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T2-301 power supply

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  • Bob Burns W9RXR
    My question kinda tags onto KB9MQU s question about a SAR tracker. I m struggling with how to power the T2-301 s that I purchased. I have some 3.2 AH AGM
    Message 1 of 9 , May 9, 2010
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      My question kinda tags onto KB9MQU's question about a SAR tracker.

      I'm struggling with how to power the T2-301's that I purchased. I
      have some 3.2 AH AGM lead-acid batteries that came out of fire alarm
      panels. They do a great job of powering a T2-301 and will run for
      hours with a 60-second beacon rate using compressed beacons.
      Unfortunately, they are heavy and bulky.

      I remember that Scott showed a compact tracker using the T2-301 at
      Dayton last year. I believe his demo unit was powered with an AA
      battery pack. And that's where I run into a dilemma.

      Duracell alkaline AA cells are rated at 1.5 volts and around 2800 mAH
      (is this number correct?). An 8-cell pack would give me 12 volts. I
      have found 8-cell AA battery holders that are 2 cells by 2 cells by 2
      cells long and holders that are 4 cells by 2 cells by 1 cell long. If
      I could find holder that's a flat pack (8 cells side-by-side) it
      would be fairly easy to package along with a T2-301.

      Sanyo has NiMH AA cells that are rated at 1.2 volts and around 2700
      mAH. An 8-cell pack would only provide 9.6 volts, so I think the
      power output from the T2-301 would suffer. I could wire two 6-cell
      packs in series and get 14.4 volts. Is this overkill?

      What's the better choice? I like the idea of using alkaline cells
      because I can buy them anywhere and don't have to mess with a
      charger. I don't like the idea of tossing used alkaline cells in the
      trash, though.

      What does the group think?

      Bob...
    • Jason KG4WSV
      ... sounds a bit high to me - that s the spec for the energizer AA lithium. Alkaline batteries don t like high current draws. I think alkalines are a losing
      Message 2 of 9 , May 9, 2010
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        On Sun, May 9, 2010 at 4:24 PM, Bob Burns W9RXR <w9rxr_@...> wrote:

        > Duracell alkaline AA cells are rated at 1.5 volts and around 2800 mAH
        > (is this number correct?)

        sounds a bit high to me - that's the spec for the energizer AA lithium.

        Alkaline batteries don't like high current draws. I think alkalines
        are a losing proposition.

        I either can't find my notes or failed to take any, but IIRC an 8 pack
        of energizer AA lithium will run a T2-301 at default power (5W)
        beaconing once a minute for at least 24 hours. A 4 pack of CR123A
        cells (3V lithium camera battery) will go over 12 hours (12 was the
        duration of the test, batteries were not dead at the end of the test).

        It depends on how long and how frequently you want to operate. If
        this is for ballooning or emergency use, e.g. SAR (note: I am not an
        SAR person), for example, I think lithium batteries would be better.
        They are zero maintenance, high capacity, cold-tolerant, and have a
        long shelf life. Rechargeables, on the other hand, require regular
        maintenance - they don't like to sit around discharged, so you need to
        charge them occasionally even if you aren't using them.

        I vaguely recall some discussion here about the minimum voltage for
        the T2-301. I do recall seeing a 7808 regulator when I opened up the
        one that landed in the river, so there's a minimum of 8.6V for
        reliable operation. The actual lower limit may be higher than that.

        -Jason
        kg4wsv
      • Bob Burns W9RXR
        ... Found my source. Duracell Alkaline-Manganese Dioxide tech bulletin. http://www1.duracell.com/oem/Pdf/others/ATB-full.pdf Rated (maybe over-rated?) capacity
        Message 3 of 9 , May 9, 2010
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          At 05:46 PM 5/9/2010, Jason KG4WSV wrote:
          >On Sun, May 9, 2010 at 4:24 PM, Bob Burns W9RXR <w9rxr_@...> wrote:
          >
          > > Duracell alkaline AA cells are rated at 1.5 volts and around 2800 mAH
          > > (is this number correct?)
          >
          >sounds a bit high to me - that's the spec for the energizer AA lithium.

          Found my source. Duracell Alkaline-Manganese Dioxide tech bulletin.

          http://www1.duracell.com/oem/Pdf/others/ATB-full.pdf

          Rated (maybe over-rated?) capacity of the Duracell MN1500 (AA) cell
          is 2.850 AH.

          >Alkaline batteries don't like high current draws. I think alkalines
          >are a losing proposition.

          A point worth considering.

          >I either can't find my notes or failed to take any, but IIRC an 8
          >pack of energizer AA lithium will run a T2-301 at default power (5W)
          >beaconing once a minute for at least 24 hours.

