I saved this e-mail from an SWL list of which I am a subscriber. Click on
the link just below to see some very detailed info on these beacons found
wondering in the 160 meter band. Click on Radio Bouy when you get to the
site. Interesting!
http://www.taiyomusen.co.jp/ehomepage/eindex.html
Rick
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Subject: [WUN] More of HF bouys for fishermen-Fascinating
>to Group:
>Since I've become interested in HF direction finding, I've become aware of
>the network of HF bouys used by high seas fishermen to mark the ends of
their
>nets or long lines.
>A friend has provided more fascinating background, which i'd like to share.
>
>>From EMails (pasted together)
>
>" I went to COMFISH EXPO in Seattle last year. The Japanese company (I
have
>their brochures somewhere) that makes the line marker buoys was showing
their
>latest models, including GPS position reporting (which is going to make the
>DFs less necessary and slowly less valuable) and TRANSPONDING buoys that
only
>respond to a digitally coded HF inquiry, and then either activate their
>beacon (usually around 1.6-2 MHz) and/or report GPS position. Transponding
>mode saves on battery drain. Taiyo was not showing at the show
unfortunately.
>
>The purse seine tuna boats dont use the buoys for nets, since they always
are
>attached to their seines, but they use them to mare FADs, floating
aggregator
>devices, a fancy word for what used to literally be logs. Tuna, especially
>Yellowfin, often congregate under any large floating object. Boats used to
>drop off logs and then come back (often days) later and seine a circle
around
>the log. Some "logs" got pretty spohiStcATED DURING THE HEIGHT OF THE
>yELLOWFIN FISHERY (BEFORE THE dOLPHIN RULES WERE ADOPTED). Some had active
>echo sounding gear which would send off an HF signal if repeated strong
>echoes were detected indicating that a school had congregated under the
log.
>
>Also, buoys ARE used to mark drift nets... those multi mile long gill nets,
>mostly illegal now. When I fished tuna commercially in the mid Pacific we
>used to constantly tune for buoys when running at night. If you heard ANY,
>then you knew you were in a drift net infested area and had to proceed with
>caution. Many of the drift nets were not marked with any beacons, just end
>buoys, often barely or non radar reflective.
>
>If you cross one of these nets and foul it in your prop, it can turn into a
>nightmare tangle of monofilament, some melted by the friction as your
engine
>fights a losing battle to keep the shaft turning amidst the growing mass of
>net (the prop acts like a reel and winds in more as it turns). Some boats
>have been immobilized for days as crewmen make repeated dives with hookah
>hoses and saws away at the mess.
>
>The buoys all seemed to be above the broadcast band and below 2 MHz, with a
>very few in the lower 2 MHz region. Most (in the mid 70s) were just
>repeating Morse CW, about 1 watt from what I have seen in the ads by the
>mfrs. Now they are more sophisticated. The USCG flies HC 130 fisheries
>patrols out of Adak AK looking for illegal high seas drift nets. They used
>to nail a few of these pirates by simply using their standard aircraft nav
>ADF and searching for beacons. That may be one of the reasons (besides
>battery life) why the transponder buoys have found a market. The penalties
>for illegal drift net fishing are severe, seizure and sales of boats is the
>norm. Most of the pirates these days are mainland China boats, with fake
>registrations and names. They often repaint and reconfigure (using plywood)
>above deck structures to make tracking and ID difficult. Crews are often
semi
>slaves "recruited" from poor islands around Indonesia. The boats are very
>lucrative if not caught. The rumor is that they are owned by a group of
high
>ranking military officers in China.
>
>---
>The Worldwide UTE News (WUN) mailing list. WUN is a non-profit,
>dues-free club established in 1995 to share information on shortwave
>utilities. For more information: http://www.wunclub.com/
>
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