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.=jka úÿ,s udOH b;sydih m%d¾:kd ùrisxy YS% ,xld mqj;am;a wdh;kh (C)Prarthana Weerasinghe 11/01/2011

Radio history

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Page 1: Radio history

.=jka úÿ,s udOH b;sydih

m%d¾:kd ùrisxyYS% ,xld mqj;am;a wdh;kh

(C)Prarthana Weerasinghe 11/01/2011

Page 2: Radio history

lïìhla Èf.a ixfoaYhla tla ;ekl isg ;j;a ;eklg heúh yelafla flfiao hkak ms<sn\j fidhd .ekSu;a iuÕ .=jka úÿ,s udOHfha b;sydih wdrïN fõ¡

17 jk ishjfia isáhd hehs ms<s.efkk —yshqcskaia˜ (Hugens) keue;s mqoa.,hd tla;rd kHdhla wkqj wdf,dal ;rx. ud,djla wjldYhg fhduq lsÍfuka miq th .=re fldg f.k tla ;ekl isg ;j;a ;eklg ixfoaYhla heúh yels nj fidhd .kakd ,§¡

fulS isoaOdka;h mokï lr .ksñka uhsl,a *erfâ (Michael Faraday) úiska úµq;a pqïNl w;ayod ne,Sï isÿ lf<ah¡

1873 § fcïia la,d¾la uelaiafõ,a (Jemes Clerk Maxwell) th .Ks;uh isoaOdka;hla njg m;a lf<ah¡

(C)Prarthana Weerasinghe 11/01/2011

Page 3: Radio history

(C)Prarthana Weerasinghe 11/01/2011

Page 4: Radio history

1988 oS uelaiafõ,af.a kHdh Wmfhda.S lr .ksñka c¾udkq cd;sl úµd{ fykaßla y¾Üia (Heinrich Hertz) úiska úµq;a pqïNl ;rx. ksIamdokh fldg tajdfha ;rx. wdhduhka uksk ,§¡

(C)Prarthana Weerasinghe 11/01/2011

Page 5: Radio history

y¾Üiaf.a fidhd .ekSïj,g .re lsÍula jYfhka .=jka úÿ,s ;rx. ixLHd;h m%ldY lsÍfï cd;Hka;r m%ñ;sh ±laùu i\yd Tyqf.a ku flá lr Hz f,i Ndú;d lr ;sfí¡

1897 oS ú,shï larEia (William Crooks) keue;a;d m<uq jrg úµq;a pqïNl ;rx. u.ska ix{d heúh yels nj fmkajd foa¡

.=jka úÿ,s hka;%h fidhd .ekSfï f.!rjh ysñ jkafka b;d,s cd;sl .=.a,sfuda ud¾fldaks gh¡

Tyq /yeka rys;j ix{d heúh yels nj fidhd .;a w;r Dot & Dash fyj;a ;s;a iy bß u.ska ikaksfõok lghq;= isÿjk /yeka rys; fg,s .d%*a l%uh b;d,s rchg y\qkajd oqkafka h¡

(C)Prarthana Weerasinghe 11/01/2011

Page 6: Radio history

(C)Prarthana Weerasinghe 11/01/2011

Page 7: Radio history

1897 uehs 20 fjksod ud¾fldaks Wireless Signaling Company kñka iud.ula msysgqù h¡ fuu iud.fï uQ,sl wruqK jQfha ikaksfõok lghq;= i\yd jh¾,ia WmlrK ksmoùuhs¡

1912 § w;a,dka;sla id.rfha .uka .ksñka ;snQ Titanic fk!ldj ihqf¾ mdù wd whsia l=Üáhl yemS .sf,kakg jQ fudfydf;a tys isá u.Skag wdOdr b,a,d isáfha ud¾fldaks ikaksfõok WmlrK Ndú;fhks¡

Titanic isÿùu;a iu. jh¾,ia ikaksfõokh ms<sn| uOH wjOdkh fhduq jkakg úh¡

f,dalfha m<uq f,dal .=jka úÿ,s uOHia:dkh wdrïN jQfha 1920 fkdjeïn¾ 20 fjksod h¡ th KDKA kñka wdrïN úh

bka miq Radio Network ^.=jka úÿ,s cd,d& wdrïN úh

1922 BBC

1935 § Edwin H. Armstrong úiska AM ;rx. fjkqjg FM (Frequency Modulation) fyj;a ixLHd; uQ¾ck y\qkajd foa¡

(C)Prarthana Weerasinghe 11/01/2011

Page 8: Radio history

;rx. moaO;s

moaO;s kduh ixLHd; mrdih

01 b;d my;a ixLHd; Very Low Frequency (VLF)

3KHz – 30 KHz

02 my;a ixLHd;Low Frequency (LF)

30KHz- 300KHz

03 uOHu ixLHd;Medium Frequency (LF)

300KHz -3000KHz

04 WÉp ixLHd;High Frequency (HF)

3MHz-30MHz

05 b;d WÉp ixLHd;Very High Frequency (VHF)

30MHz- 300MHz

06 w;s WÉp ixLHd;Ultra High Frequency (UHF)

300MHz- 3000MHz

07 iqmsß wê WÉp ixLHd;Supper High Frequency (SHF)

3GHz- 30GHz

08 mru WÉp ixLHd;Extremely High Frequency (EHF)

30GHz- 300GHz

(C)Prarthana Weerasinghe 11/01/2011