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FR - Princeton Tec Quad Headlamp - Roger Caffin

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  • Roger Caffin
    Hi Will The HTML is in the Test folder as usual, at:
    Message 1 of 17 , Dec 28, 2006
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      Hi Will

      The HTML is in the Test folder as usual, at:
      http://www.backpackgeartest.org/reviews/test/TESTS/FR%20-%20Princeton%20Tec%20Quad%20Headlamp%20-%20Roger%20Caffin/

      Enjoy ... :-)

      Cheers and Happy New Year
      Roger Caffin
      ---------------------------------------------------
      Field Report - Princeton Tec Quad Headlamp
      Roger Caffin
      28-Dec-2006

      Reviewer Details
      Reviewer: Roger Caffin
      Age: 61
      Gender: M
      Weight: 63 kg (139 lb)
      Height: 167 cm (67")
      Email address: r dot [surname] at acm dot org
      Home: Sydney, Australia

      Backpacking Background

      I started bushwalking at 14 and took up rock climbing at University with the girl who became my wife and my permanent
      walking partner. Ski touring and canyoning followed. Winter and summer, we prefer long hard trips by ourselves: about a
      week in Australia, up to two months in Europe/UK. We prefer fast and light in unfrequented trackless country. We would
      be out walking and skiing for at least three months a year. We have now moved to lightweight gear, much to our backs'
      relief. I designed and made much of our lightweight gear myself.

      I am also the maintainer of the Australian aus.bushwalking FAQ web site www.bushwalking.org.au/FAQ/.

      Product Information
      Manufacturer: Princeton Tec
      Manufacturer URL: www.princetontec.com/
      Year of manufacture: assumed 2006
      Country of manufacture: China
      Colour: Blue & Yellow housing, black and grey headband
      Batteries: 3 AAA, any sort
      Listed weight: 96 g (3.39 oz)
      Actual weight: 96 g (3.39 oz)
      MSRP: na


      Product Claims
      * 4-mode switch
      * 4 ultra-bright LEDs
      * Waterproof to 1 m
      * Regulated LEDs
      * Hinged bracket
      * Battery power meter
      * The advertising shows a broad head-strap

      Background

      I am a consultant research scientist, and have spent many years working in the area of computer image analysis. One of
      the most fundamental issues in image analysis is getting the lighting right, so I have spent a lot of time working on
      designing and testing lighting systems. In addition I have made my own small lightweight Light Emitting Diode (LED)
      headlamps using miniature switch-mode power supplies which I have designed and built. So one might say I have a bit of
      an interest in the technical side of headlamps. Finally, I do have a fairly good research laboratory of my own.

      Laboratory Testing

      It seemed to me that this is the sort of thing which can be tested in the laboratory as well as in the field, so I
      decided to investigate the power supply and the light regulation on the bench. Specifically, I wanted to find out what
      sort of current drain the headlamp puts on the batteries at the different power levels. This would help me estimate the
      likely battery life, given that I have data on battery performance. Along the way I hoped to find out a bit more about
      what sort of regulation system is used in this headlamp, and how efficient it is.

      As batteries get used up the voltage they deliver decays. When the output voltage gets low enough one says the battery
      has died. The higher the current drain, the faster this happens. So the obvious test is to monitor the current into the
      headlamp as the voltage is varied. It might be expected that as the voltage decreases the output power or light level
      would decrease, so this should be monitored at the same time. Ideally it would be nice to know how much power is being
      delivered to the LEDs as well, but I have not yet found a way into the 'insides' of the unit yet, so this has not been
      possible. However, the light coming out does give some guidance to this.

      I considered mapping out the brightness field, but really I could not see that this would be of all that much use in
      practice. The headlamp uses Nichia super-bright white LEDs (according to information from Princeton Tec obtained
      elsewhere), and the field from the headlamp is dictated by those LEDs. Instead I will comment on the usefulness of the
      light field in the Field Testing section.

      Experimental Setup

      I opened up the battery case by undoing the single screw at the back and then mounted the headlamp on an optical bench,
      as shown to the right. I supplied power to the battery case from an external variable power supply, through a current
      meter, and I monitored the voltage at the battery case connections as well. Some distance away I positioned the sensor
      for a Lux Meter. This is essentially a light meter, but with a filter designed to match the response of the human eye.

