§  87.149   Special requirements for automatic link establishment (ALE).

   Brief signalling for the purposes of measuring the quality of a radio
   channel and thereafter establishing communication shall be permitted
   within the 2 MHz-30 MHz band. Public coast stations licensed under part
   80 of this chapter providing high seas service are authorized by rule
   to use such signalling under the following conditions:

   (a) The transmitter power shall not exceed 100 W ERP;

   (b) Transmissions must sweep linearly in frequency at a rate of at
   least 60 kHz per second, occupying any 3 kHz bandwidth for less than 50
   milliseconds;

   (c) The transmitter shall scan the band no more than four times per
   hour;

   (d) Transmissions within 6 kHz of the following protected frequencies
   and frequency bands must not exceed 10 uW peak ERP:

   (1) Protected frequencies (kHz)
   2091.0 4188.0 6312.0  12290.0 16420.0
   2174.5 4207.5 8257.0  12392.0 16522.0
   2182.0 5000.0 8291.0  12520.0 16695.0
   2187.5 5167.5 8357.5  12563.0 16750.0
   2500.0 5680.0 8364.0  12577.0 16804.5
   3023.0 6215.0 8375.0  15000.0 20000.0
   4000.0 6268.0 8414.5  16000.0 25000.0
   4177.5 6282.0 10000.0

   (2) Protected bands (kHz)

   4125.0-4128.0

   8376.25-8386.75

   13360.0-13410.0

   25500.0-25670.0

   (e) The instantaneous signal, which refers to the peak power that would
   be measured with the frequency sweep stopped, along with spurious
   emissions generated from the sweeping signal, must be attenuated below
   the peak carrier power (in watts) as follows:

   (1) On any frequency more than 5 Hz from the instantaneous carrier
   frequency, at least 3 dB;

   (2) On any frequency more than 250 Hz from the instantaneous carrier
   frequency, at least 40 dB; and

   (3) On any frequency more than 7.5 kHz from the instantaneous carrier
   frequency, at least 43 + 10log10 (peak power in watts) db.

   [ 62 FR 40308 , July 28, 1997]

   return arrow Back to Top