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Re: Replacing Older OT1m System

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  • MarcGorelnik
    Scott, Thanks for the helpful response. I ll have to pull the units from the boat and do some bench testing. Something has gone amiss. Marc
    Message 1 of 13 , Jan 15, 2013
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      Scott,

      Thanks for the helpful response. I'll have to pull the units from the boat and do some bench testing. Something has gone amiss.

      Marc

      --- In tracker2@yahoogroups.com, Scott Miller wrote:
      >
      > Hi,
      >
      > > The current system consists of:
      > > 1. OT1m
      > > 2. VX150 2m radio (power switched by OT1m)
      > > 3. GPS receiver (always powered)
      > > 4. Comet B-10 antenna
      > >
      > > The system has always drawn too much power. (I.e., 4d battery drops
      > > below 12.0 VDC after 1-2 months, which is much faster than
      >
      > Have you put an ammeter on it to check what it's drawing? The GPS
      > receiver will probably draw around 50 mA, and an OT1m maybe around 12 mA.
      >
      > For current models, you can expect about 20 mA for the OTUSB and around
      > 70 mA for the OT3m, though that should drop with future firmware updates.
      >
      > > 1. Tracker with low stand-by current.
      > > 2. Ability to power-down the radio and GPS until needed.
      > > 3. 5W or more.
      > > 4. Ability to plug-in laptop to send and receive Winlink email. (lowest
      > > priority)
      >
      > The T3 has higher standby current, but it's also going to be your best
      > bet for Winlink. I've been doing a lot of work in the last week to get
      > connected mode applications working smoothly using KISS. Some of that
      > will carry over to the OTUSB. A few tweaks will also go to the T2 but
      > it doesn't have the extra RAM the newer units do.
      >
      > No GPS power-down yet, but as time allows I'll be experimenting with
      > low-power modes on various GPS receivers.
      >
      > Scott
      >
    • Matthew Cook
      I d suggest that Marcs biggest consumer of power will be the GPS 50-70mA. However switching the GPS and radio on and off together won t work since the GPS
      Message 2 of 13 , Jan 15, 2013
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        I'd suggest that Marcs biggest consumer of power will be the GPS 50-70mA.  However switching the GPS and radio on and off together won't work since the GPS requires time to lock and is variable from 3s to 30 minutes.

        Low power modes in GPS modules is a hit and miss afair, every one does it differently and not everyone is telling the truth in their datasheets either.

        I've tested litterally tested tens of different GPS chipsets for our HAB experiments and have finally settled on the Atmel ublox MAXQ series.  These at least seem to do what you tell them and when.  To get the lowest power consumption you have to drop the majority of GPS units out of NMEA mode and switch to binary.  That way you can hot start (aka poll) the GPS module when *you* want a position report, wait 1s for the next response and then transmit.  So far I've got the current consumption of the Atmel ublox module down to 12mA (hot start) with a passive chip antenna.  It hot starts in under 1s, peaks at 50mA for 3s every time I poll the unit (negligible).  However aquisition draws 72mA until lock/position is attained and then drops to hot start.

        I've also been working on a APRS tracker for my boat, which does pretty much the same thing as what Marc is doing.  I'm more interested in knowing its still where I left it, that the bilge is empty and that the batteries are in good condition (telemetry).  I now live 25mi from the marina, so it's a long round trip every fortnight to go and check.

        Scott if you were to look at low power modes then it would be worth switching to the binary protocol and looking for a GPS module with hot start capabilities.   I think it wouldn 't be too hard to then put in a script that allowed us to switch profiles when the boat starts to move, which then switches from a 30min update rate to a smart beaconing routine taylored for yachts/power boats. It's then just a simple matter of switching the HT at the appropriate time. It would also be nice if we could somehow get the PARAM information into the TNC so that APRS.fi can give us pretty graphs of battery volts etc.   I'd certainly be willing to buy/build/test such a unit.  I've got two boats to test it on (yes I'm greedy and likes my boating/fishing), and a mate of mine has a shiny new sports car that sits in his garage that wants one also.   Definitely food for thought.