      At this stage I should point out that while the measurements of volts, milliamps and power are entirely reproducible by
      someone else, the measurements of light intensity (or Lux) are not. This is because even a small change in the alignment
      of the headlamp to the sensor or in the distance between the two will cause a change in the 'scale factor'. So someone
      else doing the same measurements would get different numbers for the Lux readings - but they would get the same sort of
      curves. My discussions will therefore focus on the behaviour of the light output, not on the numerical values. This will
      become clearer as I go.

      Measurements

      The basic results I obtained are shown here. The blue lines show the current as a function of the voltage at the battery
      case terminals. The red lines show the light output as a function of voltage at the battery case terminals. The curves
      come in three pairs: 'H' for high power, 'M' for medium power, and 'L' for low power. These are the three power levels
      the headlamp provides. I did not try measuring the flashing mode.

      The headlamp uses three AAA cells: Duracell alkaline ones were provided. These should provide slightly more than 1.5
      volts each when new, or a fraction over 4.6 volts total. Typically the 'end of life' for alkaline batteries is defined
      as 0.9 volts, making 2.7 volts total. So my measurements were made over the range from 4.6 volts to 2.8 volts, with a
      'zero' reading at 2.2 volts.

      I should also explain that the nominal voltage required to drive a white LED at the nominal current is 3.6 volts.
      However, the voltage/current curve for a white LED is not sharp: it actually looks very much like the smooth curve seen
      here between 2.5 and 3.8 volts for the H case. Technically this is an exponential curve, but no matter. The nominal
      current rating for a standard LED is 20 mA, and LEDs have something like a 50,000 hour life at this current. I believe
      the High setting puts about 75 mA through each LED, which is going to stress the heat dissipation a bit and reduce the
      life of the LEDs somewhat. Well, even if it reduces the life to 5,000 hours (down to 1/10th of the nominal value), that
      is probably longer than most users will ever need.

      What these results tell me about the headlamp is as follows. Provided the batteries deliver more than the required
      voltage, the internal regulator limits the current supplied to the LEDs to a roughly constant value. Well - 'roughly
      constant'. In the H case the regulation is not very good, so the current to the LEDs varies a bit as the voltage falls,
      but in the M and L cases the LED current is maintained at a fairly constant level. Investigation with an oscilloscope
      showed that in the H case above 4.2 volts there is a high-frequency ripple on the supply, but this ripple does not
      appear under any other conditions. This means there are actually three different operating regimes for the power supply
      inside the headlamp, as follows.
      1. High power, high supply voltage, ie above a 4.2 V threshold (to the right of the 'H')
      The power supply enters a switching mode of operation. This is consistent with the rise in supply current as the battery
      voltage falls.
      2. Medium and Low power, above a threshold of about 3.6 volt (to the right of the 'M' and 'L').
      The power supply acts as a linear regulator, dissipating the excess voltage as heat, (ie wasting the excess voltage).
      3. All three power levels, below their thresholds down to about 2.5 volt.
      Straight pass-through with essentially no regulation - at lower voltages.

      These results make sense out of the Princeton Tec specifications for burn time, which talk about a 'sophisticated
      current-regulating circuit that maintains initial brightness as long as the batteries have sufficient voltage'. The
      specifications go on to mention both 'Regulated LEDs' and 'Unregulated LEDs'. The regulated regimes, which by their
      specifications have a rather short period, correspond to the first two regimes above.

      Finally, I tested the little red 'Battery Power Meter LED' found under the white LEDs. The specifications state that 'If
      the headlamp is turned off and the battery voltage is low, the red ... LED ... will start blinking'. This does indeed
      happen when the total battery voltage falls below 2.7 volt. This corresponds to a single battery voltage of 0.9 volt,
      which is a very common 'end-of-life' value. I found I had to remove power from the headlamp to stop the red LED from
      blinking.

      Battery Characteristics

      It seemed to me that it might be useful to put the above measurements into context by looking at battery
      characteristics. I have put typical cell ratings for the common Eveready Alkaline AAA cell and the new Eveready Lithium
      AAA cell to the right here. Several things stand out from these curves.
      * The first, which is fairly well known, is that the new Eveready Lithium cells have more capacity than the Alkaline
      cells. This is particularly apparent at the higher current levels. They may be dearer, but in many cases they are well
      worth the money. This means they are going to last a lot longer in a headlamp, especially at the higher power levels.
      * Less obvious is the different behaviour of the two chemistries. The output voltage from the Alkaline chemistry decays
      quite lot as the cell is used up, falling steadily from almost 1.6 volt to and end-of life at 0.8 volt. In the Lithium
      case the voltage drops slightly from 1.6 volt to 1.5 volt right at the start, but then stays almost constant almost to
      the end of life, falling to only 1.4 volt. After this the end is fairly swift.
      * Also well known to some is that fact that the Alkaline cells die at freezing point, while the Lithium cells still
      have nearly 70% of their capacity at -20 C (-4 F). This means I can expect my headlamp to function quite well at night
      in the snow with Lithium cells, but maybe not with Alkaline cells. This has happened to me in the past, when I found
      that the Alkaline cells lasted about 5 minutes!

