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  • Long Pac 2013



    The 2013 400 nm Single Handed Transpac qualifier is underway, and most of the boats had a hell of a time getting though the 1st 100 nm due to strong NW winds. California Condor is nearly finished with this exercise while most of 20 boats which started Wednesday are nearing the 1/2 way mark.




    Brian Boschma has been working with VHF and keeping contact with the communications
    boats from a perch with a clean line of sight, 2,600 feet up on Skyline Ridge near Castle Rock State Park. Part of this exercise is for fun, part is to establish a usable communications alternative to expensive satellite phone or SSB for near coastal offshore
    events...Brian reports good reception to boats over 150 nm away! More later!






    http://sfbaysss.org/longpac_2013.html
    Last edited by Photoboy; 06-21-2013, 11:29 AM.
    " I just found out my nest egg has salmonella"



    h2oshots.com Photo Gallery

  • #2
    Um... the Long Pac is NOT the qualifier for the Pac Cup.
    life is a reach_/) _/)

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    • #3


      A video of last nights radio communication, courtesy Nuttball ...
      " I just found out my nest egg has salmonella"



      h2oshots.com Photo Gallery

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      • #4
        Originally posted by Phil MacFarlane View Post
        Um... the Long Pac is NOT the qualifier for the Pac Cup.
        Sorry, brain bone not connected to keyboard bone quite yet...

        SH Transpac...
        " I just found out my nest egg has salmonella"



        h2oshots.com Photo Gallery

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        • #5
          Nice to see some familiar names out there, again...

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          • #6


            The view looking west from RedSky communications secret location high atop Highway 35










            To reach vast distances via vhf, you need the right gear, in this case a ®edsky Communications
            custom antennae...

            Brian shall fill you in on the minute details in a bit...
            " I just found out my nest egg has salmonella"



            h2oshots.com Photo Gallery

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            • #7
              I wondered how he would make that work! I pictured swallowing a potion that would result in a 900 foot tall Brian astride Mt. Sutro, glowing chartreuse.

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              • #8
                Actually you just pull the plumbing and electrical wiring out of one room to make that Yagi

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                • #9
                  But that's not Coppertop . . .

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                  • #10
                    Sad to say it was not Some day we need to do another race like that... Now all I need to do is talk Sly / Syn to do it again

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                    • #11
                      Red Sky Communications For Offshore Contact



                      Brian Boschma is always thinking. Earlier this season he developed a simplified course tracking app for Android phones Click for thread and also shed light on a bizarre anomaly with the new easter span of the Bay Bridge which causes auto pilots to deviate wildly when passing under said structure ( a major hazard for short handed sailors)* (see bottom of post)

                      Brian's latest contribution is a venture into simplifying and making affordable communication with sailors engaged in nearby offshore events. Using a home built high gain antenna and finding a clear line of site location, Brian was able to communicate with vessels nearly 200 miles offshore! Check out his results from this past weeks SSS Long Pac communications test!


                      With the need for enhanced communication requirements for offshore racing I decided to experiment with what might be feasible, with regards to range, using VHF. The SSS Long Pac presented a good opportunity to experiment with range as the boats go offshore 200 miles before turning home. Winds usually force some south-ing and turn around points as far south as Santa Cruz are not uncommon. In this years event boats came down to 36:13N, in line with Monterrey (S/V Galaxsea). A high gain antenna was constructed to use atop several possible sites up to 3000 feet. The mountains north of Santa Cruz are perfectly placed for coverage along the coast from 38N to 36N latitude. The fleet had scheduled check ins at 0900 and 2100 each day, which were optional as they also were checking in on SSB a half hour later. Most were also posting positions by one of several satellite services.

                      The following is a summary of coverage achieved at sites between Castle Rock State Park and the Windy Hill Ridge at altitudes from 1800 ft to 3000 ft. One test was conducted from the peak of the boulder field at Castle Rock, so the gear was compact and hand carried in several instances.

