[Boatanchors] LED Flashlights Aren't Collector (or Human) Friendly

[Don Buska]

Hi Robert,

I found your problem with reading the marking on the terminal strips 
very interesting under the white LED lamps.  Have you noticed a 
difference between reading these under a fluorescent light bulb vs an 
incandescent light bulb? 

Most white LED's use a phosphor based system and a blue or UV range 
LED.  The phosphor works like that in the fluorescent light bulb and 
converts it to white by what is called a Stokes shift.  Very interesting 
stuff, hi.  One thing to remember is that this technology is continually 
changing with each new generation of LED by each manufacturer.  My guess 
is the LED's in your flash light were emitting more toward the blue end 
of the spectrum.

We too are getting the newer LED traffic light.  I have not noticed the 
"green" issue you talked about, which is really surprising as I am 
Red-Green color blind deficient.  For us up here in snow country we have 
another issue and that is these LED traffic lights produce so little 
heat it doesn't melt off the blowing snow like the old incandescent 
lamps.  So the light can be completely hidden if the snow is wet and 
clinging to the light in a snow storm.  My guess is that will require a 
future addition of a heating element that gets turned on when the snow 
is sensed building up on the lights.  Having the heater on all the time 
would defeat on of the benefits of the LED lamps in the first place.

If you look you might find an LED flash light which is closer to what is 
often referred to as "natural light" or perhaps actually uses an array 
of Red, Green and Blue LED's.  Instead of looking at these early short 
comings as reasons not to use the technology I'd prefer to look at them 
as engineering opportunities to improve and advance the technology in 
the future. 

73

Don N9OO



WA5CAB at cs.com wrote:
> Groups,
>
> There is a big push on by the environmental nuts to replace all 
> incandescandent lamps with something else, often LED's.  Here in Houston they are 
> replacing all of the traffic lamps and school zone lamps with them.  The red's 
> are generally OK.  Visible under most conditions.  The yellows not so much, 
> and the greens so bad that I have gotten in the habit of assuming that if a 
> traffic lamp isn't red, it must be green.  And blowing through it.
>
> But tonight, I discovered a problem with LED lamps that isn't life 
> threatening but is quite aggravating.  To vintage military radio collectors, anyway. 
>  What started it is that for whatever reason, the final maniual on the 
> TS-382(*)/U audio oscillator covers the A, B, D, E and F models but skips the C. 
>  Naturally, I have three C models.  I discovered that I also have a very 
> poor partial copy of an early un-numbered Instruction Book coverering the A 
> and C models.  So I'm trying to add the C to the main TM.  Not pertinent to 
> this tale but as it turns out, the C is more like the A than the B.  And the 
> majority of differences are in component physical location rather than 
> differences in the schematic.  So I'm trying to ID components and edit the photos 
> of the A model to match the C model.  As in most military sets (and very few 
> civilian ones), the component circuit symbol designators are stenciled on 
> the chassis or on the terminal boards.  The ones on the chassis are no real 
> problem.  But the ones on the dark brown terminal boards, which are also 
> coated in MFP varnish, I found I just couldn't read using the lighting in the 
> shack so I got out both of the small LED flashlights I've been keeping on the 
> bench since receiving them as freebies with equipment I've bought this year. 
>  I got out some Q-tips and water and washed down the boards and was able to 
> read a couple, but with difficulty.  Then I went in the machine shop part 
> of the shack and got the small incandescent MagLite I still have and shined 
> it on one of the stenciled designators.  It was clearly legible as C109.  
> Back to the LED lamp and I could barely make out the 9 through the blue-white 
> glare, but the rest was invisible.
>
> The two LED lamps are now in the S-can (I salvaged the AA batteries).
>
> Robert Downs - Houston
> wa5cab dot com (Web Store)
> MVPA 9480
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