Radio navigation beacons in Lebanon

Non-directional radio navigation beacons at known locations provide navigatonal aid to marine and aeronautical traffic. Navigation is performed using direction finding radio receivers with antennas which, when turned to a direction where the beacon's signal is weakest, will indicate the direction to (or from) the beacon's position.

The beacon at the AUB beach in Beirut transmits the 3-letter signal BOD in morse and is colocated with the outer marker on the ILS approach to Runway 17 at Beirut airport. BOD is also used for marine navigation.

BAB is at Ouzaai, colocated with the inner marker on the ILS approach to RWY 17.

SD is located at the former Zahrani terminal of Tapline (Trans Arabian Pipeline Company) and was erected in 1950. It is used primarily for marine navigation.

Links for sound, positions with frequencies:

  
 BOD: N33.903° E35.482° 351Khz

  
 BAB: N33.848° E35.486° 312Khz

  
 SD:  N33.502° E35.343° 296.5Khz

John J. Makkinje, Tapline's former Superintendent of Communications writes on 20110131:

Tapline's beacon had a tube type audio oscillator and the keying was
done mechanically.

A small electric motor driving a gear box with two output shafts.
One shaft turned at a lower speed than the other and on each shaft was
a disc that had sections removed from the outer edge allowing a
microswitch to key the signal.

The disc for S D in Morse Code was cut with the following pattern:

    --------_-----_-----_-------___-----_-----_---------

Three revolutions of the disc would key "SD" three times. The other
disc was cut to give a continuous tone for the next twenty seconds
or so, then it would open and the SD wheel then keyed the code again.
Sometimes the tone would become a bit jittery because the microswitch
contacts became dirty, affecting the tone output. 

Note: BOD and BAB were recorded with the help of Riri Azrak (OD5RI) in Jan. 2011 and SD was recorded in Dec. 1997 by Børre Ludvigsen.

al@mashriq

Last modified: Wed Feb 25 13:03:26 2015