《the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)》

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the dawn of amateur radio in the u[1].k.(收音机雏形的诞生)- 第26部分


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propagation conditions。 The data for the ionospheric models take up more 

than 200 megabytes of computer storage space。 Operators thus know when 

and     where    to   expect    degraded     performance。       Of    course;    strong   solar 

activity can virtually make over…the…horizon HF radar unusable。 

       A  Spectrum  Analyser   display   shows   all   the   frequencies   between   5 

and   28   MHz。   In   order   to   avoid   possible   interference   to   other   services; 

those frequencies which are known   to be permanently allocated to  fixed 

broadcasting   and   telecommunication   stations   are   locked   out;   as   well   as 

frequencies which happen to be used at any instant so that they can also be 

avoided by the OTHR transmitter。 



       GLOSSARY for non…technical readers。 

     A。M。   A   mode   of   modulation   (amplitude)。   A。R。R。L。   Amateur   Radio 

Relay League (U。S。A。)。 Beacon Transmitter radiating identification signal。 

C。Q。 General call; to any station。 C。R。T。 Cathode ray tube (like TV screen)。 



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               The dawn of amateur radio in the U。K。 and Greece : a personal view 



C。W。   Continuous   wave   (mode   of   sending   telegraphy)。   Callsign   Station 

identification   (letters   &   numbers)。   Coherer   A   device   for   making   radio 

frequencies       audible。    DE    Morse     abbreviation      for  ‘from'    (French)。    DX 

Communication   over   a   long   distance。   Detector   Any   device   for   making 

radio   frequencies   audible。   Doppler   shift   Change   in   pitch   (of   sound)   or 

frequency of a (radio) wave E。D。E。S。 Initials of a war…time Greek guerrilla 

organisation。 E。E。R。 Equivalent Greek initials for R。A。A。G。 (q。v。) E。L。A。S。 

Initials of a war…time Greek guerrilla organisation。 E。L。F。 Extremely Low 

Frequency。   E。M。E。   Earth…moon…earth。   Also   Moonbounce   q。v。   H。H。M。S。 

His Hellenic Majesty's Ship。 Gasfet A type of transistor。 KHz Kilohertz … 

international unit for kilocycle。 M。U。F。 Maximum usable frequency。 MHz 

Megahertz          …    international       unit      for    megacycle。         Moonbounce 

Communication   by   reflection   from   the   moon。   OTHR   Over…the…horizon 

radar。 Q code Abbreviations used when communicating by telegraphy。 Q1 

Unreadable。   Q2   Barely   readable   …   only   some   words。   Q3   Readable   with 

considerable   difficulty。   Q4       Readable   with   practically   no   difficulty。   Q5 

Perfectly     readable。     QRO      High    power。    QRP     Low     power。     QRT     〃Stop 

sending〃。 Frequently used for 〃shut up〃。 QSO Two…way communication。 

QST      Call   to  all  stations。   Also    title  of  journal    of  the   A。R。R。L。     QTH 

Location or address of a station。 R。A。A。G。 Radio Amateur Association of 

Greece。   R。F。   Radio   frequency。   R。S。G。B。   Radio   Society   of   Great   Britain。 

RST   System   of   reporting   readability;   strength   &   tone   of   a   signal。   RX 

Receiver。   S   unit   Unit   for   reporting   strength   of   received   signal。   S。I。   unit 

International   system   of   definitions。   SSB   Single   side…band   …   a   mode   of 

modulation。   SWL  Room   where   radio   equipment   is   set   up。   Shack   Room 

where     radio    equipment      is  set  up。  Silent    key   Deceased      radio   amateur。 

Sporadic       E。   Propagation      via   the   E   layer    of   the   ionosphere。      T。E。P。 

Transequatorial propagation。 TX Transmitter。 Troposcatter Propagation via 

the troposphere。 U。H。F。 Ultra high frequency。 V。H。F。 Very high frequency。 

W。A。C。 Worked (contacted) all continents。 XYL Wife of a radio amateur。 

YL Young lady operator。 73 Morse abbreviation for ‘‘best regards''。 Yagi A 

type of antenna designed by a Japanese of that name。 



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