          Useful information. From Energizer's Application manual, the lithium
          cells would seem to be better suited to this application. The shelf
          life, temperature characteristics, and high discharge capability look
          good, too. I'll have to check local stores for availability.

          Just need to find an 8-cell flat-pack battery holder.

          Bob...
        • Jason KG4WSV
          ... Oh, I believe you (and the data sheet). I m sure it s true for _some_ load. Duracell s datasheet has lots more data than the last Energizer datasheet I
          Message 4 of 9 , May 9, 2010
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            On Sun, May 9, 2010 at 5:15 PM, Bob Burns W9RXR <w9rxr_@...> wrote:
            > Found my source. Duracell Alkaline-Manganese Dioxide tech bulletin.
            >
            > http://www1.duracell.com/oem/Pdf/others/ATB-full.pdf
            >
            > Rated (maybe over-rated?) capacity of the Duracell MN1500 (AA) cell
            > is 2.850 AH.

            Oh, I believe you (and the data sheet). I'm sure it's true for _some_
            load. Duracell's datasheet has lots more data than the last Energizer
            datasheet I looked at, but neither of them tell you the current draw
            for that Ah rating. Duracell's got some interesting curves with
            larger (e.g. 275mA) loads that may give a clue to high current
            performance.

            > I'll have to check local stores for availability.

            Check your local discount store's photo department. About $17 per 8
            pack is the best price I've found.

            > Just need to find an 8-cell flat-pack battery holder.

            I wired two 4xAA holders side by side, but it's not an enclosure -
            just something meant to ride inside a balloon payload.

            -Jason
            kg4wsv
          • Bob Burns W9RXR
            ... Scott, what are the dimensions of the 8 AA battery holder you have in the store? https://www.argentdata.com/catalog/product_info.php?products_id=96 I ve
            Message 5 of 9 , May 9, 2010
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              At 06:15 PM 5/9/2010, Bob Burns W9RXR wrote:

              >Just need to find an 8-cell flat-pack battery holder.

              Scott, what are the dimensions of the 8 AA battery holder you have in
              the store?

              https://www.argentdata.com/catalog/product_info.php?products_id=96

              I've found some 8-cell flat-pack holders on-line, but only from
              Aisian distributors who have large minimum orders. The Blossom BH381
              is one example. I'm thinking that a T2-301 and an 8-cell flat-pack
              holder would fit very nicely in something like a Pelican 1030 case.

              Bob...
            • Scott Miller
              I d have to check - it s made by MPD and their site at batteryholders.com should have drawings. For the SAR packs, I forget where I got those holders. I ll
              Message 6 of 9 , May 9, 2010
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                I'd have to check - it's made by MPD and their site at
                batteryholders.com should have drawings.

                For the SAR packs, I forget where I got those holders. I'll have to go
                dig through some invoices.

                Scott

                Bob Burns W9RXR wrote:
                >
                >
                > At 06:15 PM 5/9/2010, Bob Burns W9RXR wrote:
                >
                > >Just need to find an 8-cell flat-pack battery holder.
                >
                > Scott, what are the dimensions of the 8 AA battery holder you have in
                > the store?
                >
                > https://www.argentdata.com/catalog/product_info.php?products_id=96
                > <https://www.argentdata.com/catalog/product_info.php?products_id=96>
                >
                > I've found some 8-cell flat-pack holders on-line, but only from
                > Aisian distributors who have large minimum orders. The Blossom BH381
                > is one example. I'm thinking that a T2-301 and an 8-cell flat-pack
                > holder would fit very nicely in something like a Pelican 1030 case.
                >
                > Bob...
                >
                >
              • Larry Simon
                are you looking for something like this? _____ From:
                Message 7 of 9 , May 9, 2010
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                  are you looking for something like this?
                  <http://www.batteryspace.com/batteryholder8xaasidebysidewith626awgwireleads-rohscompliant.aspx>

                  _____

                  From: tracker2@yahoogroups.com [mailto:tracker2@yahoogroups.com] On Behalf
                  Of Bob Burns W9RXR
                  Sent: Sunday, May 09, 2010 4:58 PM
                  To: tracker2@yahoogroups.com
                  Subject: Re: [tracker2] T2-301 power supply




                  At 06:15 PM 5/9/2010, Bob Burns W9RXR wrote:

                  >Just need to find an 8-cell flat-pack battery holder.

                  Scott, what are the dimensions of the 8 AA battery holder you have in
                  the store?

                  <https://www.argentdata.com/catalog/product_info.php?products_id=96>

                  I've found some 8-cell flat-pack holders on-line, but only from
                  Aisian distributors who have large minimum orders. The Blossom BH381
                  is one example. I'm thinking that a T2-301 and an 8-cell flat-pack
                  holder would fit very nicely in something like a Pelican 1030 case.