        73's

        Matthew
        VK5ZM

        On 15 January 2013 06:55, Scott Miller <scott@...> wrote:
         

        Hi,



        > The current system consists of:
        > 1. OT1m
        > 2. VX150 2m radio (power switched by OT1m)
        > 3. GPS receiver (always powered)
        > 4. Comet B-10 antenna
        >
        > The system has always drawn too much power. (I.e., 4d battery drops
        > below 12.0 VDC after 1-2 months, which is much faster than

        Have you put an ammeter on it to check what it's drawing? The GPS
        receiver will probably draw around 50 mA, and an OT1m maybe around 12 mA.

        For current models, you can expect about 20 mA for the OTUSB and around
        70 mA for the OT3m, though that should drop with future firmware updates.


        > 1. Tracker with low stand-by current.
        > 2. Ability to power-down the radio and GPS until needed.
        > 3. 5W or more.
        > 4. Ability to plug-in laptop to send and receive Winlink email. (lowest
        > priority)

        The T3 has higher standby current, but it's also going to be your best
        bet for Winlink. I've been doing a lot of work in the last week to get
        connected mode applications working smoothly using KISS. Some of that
        will carry over to the OTUSB. A few tweaks will also go to the T2 but
        it doesn't have the extra RAM the newer units do.

        No GPS power-down yet, but as time allows I'll be experimenting with
        low-power modes on various GPS receivers.

        Scott




        --
        Matthew
        VK5ZM
        0487 653 245
      • Scott Miller
        ... I ll probably start with the GT320FW. I ve got specs on the Prolific binary format around here somewhere. I m mostly not sure how good the first fix or
        Message 3 of 13 , Jan 15, 2013
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          > Scott if you were to look at low power modes then it would be worth
          > switching to the binary protocol and looking for a GPS module with hot
          > start capabilities. I think it wouldn 't be too hard to then put in a

          I'll probably start with the GT320FW. I've got specs on the Prolific
          binary format around here somewhere. I'm mostly not sure how good the
          first fix or two will be.

          > could somehow get the PARAM information into the TNC so that APRS.fi can
          > give us pretty graphs of battery volts etc. I'd certainly be willing
          > to buy/build/test such a unit. I've got two boats to test it on (yes

          Do you mean from an NMEA stream? Send me samples and I'll see what can
          be done.

          Don't be surprised if I'm not very responsive this week, though. Parts
          are due in tomorrow morning and we'll be going flat out for a day or two
          trying to get caught up.

          Scott
        • James Ewen
          ... We already have the scripting capability, profile switching based on speed, and fixed rate/SmartBeaconing. Using the binary protocol however would mean
          Message 4 of 13 , Jan 15, 2013
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            On Tue, Jan 15, 2013 at 8:42 PM, Matthew Cook <vk5zm@...> wrote:

            > Scott if you were to look at low power modes then it would be worth
            > switching to the binary protocol and looking for a GPS module with hot start
            > capabilities. I think it wouldn 't be too hard to then put in a script
            > that allowed us to switch profiles when the boat starts to move, which then
            > switches from a 30min update rate to a smart beaconing routine taylored for
            > yachts/power boats.

            We already have the scripting capability, profile switching based on
            speed, and fixed rate/SmartBeaconing. Using the binary protocol
            however would mean that you would be limited one one specific GPS, or
            series of GPS as each one will have a proprietary communications
            protocol. NMEA is a common language.

            > It's then just a simple matter of switching the HT at
            > the appropriate time. It would also be nice if we could somehow get the
            > PARAM information into the TNC so that APRS.fi can give us pretty graphs of
            > battery volts etc.

            You can do that with scripting right now. Not many places display the
            telemetry parameters. If you are only wanting to get the parameters
            into aprs.fi, you can simply send the parameters once, and they will
            "stick" for a very long time.

            > I'd certainly be willing to buy/build/test such a unit.
            > I've got two boats to test it on (yes I'm greedy and likes my
            > boating/fishing), and a mate of mine has a shiny new sports car that sits in
            > his garage that wants one also. Definitely food for thought.

            Pony up the pennies... you've got 95% of what you are asking for
            sitting on the shelf!

