[QCWA] Amelia Earhart radio tech data

[Bob Roske]

sri, the listed link doesn't work, thy this one!

http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/signalcatalog.html
  ----- Original Message ----- 
  From: Bob Roske 
  To: QCWA - Reflector 
  Sent: Sunday, September 16, 2012 7:02 AM
  Subject: Fw: Amelia Earhart radio tech data


  Forwarding this post from the Navy Amateur Radio Club http://www.k4nar.org/

  73,
  Bob, N0UF, RM1 (Retired)
  Fair Winds and Following Seas
  ----- Original Message ----- 
  From: BOB CONNER USN RET 
  To: 570 BOB W1NAV 
  Sent: Sunday, September 16, 2012 6:49 AM
  Subject: Amelia Earhart radio tech data


      # 514 Arnal N9ACC sent this to me.  73's, Bob




      NARC,

      Hopefully, non-controversial, except for the Amelia Earhart controversy itself!  This site has a lot of technical information about the radios, frequencies, FRC/FCC/ITU frequency and assignments, harmonics, harmonic output powers, post-loss-reception reports, antennas, receiver specs, etc. involved.  
        http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/signalcatalog.html">http://tighar.org/Projects/Earhart/Archives/Research/ResearchPapers/Brandenburg/signalcatalog.html


      An excerpt:



      "... In October 1930, the FRC[2] re-designated 278 kHz as the “airport frequency” and expanded its mandated use for ground station transmissions to include all aircraft, not just itinerants.

      In December 1931, the FRC[3] revised the national aircraft calling and working frequency from 3106 kHz to 3105 kHz.

      In May 1937, the Federal Communications Commission, successor to the FRC, issued revised regulations[4] allowing all aircraft to use 6210 kHz as a day-only alternate for 3105 kHz. The revised regulations also: defined a ground station transmitting on 278 kHz as an “airport station;” required such stations to maintain a continuous listening watch on 3105 kHz; and restricted the allowed power on 278 kHz, thus limiting communications with aircraft to short distances – about 30 miles.

      Other nations using 6210 kHz[5] (A3) were: Canada, for aircraft use; the Soviet Union for interior communications; and Venezuela, for broadcasting. 3105 kHz also was used by Canadian aircraft flying the route[6] between Vancouver and Seattle."



      Scroll to the bottom of that page and click on any of the other technical pages to see each area.  One of those pages goes into analyzing the non-harmonic-surpressed output of their transmitter and tries to calculate the power output on those (up to 5th) harmonics.

      All for fun, and the technical aspects of this enduring mystery.


      de N9ACC, #514


      Arnal
Robert M. Conner (Bob) W1NAV, #570
ETCS(SS) USN RETIRED 1959-1983
Secretary/Treasurer NARC (K4NAR)
CELL 386-965-8480
PO Box 2192, Lake City, FL 32056 
w1nav at earthlink.net