HDS Action Light

I have ordered one of the new HDS Action Lights, the one with the two d-cell waist mounted batts. I am an avid caver and this will be my primary light source. I have read up on the action light numerous times at the website and know that without a doubt this is by far the most sturdy light EVER made! It was made specifically for caving, which happens to be the most destructable testfield for any equipment. I would like to hear from anybody who owns an action light. i'm concerned about the white light output of led's. a fellow caver bought one of the princeton tech MATRIX headlamps with 3 leds and used it on a caving trip and HATED the bluish white light output of leds. said it almost made him sick at his stomach. Does the action light with its high cost have a whiter light output than the MATRIX? I sure hope so. Thanks, Kev

I've been trying to get an all-in-one model for the better part of a year! Did you order yours direct from HDS?

DaveH

Kevin,
If you check the HDS site they have some color shots taken with the lamp - they are proud of the good color temperature they claim the lamp puts out..It looks pretty white to me..
I have the single D cell model, the battery seperate from lamp via wire. I have a helmet configuration wire (short) and longer wire for wearing the battery on the belt. I use an alkaline cell intead of the lithium cell, and it seems to work ok...someone left it on for a day set on low (thought they had turned it off I guess) and now the lowest light level setting doesn't light, but the two higher settings still work fine. (note that this is how the lamp is designed to work, explained at HDS site - has to do with lower voltage of the alkaline cell I am using as it runs down..)


<FONT COLOR="#000000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Ted on 11-08-2000 at 03:53 PM</font>

Huh? I thought it is supposed to work exactly opposite, that is automatically DIM the light as the battery loses power.

"There comes a time in every battery's life
when there is only a little power remaining and it is time to give up on the constant amount of light and go for time. We have mplemented our exclusive SlowDieTM circuitry to detect this condition and to slowly dim the light, no matter what setting the light is on. "

DaveH

I don't know the exact circutry the HDS uses, but here is my theory. Lets say the lithium battery supplies 3v, now on a low seting that turns in to 3v to the led's, just lighting them dimmly. Then in high mode it might supply 6.0v using some sort of step up.

Now if you start with 1.5 from a single D cell, on low you are only sending the LEDs 1.5v, not enough to light them. Then you turn it to high and it changes the 1.5 in to 3.0 which does light the LED's at an OK level.

This is just my best guess based on what the light does (from Ted) and what I have read about it.

Brock

Yes, without checking back to the HDS site, Brock sounds right to me. That's why HDS doesn't recommend alkaline cells. But the lithiums they do recommend are $20 each...You know what, I'm going to turn on the HDS and leave it on, just to see how long it burns with the single (slightly depleted) alkaline D cell...the sacrifices made for science..any suggestions on whether I should burn it on medium or high? (The default setting shall be medium.. :>)
11-11-2000, Follow-up: at 7 Am it was still putting out light..around 8 or 9 am the bulbs were
still lit, but dim. just glowing really - which would be useful in a pitch-black situation - I should have taken the light here with me to see how much longer they would glow for.. Well if they are still lit when I get home, I'll let you know. So thats about 36 hours of light at least, and AFTER, remember, the D alkaline wouldn't light the HDS on the 'low' setting. Interesting point; I turned the light off a couple of times during the test, and then it would not switch back on immediately, evidently it took a few seconds for the battery voltage to rise high enough above a certain threshold voltage before the light would take the 'order' to turn on, then it would blink back on - by itself if left in the on position in 'med' or 'hi' setting...sounds a little confusing, I'm going to read the HDS literature again now...hope this helped... something...
11-12-2000 I had turned the lamp off all day. It lit brightly when turned it on again around 3pm yesterday afternoon, it shined fairly brightly all night again, was still going at 10 AM - another 18 hours of life.. interesting how the alkalines life can be stretched many times by intermittant use.....
11-14-2000 still going! all day and all night, at a steady, bright glow, lights the room...
11-15-2000 still glowing as of 10:30 this AM, but dimmer. so I turned it off..will see if days rest lets it glow brightly all night again...interestingly,when I turned it off, it didn't go back on again, but I think it will after a rest!
11-16-2000 turned on 4pm apx. burned all night, dim this morning, switched off. Bet it's good for at least another night..
11-17-2000 ....sound taps, it was out in the morning.. I turned it to the off position..I'll bet it will shine all night again tonight, though..so I will end this impromptu test here - I didn't think the HDS would get so much light out the single alkaline D.. ]
11-19-2000 still shines brightly after a days rest, but not all night (only the shadow knows when it blinks out at night!)-- here is some info from the HDS site http://www.hdssystems.com that may help explain about the slow-die and forever circuitry - one works on high setting, the other on low:
SlowDieTM Circuitry High power settings dim slowly as battery dies.
FOREVER ModeTM Hours of light from nearly dead batteries on Low setting
Beam Pattern Optimized for best night vision
Beam Angle 1,Ê3ÊandÊ6Êf-stops 20¡/40¡/80¡
Color Temperature 6500¡K
Color Rendering Index 85 - superior color rendering
Waterproof 100m (328ft)




<FONT COLOR="#000000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Ted on 11-19-2000 at 11:57 AM</font>

hi Ted,
just a note so that the date will change in the 'last reply' column and people will know you have made additions to your last post about the HDS lamp (above) - it's been shining 4 or 5 days now, off and on, with the used alkaline d-cell? pretty good!
..not very scientific, but verrrry interesting!...keep up the good work!
--Afan



<FONT COLOR="#000000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Ted on 11-15-2000 at 03:36 PM</font>

A letter from Henry of HDS explaining single alkaline D phenomenon with HDS light:

Ted,

The battery contacts are designed to mate to the special shape of the
lithium battery - specifically, the negative end of the battery has a
special shape and the battery contact matches it. A regular alkaline
battery has a flat shape that will bridge over the gap into which the
lithium battery was designed to fit. The alkaline battery -may-
contact the battery side of the negative contact which is connected
but this will depend on the brand of battery. If electrical contact
is made, you still have the problem that the battery is effectively
1/16" longer since the battery no long fits into the depression and
so the battery cap will not screw down all the way.

But, if we assume the brand of battery you are using makes contact
and you don't screw the battery cap down fully (leaving a 1/16" gap),
the medium setting will work. The low setting bypasses the power
supply, so it will not work because of the low battery voltage. The
medium setting uses the power supply and is within the startup
voltage of the power supply - 1.1V for startup, but it will run down
to less than 0.7V - the power supply is quite stable under these
conditions and the light output just slowly fades as the voltage
drops. The high setting thinks the battery is dying and thus forces
itself back to the medium setting to conserve power. Thus you end up
with two off positions and two medium positions.

Early on in the development cycle we were going to document this but
then we thought better of it due to the liability issues and the high
probability of customer complaints that could result. If people ask
we are happy to tell them, but we do not recommend doing so unless it
is the only way out. It is good to know in case of emergency but
otherwise you should not do it.

The above applies to the light you have. The new power supply (V2) I
am working on will not have these limitations - all settings go
through the power supply and the high settings do not have the
limiting circuitry - they are only limited by the batteries ability
to provide power. Realistically, the High and Overdrive settings
will still not work with a single alkaline battery for any length of
time because a single alkaline battery cannot provide enough power.

I hope that answers your question. If not, let me know.

Henry.