            The OT+ will do everything you want except talk in a proprietary
            binary mode to the GPS of your choice, and poll it for a position.

            --
            James
            VE6SRV
          • Matthew Cook
            I ve already stumped the pennies into a T2 + Alinco HT for my yacht at least. The scripts were easily written, mind you took me a while to debug. To solve
            Message 5 of 13 , Jan 16, 2013
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              I've already stumped the pennies into a T2 + Alinco HT for my yacht at least.  The scripts were easily written, mind you took me a while to debug.

              To solve this GPS Power/APRS tracker problem I've been working on a MSP430 that sits between the T2 and the GPS.  The MSP430 puts the GPS (ublox) into binary low power mode (hot start) and implements a variable GPS polling period (based upon speed) and then simply tells lies to the T2 every second by sending fake NMEA sentances.  The MSP430 currently adds 2mA to my overall consumption.  I've down to 25-27mA depending on how to look at the AVO.

              The MSP430 sits there and polls the GPS and watches the speed.  If the speed starts to change then the GPS polling period is varied, this should sound familiar?  Yes I've simply copied the SmartBeaconing(TM) algorithm again.

              Anyway if we could get a T3 that can read any one of the GPS units in a low power (and if necessary binary) mode and poll the GPS for a position before transmit then I'd certainly be looking for such a unit.  Programming my MSP430 is a PITA, since I've got to copy the SmartBeaconing parameters out of the T2 and feed them into my software.  It works but it's certainly not production ready, nor do I wish to release/develop this further.  Was just trying to solve the same problem as Marc.

              I hope that the ideas above gives Scott some thoughts as to how this low power GPS mode could be useful.

              I've found the hot start mechanism in the Atmel ublox is pretty good, meaning the positions when polled are coming out as expected.  The prolific chipsets I had no end of trouble with in general.  They were not as well supported as the ublox in terms of others having used them.

              With regard to the GPS, having a unit that can mount on the deck of the boat and sends serial back (hockey puck style) would be preferable to say a GPS module within the T3.  An internal module would require an external antenna with active preamp to get around the cable loss and NF issues, which adds 10-12mA to the overall current consumption; this will blow your power budget.

              The HT and T2 I've hidden under the deck using the HT rubber duck.  I've found that this gets into the local APRS system well when the boat is on the hard and isn't too shabby when out to sea.  I'm luck that my boat is plywood/fibreglass so no issues with faraday shields etc.  External 2m marine antennas aren't easily obtainable here in Australia, I'm certainly interested in any suggestions other APRS yachties might have, especially dual band inc 70cm :)

              73's

              Matthew
              VK5ZM

              On 16 January 2013 15:10, James Ewen <ve6srv@...> wrote:
               

              On Tue, Jan 15, 2013 at 8:42 PM, Matthew Cook vk5zm@...> wrote:

              > Scott if you were to look at low power modes then it would be worth
              > switching to the binary protocol and looking for a GPS module with hot start
              > capabilities. I think it wouldn 't be too hard to then put in a script
              > that allowed us to switch profiles when the boat starts to move, which then
              > switches from a 30min update rate to a smart beaconing routine taylored for
              > yachts/power boats.

              We already have the scripting capability, profile switching based on
              speed, and fixed rate/SmartBeaconing. Using the binary protocol
              however would mean that you would be limited one one specific GPS, or
              series of GPS as each one will have a proprietary communications
              protocol. NMEA is a common language.


              > It's then just a simple matter of switching the HT at
              > the appropriate time. It would also be nice if we could somehow get the
              > PARAM information into the TNC so that APRS.fi can give us pretty graphs of
              > battery volts etc.

              You can do that with scripting right now. Not many places display the
              telemetry parameters. If you are only wanting to get the parameters
              into aprs.fi, you can simply send the parameters once, and they will
              "stick" for a very long time.


              > I'd certainly be willing to buy/build/test such a unit.
              > I've got two boats to test it on (yes I'm greedy and likes my
              > boating/fishing), and a mate of mine has a shiny new sports car that sits in
              > his garage that wants one also. Definitely food for thought.

              Pony up the pennies... you've got 95% of what you are asking for
              sitting on the shelf!

