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  1. #1
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    Lowrance Point 1 Antenna

    I have received a lot of questions recently concerning the new Point 1 antenna. The main difference between these and a LGC 4000 is their built in 10 Hz heading sensor which provides chart stabilization and radar overlay, plus accurate course over ground indication even at low speeds. Lowrance did not invent the heading sensor with this device, but they are offering an economical alternative. The Point 1 mounts directionally to keep track of the bow orientation.

    What will be different on the water? With a LGC4000 or the HDS internal antenna and a "Heading Up" chart selection, when you begin reversing the chart will spin. As you back up with a Point 1 antenna the chart orientation will not change because the bow of your boat is still pointing in the original direction. Locating waypoints is easier, but I would still throw a buoy.

    Point 1's work with the same units as LGC 4000's. The HDS Gen2's and Touch units operating with the new Version 2.0 software have the ability to initiate a calibration sequence from the Device List-Details. On Gen 1's or older 520's, etc., calibrate the antenna by unplugging it from the NMEA backbone then plug it back in. Immediately following this begin turning you boat in a slow circle (2-3 minute). The completion of one circle initiates the calibration process, and a second should complete it.

    HDS Gen2 and Touch units running Version 2.0 software also have GPS damping and filtering features that will not be present in HDS Gen1 or older units, but the antennas will work fine.

    You cannot run two Point 1 antennas on a single NMEA network because they do not contain a hard-coded identifier for the heading sensor, like the more advanced electronic compasses do. If another heading sensor appears on the NMEA backbone they disable themselves to avoid conflicting data. I recently installed 2 on one boat, but it required a separate NMEA backbone to a dedicated charting unit on the console. The forward mounted Point 1 was included in the main NMEA backbone with 4 other locators. The customer absolutely wanted 2 of them.

    Point 1 antennas contain a very sensitive electronic compass in the housing. Therefore it is very important to mount the antenna away from anything that emits a magnetic field like trolling motors, VHF antennas, radars, even outboard wire looms. Lowrance recommends 20" of separation but my experience indicates that may not be enough. I debugged a pro tournament boat 2 weeks ago where the chart page looked like Martians had taken over...everything was spinning randomly. The antenna was mounted right on the nose of the boat and the magnetic force of the trolling motor hijacked the gyro. It took 3' of separation to obtain proper operation. Nothing like an extra 3/4" hole in the boat from the original mounting location.

    The internal HDS GPS antennas are fine for positional accuracy and can be selected over the GPS portion of the Point 1 antenna in Data Sources. The heading sensor in the Point 1 provides chart stability. It selects individually under Vessels, so you can run any antenna in the boat on the NMEA network, even a LGC 4000 on the bow, in combination with the Point 1 heading sensor. If you want advanced directional stability like auto pilots often require, look into a Maretron SSC200.

    The SSC200 is a 3-axis magnetometer, a 2-axis accelerometer and a rate gyro. The outputs of all these sensors combine in a software algorithm running on an internal microcontroller to give high precision and extremely stable heading information. Without a Maretron display, the calibration is a bit cumbersome, but it can be controlled from a PC using a terminal emulator. Many of the barge company work boats on the Mississippi contain these devices in combination with their radar.
    Last edited by Talon; 05-16-2013 at 07:30 AM.

  2. #2
    Very informative Talon, thank you very much for sharing this information.

  3. #3
    Talon,

    Do you recommend running both a LGC 4000 antenne and a Point 1 antenne in a boat?
    Does it have advantages over using the internal antenne + Point 1.

  4. #4
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    Danny I run a point -1 on my TM and LCG 4000 on my console with separate nema's but do have my units ethernet. I basically fish crappie rarely throw bouy. I really like the Point -1 over the 4000
    I have an issue with unit the Point-1 refreshing which I am sure Lowrance will fix. Just found out lowrance is coming out soon with a fix for the staionary extension line.
    That is great news. Gary
    Last edited by Stillbear; 05-20-2013 at 05:20 PM.
    Gary
    Ranger Comanche 1983 370-V
    Yamaha 150
    Minn Kota 80 LB Maxxum 24 V Lift Assist
    2-HDS 10 Gen 2 Bow & Console
    1-LGC 4000 Console
    1-Point 1 Bow

  5. #5
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    Danny,

    The performance of the LGC 4000 and the internal antennas just keep converging. Honestly with the updates afforded by Ver. 2.0 software I am not seeing much practical difference between the functionality of the two. Historically LGC 4000's have yielded better results on lakes with steep adjacent terrain. I have not tested that with the new software update, but on open lakes the internal antennas are now pretty comparable. Even the EPE and SNR values indicate this.

    The biggest Point 1 issue is the software problem Gary alluded to above. The dilemma does not come into play if you continue to move .8 mph or faster, but it becomes very frustrating while trying to remain stationary or drifting slowly with the wind.

    After hovering in one location for a bit, the chart develops a 30-40 second positional update lag. If you enable a heading overlay and turn in a circle you see the heading overlay keeping up with your true position, but the heading extension on the chart will be stationary for 30-40 seconds, then “jump” to the correct heading and position. Keep turning and it jumps again in 30-40 seconds.

    To correct the issue:
    Under Settings-Network-Data Souces-Vessel – Set Heading, Turn, Roll, Pitch to Local and select the Point 1
    Under GPS Source – Set Scope to Local and select any antenna (internal, LGC 400) other than the Point 1

    This disables the antenna portion of the Point 1, but maintains the heading sensor function. Now the antenna will work at all speeds.

    With these settings, there is no reason to run more than one Point 1 in a boat. All you need is one heading sensor, and then pick separate antenna locations for each locator if you want.
    Last edited by Talon; 05-21-2013 at 11:07 AM.

  6. #6
    Coming in late on this. I have read forum after forum and you seem to have the best advise. I have a 20' pathfinder and as you know you can only get so much separation of electronics on the center console. You started the lowrance wants 20" separation from a vhf radio antenna and their installation guide shows 6 feet. That 6 foot is real had to do. I have an HDS 8 gen 1, just updated it after seeing that the refresh time was real slow, I also have the sonic hub hooked in. I really want to add the point 1 instead of the lgc 4000. Looks like my separation would be about 30". The other question is what if I add the sirus weather receiver, is that antenna going to create problems being 18" from the point 1? Your suggestions will greatly help me. Thanks.

  7. #7
    Senior Member
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    For finding seperation distance for any electronics. I test it with a weighted moveable flexible board , bracket, or clamp. Move the object to a workable position . Now you can mount the unit or whatever permanetly . Gary
    Gary
    Ranger Comanche 1983 370-V
    Yamaha 150
    Minn Kota 80 LB Maxxum 24 V Lift Assist
    2-HDS 10 Gen 2 Bow & Console
    1-LGC 4000 Console
    1-Point 1 Bow

  8. #8
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    After working with a dozen or more Point 1 installs, the greatest interference always comes from the trolling motors, especially the 36V models, and radar. You should be fine with 30" of separation from a VHF antenna. I have a Sirius Weather receiver but I have not located the Point 1 antenna next to it. Will investigate that but I suspect minimal effect.

    Gary's suggestion is a good one. My approach to Point 1 installs has been a little more redneck. I tape them into place with duct tape then check for interference and proper operation via the HDS before drilling holes for permanently placement.

    The Lowrance software patch should be released soon correcting the earlier Point 1 glitch. These antennas work well.


 

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