¯u tuyáº¿n (wire) vÃ¬ lÃ½ do nÃ o Ä‘Ã³ bá»‹ trá»¥c tráº·c khÃ´ng dÃ¹ng
                                       Ä‘Æ°á»£c.

                                                Tá»« khi QuÃ¢n Äá»™i Quá»‘c Gia Viá»‡t Nam Ä‘Æ°á»£c thÃ nh
                                       láº­p vÃ o Ä‘áº§u Tháº­p niÃªn 1950, trong cÃ¡c Äáº¡i Ä‘á»™i Truyá»n
                                       Tin cÅ©ng cÃ³ trong tá»• chá»©c Trung Ä‘á»™i Bá»’ CÃ‚U ÄÆ¯A
                                       THÆ¯. CÃ¡c Bá»’ CÃ‚U LIÃŠN Láº C VIÃŠN nÃ y Ä‘Æ°á»£c tiáº¿p tá»¥c
                                       nuÃ´i dÆ°á»¡ng vÃ  xá»­ dá»¥ng cho Ä‘áº¿n khoáº£ng nÄƒm 1956 má»›i
                                       giáº£i tÃ¡n, khÃ´ng dÃ¹ng ná»¯a vÃ¬ tá»‘n kÃ©m vÃ  háº§u nhÆ° khÃ´ng
                                       cÃ³ nhu cáº§u.

                                                Theo sá»­ liá»‡u Viá»‡t Nam, thÃ¬ vÃ o Tháº¿ ká»· 15 (trong
                                       khoáº£ng cÃ¡c nÄƒm 1423-1429), thá»i Anh HÃ¹ng Ão váº£i Ä‘áº¥t
                                       Lam SÆ¡n lÃ  LÃª Lá»£i chiÃªu má»™ NghiÃ£ Binh Ä‘Ã¡nh Ä‘uá»•i quÃ¢n

                                                                                                                                                                4</code></pre>
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