              The OT+ will do everything you want except talk in a proprietary
              binary mode to the GPS of your choice, and poll it for a position.

              --
              James
              VE6SRV




              --
              Matthew
              VK5ZM
              0487 653 245
            • Matthew Cook
              I ve already stumped the pennies into a T2 + Alinco HT for my yacht at least. The scripts were easily written, mind you took me a while to debug. To solve
              Message 6 of 13 , Jan 16, 2013
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                I've already stumped the pennies into a T2 + Alinco HT for my yacht at least.  The scripts were easily written, mind you took me a while to debug.

                To solve this GPS Power/APRS tracker problem I've been working on a MSP430 that sits between the T2 and the GPS.  The MSP430 puts the GPS (ublox) into binary low power mode (hot start) and implements a variable GPS polling period (based upon speed) and then simply tells lies to the T2 every second by sending fake NMEA sentances.  The MSP430 currently adds 2mA to my overall consumption.  I've down to 25-27mA depending on how to look at the AVO.

                The MSP430 sits there and polls the GPS and watches the speed.  If the speed starts to change then the GPS polling period is varied, this should sound familiar?  Yes I've simply copied the SmartBeaconing(TM) algorithm again.

                Anyway if we could get a T3 that can read any one of the GPS units in a low power (and if necessary binary) mode and poll the GPS for a position before transmit then I'd certainly be looking for such a unit.  Programming my MSP430 is a PITA, since I've got to copy the SmartBeaconing parameters out of the T2 and feed them into my software.  It works but it's certainly not production ready, nor do I wish to release/develop this further.  Was just trying to solve the same problem as Marc.

                I hope that the ideas above gives Scott some thoughts as to how this low power GPS mode could be useful.

                I've found the hot start mechanism in the Atmel ublox is pretty good, meaning the positions when polled are coming out as expected.  The prolific chipsets I had no end of trouble with in general.  They were not as well supported as the ublox in terms of others having used them.

                With regard to the GPS, having a unit that can mount on the deck of the boat and sends serial back (hockey puck style) would be preferable to say a GPS module within the T3.  An internal module would require an external antenna with active preamp to get around the cable loss and NF issues, which adds 10-12mA to the overall current consumption; this will blow your power budget.

                The HT and T2 I've hidden under the deck using the HT rubber duck.  I've found that this gets into the local APRS system well when the boat is on the hard and isn't too shabby when out to sea.  I'm luck that my boat is plywood/fibreglass so no issues with faraday shields etc.  External 2m marine antennas aren't easily obtainable here in Australia, I'm certainly interested in any suggestions other APRS yachties might have, especially dual band inc 70cm :)

                73's

                Matthew
                VK5ZM

                On 16 January 2013 15:10, James Ewen <ve6srv@...> wrote:
                 

                On Tue, Jan 15, 2013 at 8:42 PM, Matthew Cook vk5zm@...> wrote:

                > Scott if you were to look at low power modes then it would be worth
                > switching to the binary protocol and looking for a GPS module with hot start
                > capabilities. I think it wouldn 't be too hard to then put in a script
                > that allowed us to switch profiles when the boat starts to move, which then
                > switches from a 30min update rate to a smart beaconing routine taylored for
                > yachts/power boats.

                We already have the scripting capability, profile switching based on
                speed, and fixed rate/SmartBeaconing. Using the binary protocol
                however would mean that you would be limited one one specific GPS, or
                series of GPS as each one will have a proprietary communications
                protocol. NMEA is a common language.


                > It's then just a simple matter of switching the HT at
                > the appropriate time. It would also be nice if we could somehow get the
                > PARAM information into the TNC so that APRS.fi can give us pretty graphs of
                > battery volts etc.

                You can do that with scripting right now. Not many places display the
                telemetry parameters. If you are only wanting to get the parameters
                into aprs.fi, you can simply send the parameters once, and they will
                "stick" for a very long time.


                > I'd certainly be willing to buy/build/test such a unit.
                > I've got two boats to test it on (yes I'm greedy and likes my
                > boating/fishing), and a mate of mine has a shiny new sports car that sits in
                > his garage that wants one also. Definitely food for thought.