      The above details help explain why the Princeton Tec specifications claim the headlamp will run in regulated mode at
      High power for 4 hours on Lithium cells but only for 1 hour on Alkaline cells. The details also explain why the headlamp
      will run for a lot longer in UNregulated mode (with a decaying output brightness) with Alkaline cells than with Lithium
      cells: the Lithium cells hold their voltage up right to the end (thereby staying in the regulated region), but the
      Alkaline cells don't.

      The curves also point out a very slight problem with the low battery threshold of 0.9 volt. An Alkaline cell still has a
      small amount of power left at 0.9 volt - not much, to be sure. But a Lithium cell at 0.9 volt has almost no power left
      at all! This means that I might have some minutes left to fossick around in my gear to find replacement batteries if I
      am running on Alkalines, but maybe not if I am running on Lithiums. In reality I don't think the red LED has much value
      in the field. It isn't hard to see when the headlamp is losing power: everything starts to get a bit dimmer, and
      changing between power settings has no effect. And that is before I turn the headlamp off! If I can't tell that the
      batteries are dying some considerable time before the red LED starts blinking, then I might as well give up.

      Battery Case

      The battery case has what looks like a good O-ring seal, as shown here. I have not pressure-tested this, but my
      experience with O-ring seals on other equipment leaves me happy with the design of this one.

      The battery connections seem to be designed so that putting a battery in reversed should not work. There is a recess at
      each positive terminal in the battery case ('Recessed +ve terminal') protected by surrounding plastic. The recess should
      only be spanned by the protruding lump on the positive end of the AAA cell ('+ve end with lump'). However, I found that
      the negative end of the AAA cells provided with the headlamp could make an unwanted contact when inserted reversed
      ('Unwanted connection'). This is illustrated by the middle cell, which has been inserted into its slot back to front.

      This is a distinct pity as a very slight modification to the metal tabs at the positive terminals would prevent this.
      All that is needed is for the dimple on the tab to be reduced in height by about 1 mm (0.040") and the gap in the
      plastic reduced in width by about the same amount. This would mean that the shoulder of the battery at the wide negative
      end of the cell hits the plastic around the recessed terminal first. With this slight modification it would still be
      possible to insert the cells in the wrong direction, but they would not make electrical connection and there would be no
      risk to the electronics or the LEDs.

      In the meantime I can still load the batteries by touch in the dark, making sure I put the flatter end of each cell
      (Flat -ve end) against the spring (Spring -ve terminal) in each cell slot.

      Summary from Laboratory Testing

      Now I know what is inside the headlamp. There is a regulator of sorts, but it is a rather simple one which does not
      really make the best use of the power available in the cells in my (professional) opinion. For better performance a
      genuine switch-mode regulator would be required. Against that I have to balance the typical retail price for the Quad of
      between US$26 and US$36: it costs me almost that much just for the components to make a genuine switch-mode regulator
      for an application such as this! Princeton Tec has achieved a fair bit for the low price.

      I must make it clear that the current-regulator used in the Quad does work, and it does limit the voltage applied to the
      LEDs so they can have a long life. Pushing about 75 mA through each white LED at the High setting is stressing them a
      bit, but the other settings are no problem. I should point out that it is very likely that with alkaline cells more time
      will spent in the unregulated mode than in the regulated mode. With lithium cells the regulated time would be much
      longer relative to the unregulated time.

      I am going to be a trifle pedantic here and say that calling this a 'fully regulated' headlamp would not be correct.
      However, Princeton Tec does not claim this; the company only claims that 'The Quad uses a sophisticated
      current-regulating circuit that maintains initial brightness as long as the batteries have sufficient voltage.' In my
      opinion this is a correct description of what the Quad offers. It's just that only the lithium cells can maintain that
      'sufficient voltage' for very long.