                  Bob...
                • Tim Cunningham
                  Forget about Alkaline. Here is a nice reference to some NiMH batteries and chargers for reference you might find helpful, but it is a little dated:
                  Message 8 of 9 , May 9, 2010
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                    Forget about Alkaline.

                    Here is a nice reference to some NiMH batteries and chargers for reference
                    you might find helpful, but it is a little dated:

                    http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM


                    I have tested a few brands myself (NiMH variety) and found that none lived
                    up to their actual ratings. Chargers and batteries have been a variable in
                    my digital camera operation. I finally tossed my charger and upgraded to a
                    more elaborate charger and it indeed made a huge difference in how I group
                    my batteries for camera/flash operation. Some batteries come close to their
                    rated numbers as far as capacity (NiMH type) but I have not seen many in my
                    experience. It only takes one bad link in a chain to cause trouble as well.
                    So, the condition of any battery and its storage capability are important
                    when used in series. I once had some Camedia batteries that really performed
                    many years ago and they lasted the longest as far as the number of recharge
                    cycles. History has not repeated in this area. Manufacturers change their
                    recipe from time to time and you cannot expect the same brand to perform the
                    same either as new batteries are released. I have thrown many of the
                    Duracell 2600mah batteries away due to high impedance failures or failure to
                    live up to the rated capacity. I have been pleased with PowerEx so far, but
                    I just started using their products in the past 6 months.

                    I have a Maha MH-C9000 charger that I have been very pleased with using to
                    keep my batteries in good condition and report the health by analyzing the
                    batteries. This has proved its worth many times to keep my camera and flash
                    running on extended periods. I carry several sets of batteries grouped
                    according to their actual (not rated) storage capacity. It makes enough
                    difference to do this when you need reliable and repeatable performance.

                    Lithium's will be the best bet.

                    All rechargeables need to be topped off or recharged before prior to use due
                    to shelf life limitations if you want/need/demand maximum performance. For
                    critical operation you need to analyze your batteries (put them to the test)
                    before you put them into operation to avoid any surprises.


                    73's,

                    Tim - N8DEU



                    ----- Original Message -----
                    From: "Jason KG4WSV" <kg4wsv@...>
                    To: <tracker2@yahoogroups.com>
                    Sent: Sunday, May 09, 2010 4:46 PM
                    Subject: Re: [tracker2] T2-301 power supply


                    > On Sun, May 9, 2010 at 4:24 PM, Bob Burns W9RXR <w9rxr_@...>
                    > wrote:
                    >
                    >> Duracell alkaline AA cells are rated at 1.5 volts and around 2800 mAH
                    >> (is this number correct?)
                    >
                    > sounds a bit high to me - that's the spec for the energizer AA lithium.
                    >
                    > Alkaline batteries don't like high current draws. I think alkalines
                    > are a losing proposition.
                    >
                    > I either can't find my notes or failed to take any, but IIRC an 8 pack
                    > of energizer AA lithium will run a T2-301 at default power (5W)
                    > beaconing once a minute for at least 24 hours. A 4 pack of CR123A
                    > cells (3V lithium camera battery) will go over 12 hours (12 was the
                    > duration of the test, batteries were not dead at the end of the test).
                    >
                    > It depends on how long and how frequently you want to operate. If
                    > this is for ballooning or emergency use, e.g. SAR (note: I am not an
                    > SAR person), for example, I think lithium batteries would be better.
                    > They are zero maintenance, high capacity, cold-tolerant, and have a
                    > long shelf life. Rechargeables, on the other hand, require regular
                    > maintenance - they don't like to sit around discharged, so you need to
                    > charge them occasionally even if you aren't using them.
                    >
                    > I vaguely recall some discussion here about the minimum voltage for
                    > the T2-301. I do recall seeing a 7808 regulator when I opened up the
                    > one that landed in the river, so there's a minimum of 8.6V for
                    > reliable operation. The actual lower limit may be higher than that.
                    >
                    > -Jason
                    > kg4wsv
                    >
                  • Bob Burns W9RXR
                    ... Exactly. Thanks, Larry! ... Check. ... I ll be stopping at Wal-Mart (ugh) this evening to see what they have. Bob...
                    Message 9 of 9 , May 10, 2010
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                      At 08:31 PM 5/9/2010, Larry Simon wrote:
                      >are you looking for something like this?
                      ><http://www.batteryspace.com/batteryholder8xaasidebysidewith626awgwireleads-rohscompliant.aspx>

                      Exactly. Thanks, Larry!

                      At 01:19 AM 5/10/2010, Tim Cunningham wrote:
                      >Forget about Alkaline.

                      Check.

                      >Lithium's will be the best bet.

                      I'll be stopping at Wal-Mart (ugh) this evening to see what they have.

                      Bob...
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