                Pony up the pennies... you've got 95% of what you are asking for
                sitting on the shelf!

                The OT+ will do everything you want except talk in a proprietary
                binary mode to the GPS of your choice, and poll it for a position.

                --
                James
                VE6SRV




                --
                Matthew
                VK5ZM
                0487 653 245
              • Scott Miller
                Hi Matthew, I think you ve shared some of the documentation with me before, but it s been a while and I don t remember the details. I d be happy to look over
                Message 7 of 13 , Jan 16, 2013
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                  Hi Matthew,

                  I think you've shared some of the documentation with me before, but it's
                  been a while and I don't remember the details. I'd be happy to look
                  over it again and see if I can incorporate some of that into the T3 and
                  maybe the T2. Turns out one compiler optimization wasn't enabled and I
                  have something like 800 bytes to work with on the T2 now!

                  Scott

                  On 1/16/2013 8:23 PM, Matthew Cook wrote:
                  > I've already stumped the pennies into a T2 + Alinco HT for my yacht at
                  > least. The scripts were easily written, mind you took me a while to debug.
                  >
                  > To solve this GPS Power/APRS tracker problem I've been working on a
                  > MSP430 that sits between the T2 and the GPS. The MSP430 puts the GPS
                  > (ublox) into binary low power mode (hot start) and implements a variable
                  > GPS polling period (based upon speed) and then simply tells lies to the
                  > T2 every second by sending fake NMEA sentances. The MSP430 currently
                  > adds 2mA to my overall consumption. I've down to 25-27mA depending on
                  > how to look at the AVO.
                  >
                  > The MSP430 sits there and polls the GPS and watches the speed. If the
                  > speed starts to change then the GPS polling period is varied, this
                  > should sound familiar? Yes I've simply copied the SmartBeaconing(TM)
                  > algorithm again.
                  >
                  > Anyway if we could get a T3 that can read any one of the GPS units in a
                  > low power (and if necessary binary) mode and poll the GPS for a position
                  > before transmit then I'd certainly be looking for such a unit.
                  > Programming my MSP430 is a PITA, since I've got to copy the
                  > SmartBeaconing parameters out of the T2 and feed them into my software.
                  > It works but it's certainly not production ready, nor do I wish to
                  > release/develop this further. Was just trying to solve the same problem
                  > as Marc.
                  >
                  > I hope that the ideas above gives Scott some thoughts as to how this low
                  > power GPS mode could be useful.
                  >
                  > I've found the hot start mechanism in the Atmel ublox is pretty good,
                  > meaning the positions when polled are coming out as expected. The
                  > prolific chipsets I had no end of trouble with in general. They were
                  > not as well supported as the ublox in terms of others having used them.
                  >
                  > With regard to the GPS, having a unit that can mount on the deck of the
                  > boat and sends serial back (hockey puck style) would be preferable to
                  > say a GPS module within the T3. An internal module would require an
                  > external antenna with active preamp to get around the cable loss and NF
                  > issues, which adds 10-12mA to the overall current consumption; this will
                  > blow your power budget.
                  >
                  > The HT and T2 I've hidden under the deck using the HT rubber duck. I've