      I note that another well-known manufacturer of headlamps has come out (on their web site) against the use of lithium
      cells, despite their obvious advantages of capacity and low temperature operation. It seems that the current-limiting
      mechanism used by this other brand cannot handle the higher power of the lithium cells and the headlamps can overheat
      and be damaged. Well, Princeton Tec not only 'allows' the use of lithium cells, but the company gives performance
      figures for them. I applaud this.

      All three settings are bright. I can see the change in light output when I switch between the three settings. However, I
      also know that humans have some difficulty seeing anything much less than a factor of two in a change in brightness. The
      Medium and Low settings are barely this much different. A Low setting considerably dimmer than what is provided would be
      of greater value. I know I normally work with a much dimmer light around camp when I am using the headlamps I have made
      myself.

      Field Testing

      I have taken the Princeton Tec Quad headlamp on a number of long trips during the Field Test period. These have been at
      altitudes from sea level to about 1000 m (3,300'). Temperatures have ranged from about freezing to about 30 C (86 F).
      Fortunately, none of these trips have required that I travel by night very far, but I have tried wandering around the
      campsite at night with the headlamp. The scrub around many of our campsites has been fairly thick rather than open
      grassland. Somewhat fortuitously, most of these trips have had no moon in the evening, so the headlamp really has been
      needed. These outside uses have required the headlamp to illuminate at a moderate distance of a few metres (yards).

      I have also used the headlamp to cook dinner by inside the tent on those many occasions when our days have ended a bit
      late in the evening. There has been enough light to get the tent up, but not enough by the time I had got the stove out.
      These uses have required short-range illumination of about half a metre (yard).

      In both outside and inside use I found that the lowest brightness was quite sufficient for me. In fact I would have been
      quite happy with an even lower brightness than the headlamp can offer. A lower brightness would mean a longer battery
      life of course.

      One thing I did find during use inside the tent was that it was very easy for me to dazzle my wife accidentally, even at
      the lowest brightness. I was able to reduce this problem by adjusting the tilt of the headlamp to be very much downwards
      rather than forwards. The stepped adjustment mechanism the headlamp offers proved to be quick, convenient and stable.
      The broad headstrap or strip of elastic held the headlamp on my head quite stably as well, so the 'pointing' was stable
      in general. The downward tilt is shown in the picture here. Of course, the flash on the camera has washed out the beam.

      Very late in the evening after dinner when getting ready to go to sleep I found it was more convenient to hang the
      headlamp from a 'skyhook' at the roof of my tent, pointing downwards, although this required some ingenuity with the
      broad headstrap. It does not offer a simple method of doing this, so I had to tie an overhand knot with the band. It
      worked fine.

      I have experimented a bit with the switch itself. It can actually be quite hard to sense because it has virtually no
      protrusion sticking up. This is presumably designed to minimise the chances of accidental activation in a pack. I dare
      say that over time and with more practice finding the switch might become easier, but it was a bit tricky at first.
      Eventually I found that I could find it not by position but by first locating the side with the battery case screw, then
      rubbing my finger across the top surface. The compliant rubber yellow seal has much more friction than the plastic case,
      so it feels different and can be located even with gloves on.

      I do have to report that the idea of the almost-recessed on-switch seems good but has failed at least once. That is, I
      did find a glow from the bottom of my pack once: the switch had been activated inside my pack and the headlight had been
      glowing away there for some time. This could be very embarrassing if the batteries end up flat just when I need the
      headlight most. For this reason I always put an interlock on the headlights I make: something like a slip of plastic
      inserted between a battery terminal and the contact to prevent activation. However, I can't see any good way of doing
      this here without substantial modification to the headlamp shell. That would remove the waterproof feature. I could of
      course remove a battery each morning before packing the headlamp away - a lot more work which often does not get done.

      A Small Annoyance

      While overall experience with the headlamp has been fairly good, it does have one feature which is very annoying. When I
      switch it on, it goes to the brightest setting - and this is too bright for me. Every time I had to give the switch not
      one click but three, with my hand over the front of the headlamp to avoid dazzling myself and my wife. It would be ever
      so simple to reverse the settings in the design of the regulator chip so the first click gives the lowest setting. This
      is not the only headlamp with this fault.

      A change in the order of settings would also prevent me from over-running the three clicks to four, thereby getting that
      infernal flashing bright setting. Frankly, I hate that flashing! I would dearly love it to be replaced by a much dimmer
      setting again. A nice idea on the designer's desk perhaps, but a menace in the field.