                      Jun 19: The bulk of the fleet was in the vicinity of the Farallone's at the 2100 check in. I easily communicated with 6 boats that were present on channel 72. Tiger Beetle was a good example. She reported an excellent signal and we carried on a short conversation with her on 1 watt and my station on 5 watts. I was operating at 2600 feet altitude west of Palo Alto.

                      Jun 20 AM: Again several boats were contacted and were reporting positions beyond 124 Long. Signals were quite strong and my signal was reported as excellent. I was at 3000' located west of Los Gatos.

                      Jun 20 PM: Boats were reporting positions beyond 125 W Long. I spoke with Coyote and Carrol E. as they did the VHF check in. Carrol E, a Dana 24, was about 150 miles distant. Both boats had solid signals. I heard any vessel they heard and did a bit of relaying between the two comm vessels.

                      Jun 21 AM: I spoke to Humdinger and Rainbow. Humdinger had made the turning Longitude and was headed home, position 124.02 W. Rainbow, at 125.67W, had about 70 miles to go to the turning point. She was about 170 miles away from my position.

                      Impressions: There is merit in providing a communication platform on the Santa Cruz range to cover vessels from SF to Monterrey and out to at least 150 miles. Beyond 150 miles my experience shows that conditions may be a bit spotty as you are depending on atmospheric refraction. During this event however, I was getting excellent reports to about 170 miles out. Coverage of the Gulf of the Farallone's and points South to Point Sur would be relatively easy with appropriately positioned radios and high gain antenna.










                      *
                      The new Bay Bridge stanchions, on the NE side of the bridge exhibit a substantial magnetic anomaly. In two recent passes through the bridge I have measured shifts of over 30 degrees when passing under the bridge and within a few boat lengths, approximately 80 feet, of the stanchions. The anomaly is most pronounced near the center of the road bed above you. If you are steering by autopilot this anomaly can lead to a collision with the piers. I happened to be testing an AP on Apr 11 and opted to engage to see the effect. As you approached the piers from the north the AP would attempt to alter the course significantly towards the east. Traveling from south to north and with the piers within a few boat lengths would have certainly resulted in a collision. My measurements were to the east of the E pier, this is outside the new construction zone (the area with scaffolding, between E and Yerba Buena, is restricted). I then made another pass paying close attention to a flux gate compass with heavy damping, while moving at about 3 kts. The shift was apparent in the readings. The old piers, to the south, showed no such disturbance. I pass this along as a safety tip. I already know of one boat that mysteriously hit the new construction when an AP made an unplanned abrupt turn.
                      " I just found out my nest egg has salmonella"



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                      • #12
                        Great job Brian! BAMA and others in NCORC have been working on a similar concept and with the additional feature of it being controlled. Great news!

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                        • #13
                          Brilliant solution Brian!!!

                          Is it feasible to place high gain antennas as repeaters so signal could be received at race decks,
                          or would utilizing this concept require volunteers to deploy to various locations to keep contact?

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                          • #14
                            Impressive. What sort of investment would it take to get an antenna setup like that to cover the gulf of the Farallones during a race?

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                            • #15
                              Gulf of the Farallones, Cost ?

                              Covering the Gulf of the Farallones is pretty trivial. From the top of lands end you should be able to cover the distance to the islands with a standard 6 db co-linear, easily purchased through WM. You would have a small hole in the direct shadow of the island. Using a Yagi would direct the signal to the islands and probably more important reduce signals from the bay, helping with interference reduction.

                              The little antenna I made was inexpensive on the materials end, about $15. A commercial version could be had for about $120. For reliable longer range other solutions exist.

                              A repeater would be possible but you would have to move the up-link/down-link to non Marine VHF frequencies. Likely a simpler approach would be to use a cell phone as the up link/down link. One would dial the cell phone and use key sequences to transmit/receive and possibly change frequency. FCC regulations would need to be checked as to what the requirements are.

                              I have heard rumors of attempting to establish a permanent site. Seems expensive what with site rental, tower space, and assuring non interference with existing users.

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