                  > found that this gets into the local APRS system well when the boat is on
                  > the hard and isn't too shabby when out to sea. I'm luck that my boat is
                  > plywood/fibreglass so no issues with faraday shields etc. External 2m
                  > marine antennas aren't easily obtainable here in Australia, I'm
                  > certainly interested in any suggestions other APRS yachties might have,
                  > especially dual band inc 70cm :)
                  >
                  > 73's
                  >
                  > Matthew
                  > VK5ZM
                  >
                  > On 16 January 2013 15:10, James Ewen <ve6srv@...
                  > <mailto:ve6srv@...>> wrote:
                  >
                  > __
                  >
                  > On Tue, Jan 15, 2013 at 8:42 PM, Matthew Cook vk5zm@...
                  > <mailto:vk5zm%40bistre.net>> wrote:
                  >
                  > > Scott if you were to look at low power modes then it would be worth
                  > > switching to the binary protocol and looking for a GPS module
                  > with hot start
                  > > capabilities. I think it wouldn 't be too hard to then put in a
                  > script
                  > > that allowed us to switch profiles when the boat starts to move,
                  > which then
                  > > switches from a 30min update rate to a smart beaconing routine
                  > taylored for
                  > > yachts/power boats.
                  >
                  > We already have the scripting capability, profile switching based on
                  > speed, and fixed rate/SmartBeaconing. Using the binary protocol
                  > however would mean that you would be limited one one specific GPS, or
                  > series of GPS as each one will have a proprietary communications
                  > protocol. NMEA is a common language.
                  >
                  >
                  > > It's then just a simple matter of switching the HT at
                  > > the appropriate time. It would also be nice if we could somehow
                  > get the
                  > > PARAM information into the TNC so that APRS.fi can give us pretty
                  > graphs of
                  > > battery volts etc.
                  >
                  > You can do that with scripting right now. Not many places display the
                  > telemetry parameters. If you are only wanting to get the parameters
                  > into aprs.fi <http://aprs.fi>, you can simply send the parameters
                  > once, and they will
                  > "stick" for a very long time.
                  >
                  >
                  > > I'd certainly be willing to buy/build/test such a unit.
                  > > I've got two boats to test it on (yes I'm greedy and likes my
                  > > boating/fishing), and a mate of mine has a shiny new sports car
                  > that sits in
                  > > his garage that wants one also. Definitely food for thought.
                  >
                  > Pony up the pennies... you've got 95% of what you are asking for
                  > sitting on the shelf!
                  >
                  > The OT+ will do everything you want except talk in a proprietary
                  > binary mode to the GPS of your choice, and poll it for a position.
                  >
                  > --
                  > James
                  > VE6SRV
                  >
                  >
                  >
                  >
                  > --
                  > Matthew
                  > VK5ZM
                  > 0487 653 245
                  >
                  >
                • Matthew Cook
                  Hi Scott, I ll go over my notes on the weekend when I get home and send you through some info. I m about 300mi from home at the moment out in the country side
                  Message 8 of 13 , Jan 16, 2013
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                    Hi Scott,