      Summary so far

      Things I have been looking at include the following:
      * Comfort of the design on my head: the headlamp itself and the webbing, and any tendency to fall down over my eyes
      It is just a bit heavy at the front and might be better with a very light strap over the top of my head, but this is
      marginal.
      * Ease of switching, especially with gloves on The switch is easy enough to operate, but a bit harder to locate in the
      dark. This is only marginal.
      * Ease of putting it on and getting it adjusted
      This is easy to do as the battery case screw is easy to identify in the dark, and the webbing is broad.
      * Stability of the tilt mechanism
      Very good

      * Effectiveness of the broad beam
      A shade broad for outside use at low beam, but fine for inside use. No complaints.
      * Whether the dimmest setting will preserve some night vision
      It's a bit bright for this.
      * What settings are needed for walking around outside in the dark (eg for a trip to the loo)
      Only the lowest setting.
      * How much of my tent interior is lit by the broad beam
      Quite enough for cooking dinner and getting to bed.
      * What possible use is the flash mode??
      No earthly use at all for me.

      * Battery life: 'regulated' vs 'overall'
      I am economical in my use of a light in general. So far, I am still on the original batteries. The light still seems to
      be regulated.
      * Ease of battery replacement
      Pretty simple in the field. The buckle works fine to slacken the battery case screw - and is needed in practice. The
      O-ring stays in place. Loading in the dark is possible by touch.
      * Reliability of the battery case and contacts
      So far so good - but it is always battery leakage and the subsequent corrosion which matters here.
      * Effect of battery aging on the light
      Not noticed in the field so far.
      * Value of the battery life indicator
      Well, I have never bothered to check it in the field.

      * Lifetime of the switches over the Test period
      So far they are working just fine.
      * Durability of the elastic webbing
      It's rather nice webbing, and shows no aging so far.
      * Ease of adjustment and stability of adjustment of the webbing
      Adjustment is easy, although I have not had to attend to this very often. The arrangement seems quite stable.
      * Range of the tilt, and whether it reaches high and low enough
      This is fine.

      Recommendations for Improvement
      * Make the dimmest setting the first one rather than the last one.
      * Convert the flash mode to a dimmer mode.
      * Put a slightly larger bump on the compliant switch cover.
      * Modify the battery case connections slightly so reversed connection is not possible.
    • Jerry Goller
      The flashing mode is an emergency signal. That is why it is the brightest setting. It can be seen for many miles at night and is hard to mistake for any other
      Message 2 of 17 , Dec 30, 2006
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        The flashing mode is an emergency signal. That is why it is the brightest
        setting. It can be seen for many miles at night and is hard to mistake for
        any other type of light.

        Jerry

        http://www.BackpackGearTest.org : the most comprehensive interactive gear
        reviews and tests on the planet.

        -
        * Convert the flash mode to a dimmer mode.
      • Roger Caffin
        Hi Jerry ... Oh, I know that! But it is so damn annoying when you activate it at night accidentally, when trying to turn the headlamp off. You end up losing
        Message 3 of 17 , Dec 31, 2006
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          Hi Jerry

          > The flashing mode is an emergency signal. That is why it is the
          > brightest setting. It can be seen for many miles at night and is
          > hard to mistake for any other type of light.
          Oh, I know that!

          But it is so damn annoying when you activate it at night accidentally, when trying to turn the headlamp off. You end up
          losing your night vision.

          And it is redundant anyhow. I can emulate the effect by passing my hand across the front of the light regularly - should
          I ever need it. I am sure the designer of the electronic chip thought he was being terribly clever when he made it the
          fourth option; I am equally sure he never field tested it himself in the backcountry.

          So if you compare the probability of needing a flashing strobe with the sheer annoyance factor of accidentally
          trigggering it, and add in the simplicity of making a flashing light with your hand, I say it is a bad design. Imho.

          Cheers, and happy New Year
          Roger
        • Jerry Goller
          Well, never having shot myself in the face with it in any mode, I can t say I ve ever had a problem with it..... ;o) I always have mine on my head when I
          Message 4 of 17 , Dec 31, 2006
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            Well, never having shot myself in the face with it in any mode, I can't say
            I've ever had a problem with it..... ;o)

            I always have mine on my head when I turn it on or off. I was laying in a
            tent the other night and thinking about making a cord to hang it from the
            ceiling loops like you mentioned.

