West Coast Groundfish Observer Program Manual, Part2 - NOAA

APPENDIX R
Channels 7. 8. 9. 10. 11. 18. 19. 67. 68. 69. 70. 71. 72. 78. 79. 80 and 88 are commercial and noncommercial
working channels that are available for conducting business. The abbreviated format (no
call signs) is acceptable on these frequencies. It should be noted that some of these channels may be
locally restricted (off the Washington Coast, for example, channel 11 is Tofino Coast Guard Traffic
Control for the entry into Juan deFuca Strait, used for reporting ship locations), in which case their
use for business should be avoided.
HF-SSB Radios
To communicate over distances of beyond twenty miles, you will need to use satellite
communication or a medium to high frequency radiotelephone referred to as Single Side Band (SSB)
radio. The signal is poorer in quality than VHF and susceptible to slight atmospheric shifts. Lower
frequencies are used for medium distances and higher frequencies for greater distances. The general
rule for single sideband frequency selection is: multiply the frequency in MHz by 100 to obtain the
approximate coverage distance in miles. At night however, the ranges of SSB radio wave travel are
from 2-3 times greater. Therefore, use a lower frequency at night to cover the same distance.
All ship SSB radiotelephones must be capable of operating on 2182 kHz, the international distress
and calling frequency, and at least 2 other frequencies. Numerous channels are available for your
use; which ones are available varies from place to place. However, channel 2670 kHz is only used for
communicating with the Coast Guard and should not be used for other purposes.
When using SSB radiotelephone, you must observe radio silence on channel 2182 kHz, the
emergency channel, for 3 minutes immediately after the hour and the half hour. The purpose of
radio silence on the emergency hailing channel is to clear the airwave for weak or distant distress
signals. No radio silence is used on the VHF emergency channel: channel 16.
Radio Procedure
In as much as the airwaves are in the public domain, it is the responsibility of the radio station
operator to conduct business according to established guidelines and procedures. While on the air,
the operator should follow the following format outline:
1) Listen before beginning transmission in order to ensure that you are not interfering with
other stations or with emergency radio traffic.
2) Identify your station when calling. On the SSB, a calling station must limit the duration of
the hail to not more than 30 seconds. If there is no reply, the hail may be repeated at 2
minute intervals up to a maximum of three times, at which time the calling station must sign
off and wait a minimum of 15 minutes before making another attempt. This requirement
does not apply in emergency situations.
3) Keep transmissions short and concise, giving the other station a chance to respond, ask
questions, or reconfirm an unclear message. A long, complicated message can best be
effected in short segments with breaks in between to ensure that the receiving station has
copied each portion of the message correctly.
4) Follow correct radio procedure while on the air. The phonetic alphabet should be learned
and used spelling unclear words with an extemporaneous phonetic alphabet can lead to
misunderstood messages. You should also know and use the radio “punctuation” words
(“over”, clear”, “out”, “roger”, “words twice”, “say again”, “standing by”, and “break”).
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1/30/2004