                    I'll go over my notes on the weekend when I get home and send you through some info.

                    I'm about 300mi from home at the moment out in the country side with my trusty laptop, 3G wireless internet modem & embedded development system literally writing and debugging code in a farmers paddock... it's just tipped over +42degC in the shade today :)

                    Anyway more soon.

                    Regards

                    Matthew

                    On 17 January 2013 15:54, Scott Miller <scott@...> wrote:
                    Hi Matthew,

                    I think you've shared some of the documentation with me before, but it's
                    been a while and I don't remember the details.  I'd be happy to look
                    over it again and see if I can incorporate some of that into the T3 and
                    maybe the T2.  Turns out one compiler optimization wasn't enabled and I
                    have something like 800 bytes to work with on the T2 now!

                    Scott

                    On 1/16/2013 8:23 PM, Matthew Cook wrote:
                    > I've already stumped the pennies into a T2 + Alinco HT for my yacht at
                    > least.  The scripts were easily written, mind you took me a while to debug.
                    >
                    > To solve this GPS Power/APRS tracker problem I've been working on a
                    > MSP430 that sits between the T2 and the GPS.  The MSP430 puts the GPS
                    > (ublox) into binary low power mode (hot start) and implements a variable
                    > GPS polling period (based upon speed) and then simply tells lies to the
                    > T2 every second by sending fake NMEA sentances.  The MSP430 currently
                    > adds 2mA to my overall consumption.  I've down to 25-27mA depending on
                    > how to look at the AVO.
                    >
                    > The MSP430 sits there and polls the GPS and watches the speed.  If the
                    > speed starts to change then the GPS polling period is varied, this
                    > should sound familiar?  Yes I've simply copied the SmartBeaconing(TM)
                    > algorithm again.
                    >
                    > Anyway if we could get a T3 that can read any one of the GPS units in a
                    > low power (and if necessary binary) mode and poll the GPS for a position
                    > before transmit then I'd certainly be looking for such a unit.
                    > Programming my MSP430 is a PITA, since I've got to copy the
                    > SmartBeaconing parameters out of the T2 and feed them into my software.
                    > It works but it's certainly not production ready, nor do I wish to
                    > release/develop this further.  Was just trying to solve the same problem
                    > as Marc.
                    >
                    > I hope that the ideas above gives Scott some thoughts as to how this low
                    > power GPS mode could be useful.
                    >
                    > I've found the hot start mechanism in the Atmel ublox is pretty good,
                    > meaning the positions when polled are coming out as expected.  The
                    > prolific chipsets I had no end of trouble with in general.  They were
                    > not as well supported as the ublox in terms of others having used them.
                    >
                    > With regard to the GPS, having a unit that can mount on the deck of the
                    > boat and sends serial back (hockey puck style) would be preferable to
                    > say a GPS module within the T3.  An internal module would require an
                    > external antenna with active preamp to get around the cable loss and NF
                    > issues, which adds 10-12mA to the overall current consumption; this will
                    > blow your power budget.
                    >
                    > The HT and T2 I've hidden under the deck using the HT rubber duck.  I've
                    > found that this gets into the local APRS system well when the boat is on
                    > the hard and isn't too shabby when out to sea.  I'm luck that my boat is
                    > plywood/fibreglass so no issues with faraday shields etc.  External 2m
                    > marine antennas aren't easily obtainable here in Australia, I'm
                    > certainly interested in any suggestions other APRS yachties might have,
                    > especially dual band inc 70cm :)
                    >
                    > 73's
                    >
                    > Matthew
                    > VK5ZM
                    >
                    > On 16 January 2013 15:10, James Ewen <ve6srv@...
                    > <mailto:ve6srv@...>> wrote:
                    >
                    >     __
                    >
                    >     On Tue, Jan 15, 2013 at 8:42 PM, Matthew Cook vk5zm@...
                    >     <mailto:vk5zm%40bistre.net>> wrote:
                    >
                    >      > Scott if you were to look at low power modes then it would be worth
                    >      > switching to the binary protocol and looking for a GPS module
                    >     with hot start
                    >      > capabilities. I think it wouldn 't be too hard to then put in a
                    >     script
                    >      > that allowed us to switch profiles when the boat starts to move,
                    >     which then
                    >      > switches from a 30min update rate to a smart beaconing routine
                    >     taylored for
                    >      > yachts/power boats.
                    >
                    >     We already have the scripting capability, profile switching based on
                    >     speed, and fixed rate/SmartBeaconing. Using the binary protocol
                    >     however would mean that you would be limited one one specific GPS, or
                    >     series of GPS as each one will have a proprietary communications
                    >     protocol. NMEA is a common language.
                    >
                    >
                    >      > It's then just a simple matter of switching the HT at
                    >      > the appropriate time. It would also be nice if we could somehow
                    >     get the
                    >      > PARAM information into the TNC so that APRS.fi can give us pretty
                    >     graphs of
                    >      > battery volts etc.
                    >
                    >     You can do that with scripting right now. Not many places display the
                    >     telemetry parameters. If you are only wanting to get the parameters
                    >     into aprs.fi <http://aprs.fi>, you can simply send the parameters
                    >     once, and they will
                    >     "stick" for a very long time.
                    >
                    >
                    >      > I'd certainly be willing to buy/build/test such a unit.
                    >      > I've got two boats to test it on (yes I'm greedy and likes my
                    >      > boating/fishing), and a mate of mine has a shiny new sports car
                    >     that sits in
                    >      > his garage that wants one also. Definitely food for thought.
                    >
                    >     Pony up the pennies... you've got 95% of what you are asking for
                    >     sitting on the shelf!
                    >
                    >     The OT+ will do everything you want except talk in a proprietary
                    >     binary mode to the GPS of your choice, and poll it for a position.
                    >
                    >     --
                    >     James
                    >     VE6SRV
                    >
                    >
                    >
                    >
                    > --
                    > Matthew
                    > VK5ZM
                    > 0487 653 245
                    >
                    >


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                    --
                    Matthew
                    VK5ZM
                    0487 653 245
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