            I always thought the strobe mode would be a good thing if I was sufficiently
            incapacitated to need rescue. I could just lay there at night and point it
            up. I imagine a chopper would home in on it fairly quickly. They are using
            thermal imaging more and more here for night search. I'd think one on strobe
            would show up like a champ on one of those.

            I do agree with reversing the order running from low to high to strobe,
            though. I find the low setting just about right for me but having to cycle
            through every time is mildly annoying. I imagine that a lot people use them
            on high though... Wouldn't want the monsters to get them.... ;o)

            But then, I use a Princeton Tec Apex on spot and on high when snow shoeing
            at night. We have lots of canyons with fairly sharp roll offs and canyons
            and draws with steep slopes. In deep snow I want to know well in advance
            what I am walking out on, or into. I've been pulled down a slope by my pulk
            more than once.

            Jerry





            http://www.BackpackGearTest.org : the most comprehensive interactive gear
            reviews and tests on the planet.

            -----Original Message-----
            From: backpackgeartesters@yahoogroups.com
            [mailto:backpackgeartesters@yahoogroups.com] On Behalf Of Roger Caffin
            Sent: Sunday, December 31, 2006 1:37 PM
            To: backpackgeartesters@yahoogroups.com
            Subject: [backpackgeartesters] Re: FR - Princeton Tec Quad Headlamp - Roger
            Caffin

            Hi Jerry

            > The flashing mode is an emergency signal. That is why it is the
            > brightest setting. It can be seen for many miles at night and is hard
            > to mistake for any other type of light.
            Oh, I know that!

            But it is so damn annoying when you activate it at night accidentally, when
            trying to turn the headlamp off. You end up losing your night vision.

            And it is redundant anyhow. I can emulate the effect by passing my hand
            across the front of the light regularly - should I ever need it. I am sure
            the designer of the electronic chip thought he was being terribly clever
            when he made it the fourth option; I am equally sure he never field tested
            it himself in the backcountry.

            So if you compare the probability of needing a flashing strobe with the
            sheer annoyance factor of accidentally trigggering it, and add in the
            simplicity of making a flashing light with your hand, I say it is a bad
            design. Imho.

            Cheers, and happy New Year
            Roger





            Yahoo! Groups Links
          • Shane Steinkamp
            ... sufficiently ... strobe ... Actually, no. At night that beacon would be very easily found visibly, but LED does not put off IR at all. This is a
            Message 5 of 17 , Dec 31, 2006
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              > I always thought the strobe mode would be a good thing if I was
              sufficiently
              > incapacitated to need rescue. I could just lay there at night and point it
              > up. I imagine a chopper would home in on it fairly quickly. They are using
              > thermal imaging more and more here for night search. I'd think one on
              strobe
              > would show up like a champ on one of those.

              Actually, no. At night that beacon would be very easily found visibly, but
              LED does not put off IR at all. This is a consideration when selecting a
              tactical light for the military and LE. You can't put an IR filter on an
              LED light because visible spectrum LEDs don't put off any IR at all. Night
              vision is totally blind to it. You can get infrared LEDs, but they're
              special.

              Of course you also assume that someone would actually come looking for you.
              I sometimes suspect that my family wouldn't report me missing if I was...

              Shane
            • Jerry Goller
              Ah, good point. I hadn t considered that. But they also look in the visible range so I still think they d see it pretty quick and investigate. Kate likes me so
              Message 6 of 17 , Dec 31, 2006
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                Ah, good point. I hadn't considered that. But they also look in the visible
                range so I still think they'd see it pretty quick and investigate.

                Kate likes me so she would report me missing. That would be cheaper than
                paying for day care.....

                Jerry


                http://www.BackpackGearTest.org : the most comprehensive interactive gear
                reviews and tests on the planet.

                -----Original Message-----
                From: backpackgeartesters@yahoogroups.com
                [mailto:backpackgeartesters@yahoogroups.com] On Behalf Of Shane Steinkamp
                Sent: Sunday, December 31, 2006 3:52 PM
                To: backpackgeartesters@yahoogroups.com
                Subject: Re: [backpackgeartesters] Re: FR - Princeton Tec Quad Headlamp -
                Roger Caffin

                > I always thought the strobe mode would be a good thing if I was
                sufficiently
                > incapacitated to need rescue. I could just lay there at night and
                > point it up. I imagine a chopper would home in on it fairly quickly.
                > They are using thermal imaging more and more here for night search.
                > I'd think one on
                strobe
                > would show up like a champ on one of those.

                Actually, no. At night that beacon would be very easily found visibly, but
                LED does not put off IR at all. This is a consideration when selecting a
                tactical light for the military and LE. You can't put an IR filter on an
                LED light because visible spectrum LEDs don't put off any IR at all. Night
                vision is totally blind to it. You can get infrared LEDs, but they're
                special.

                Of course you also assume that someone would actually come looking for you.
                I sometimes suspect that my family wouldn't report me missing if I was...

                Shane




                Yahoo! Groups Links
              • Brian
                HEY there are other list for these types of discussions..... Brian
                Message 7 of 17 , Dec 31, 2006
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                  HEY there are other list for these types of discussions.....

                  Brian

                  On 12/31/06, Jerry Goller <ChiefModerator@...> wrote:
                  > Ah, good point. I hadn't considered that. But they also look in the visible
                  > range so I still think they'd see it pretty quick and investigate.
                  >
                  > Kate likes me so she would report me missing. That would be cheaper than
                  > paying for day care.....
                  >
                  > Jerry
                  >
                • Jerry Goller
                  I d complain to the owner if I were you...... ;o) Jerry http://www.BackpackGearTest.org : the most comprehensive interactive gear reviews and tests on the
                  Message 8 of 17 , Dec 31, 2006
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                    I'd complain to the owner if I were you...... ;o)

                    Jerry


                    http://www.BackpackGearTest.org : the most comprehensive interactive gear
                    reviews and tests on the planet.

                    -----Original Message-----
                    From: backpackgeartesters@yahoogroups.com
                    [mailto:backpackgeartesters@yahoogroups.com] On Behalf Of Brian
                    Sent: Sunday, December 31, 2006 4:58 PM
                    To: backpackgeartesters@yahoogroups.com
                    Subject: Re: [backpackgeartesters] Re: FR - Princeton Tec Quad Headlamp -
                    Roger Caffin

                    HEY there are other list for these types of discussions.....

                    Brian

                    On 12/31/06, Jerry Goller <ChiefModerator@...> wrote:
                    > Ah, good point. I hadn't considered that. But they also look in the
                    > visible range so I still think they'd see it pretty quick and investigate.
                    >
                    > Kate likes me so she would report me missing. That would be cheaper
                    > than paying for day care.....
                    >
                    > Jerry
                    >



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                  • Brian
                    Was hopin the new list moderator would cover it... Brian
                    Message 9 of 17 , Dec 31, 2006
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                      Was hopin the new list moderator would cover it...

                      Brian

                      On 12/31/06, Jerry Goller <ChiefModerator@...> wrote:
                      > I'd complain to the owner if I were you...... ;o)
                      >
                      > Jerry
                      >
                    • Roger Caffin
                      Hi Jerry ... Works moderately well. The narrow beam limits the spread, but it sure is better than nothing. Put something white on the floor to reflect. ...
                      Message 10 of 17 , Jan 1, 2007
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                        Hi Jerry

                        > I always have mine on my head when I turn it on or off. I was laying in a
                        > tent the other night and thinking about making a cord to hang it from the
                        > ceiling loops like you mentioned.
                        Works moderately well. The narrow beam limits the spread, but it sure is better than nothing. Put something white on the
                        floor to reflect.

                        > I always thought the strobe mode would be a good thing if I was sufficiently
                        > incapacitated to need rescue. I could just lay there at night and point it
                        > up. I imagine a chopper would home in on it fairly quickly.
                        Probably. The flash on a camera also works well for this.

                        > They are using thermal imaging more and more here for night search.
                        > I'd think one on strobe would show up like a champ on one of those.
                        NO.
                        Thermal imaging looks for infra red radiation, such as given off by your body. The white LEDs emit NO infra red
                        radiation worth even thinking about. They would be invisible to an IR scanner.

                        > In deep snow I want to know well in advance
                        > what I am walking out on, or into.
                        :-)
                        Been over a few cornices in fog skiing ... :-)

                        Cheers
                        Roger
                        PS for Shane: it wasn't Rick, it might be Coy who was picked for the fourth spot I think.
                      • Shane Steinkamp
                        Soulless mind slave, dude. Even *I*, with mystical and amazing abilities cannot buck the boss on his own list. There are only two moderators who each hold a
                        Message 11 of 17 , Jan 2, 2007
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                          Soulless mind slave, dude. Even *I*, with mystical and amazing abilities
                          cannot buck the boss on his own list. There are only two moderators who
                          each hold a 'buck the boss one time free' card, and I ain't one of those.

                          Shane

                          > Was hopin the new list moderator would cover it...

                          > > I'd complain to the owner if I were you...... ;o)
                        • Brian
                          True...dont be afraid to buck the boss...I m doing it at werk now..course I may not have a job much longer.... Brian
                          Message 12 of 17 , Jan 2, 2007
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                            True...dont be afraid to buck the boss...I'm doing it at werk
                            now..course I may not have a job much longer....

                            Brian

                            On 1/2/07, Shane Steinkamp <shane@...> wrote:
                            > Soulless mind slave, dude. Even *I*, with mystical and amazing abilities
                            > cannot buck the boss on his own list. There are only two moderators who
                            > each hold a 'buck the boss one time free' card, and I ain't one of those.
                            >
                            > Shane
                            >
                            > > Was hopin the new list moderator would cover it...
                            >
                            > > > I'd complain to the owner if I were you...... ;o)
                            >
                          • Jason Boyle
                            nah it is hard to fire government employees.. oh wait your a white male, never mind. jason ... abilities ... moderators who ... of those.
                            Message 13 of 17 , Jan 2, 2007
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                              nah it is hard to fire government employees.. oh wait your a white
                              male, never mind.

                              jason


                              --- In backpackgeartesters@yahoogroups.com, Brian <tannehillclan@...>
                              wrote:
                              >
                              > True...dont be afraid to buck the boss...I'm doing it at werk
                              > now..course I may not have a job much longer....
                              >
                              > Brian
                              >
                              > On 1/2/07, Shane Steinkamp <shane@...> wrote:
                              > > Soulless mind slave, dude. Even *I*, with mystical and amazing
                              abilities
                              > > cannot buck the boss on his own list. There are only two
                              moderators who
                              > > each hold a 'buck the boss one time free' card, and I ain't one
                              of those.
                              > >
                              > > Shane
                              > >
                              > > > Was hopin the new list moderator would cover it...
                              > >
                              > > > > I'd complain to the owner if I were you...... ;o)
                              > >
                              >
                            • Brian
                              Not when they are trying to get rid of 40K of us..... Brian
                              Message 14 of 17 , Jan 2, 2007
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                                Not when they are trying to get rid of 40K of us.....

                                Brian

                                On 1/2/07, Jason Boyle <c4jc88@...> wrote:
                                > nah it is hard to fire government employees.. oh wait your a white
                                > male, never mind.
                                >
                                > jason
                                >
                                >
                              • Jason Boyle
                                Yikes! That makes no sense... we are at war. You can always lateral to a better service. :) Jason
                                Message 15 of 17 , Jan 2, 2007
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                                  Yikes! That makes no sense... we are at war. You can always lateral
                                  to a better service. :)

                                  Jason

                                  --- In backpackgeartesters@yahoogroups.com, Brian <tannehillclan@...>
                                  wrote:
                                  >
                                  > Not when they are trying to get rid of 40K of us.....
                                  >
                                  > Brian
                                  >
                                  > On 1/2/07, Jason Boyle <c4jc88@...> wrote:
                                  > > nah it is hard to fire government employees.. oh wait your a white
                                  > > male, never mind.
                                  > >
                                  > > jason
                                  > >
                                  > >
                                  >
                                • jetriple@rockwellcollins.com
                                  The 4th tester for the PT Quad Headlamp was ME... As far as I know, however, we are all on the same schedule... except that the time period between the Initial
                                  Message 16 of 17 , Jan 3, 2007
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                                    The 4th tester for the PT Quad Headlamp was ME...

                                    As far as I know, however, we are all on the same schedule... except that
                                    the time period between the Initial and Field reports is WAY long for those
                                    who received their lamps first.

                                    Jet

                                    backpackgeartesters@yahoogroups.com wrote on 01/01/2007 02:26:49 PM:

                                    > Cheers
                                    > Roger
                                    > PS for Shane: it wasn't Rick, it might be Coy who was picked for the
                                    > fourth spot I think.
                                    >
                                    >
                                  • Brian
                                    Will I get more pay? LOL.... Brian
                                    Message 17 of 17 , Jan 3, 2007
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                                      Will I get more pay? LOL....

                                      Brian

                                      On 1/2/07, Jason Boyle <c4jc88@...> wrote:
                                      > Yikes! That makes no sense... we are at war. You can always lateral
                                      > to a better service. :)
                                      >
                                      > Jason
                                      >
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