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571  Community / Bar Sport / Don't know who Cree is?..... on: October 30, 2013, 08:06:05 pm
Here's Cree's time line attached..

I think it's pretty outstanding that in 2013 they've reached 276 lm/w. if you consider  a regular edison incan bulb is only  a couple of lumens per watt!

or roughly around 800 lumens for 3 watts of power  (so 1 lithium battery 4.2v 3amp/h gives 0.7amp/h draw) roughly up to 4 hours of very very bright light on a single 18650 lithium battery  smiley-eek-blue smiley-eek-blue smiley-eek-blue

luminous efficacy compares a broader array of light sources to one another.
Type  Overall luminous efficiency    Overall luminous efficacy (lm/W)
40 W tungsten incandescent            1.9%    12.6[1]
60 W tungsten incandescent              2.1%    14.5[1]
100 W tungsten incandescent             2.6%    17.5[1]
glass halogen    2.3%    16
quartz halogen    3.5%    24
high-temperature incandescent    5.1%    35[44]
ideal black-body radiator at 4000 K (or a class K star like Arcturus)    7.0%    47.5
ideal black-body radiator at 7000 K (or a class F star like Procyon)    14%    95
ideal monochromatic 555 nm (green) source    100%    683[45]

572  Using Arduino / LEDs and Multiplexing / Re: 10 Watt high power LEDs. on: October 30, 2013, 07:42:30 pm
If you are using current limiting resistors, then you will not damage the  LEDs. However the assessment that with PWM you can perhaps reduce average current but not peak current is still correct.

I could not care less about controlling the current via PWM, as far as i'm concerned i'm trying to get as much current draw from PWM as possible.... I have everything heatsinked and works great, except I used a bad 74hc chip (never checked it first before soldering) the other half my circuit board works great smiley-sad
573  Using Arduino / LEDs and Multiplexing / Re: Drivers meanwell LDD....hum on: October 30, 2013, 07:17:04 pm
Due to the high levels of current involved, i'm wondering if it's the wires ....

The strong magnetic fields may repell  / attract causing a frequency which grts converted to mechanical energy and we hear it... swich it on and firmly grip the cables see if it stops....
574  Community / Bar Sport / Re: VOID ON WARRANTY!!!! why? You modified it... on: October 30, 2013, 07:10:56 pm
"Some random firmware"


No... eg, flashing an official samsung stock rom, will void it!
575  Community / Bar Sport / Re: VOID ON WARRANTY!!!! why? You modified it... on: October 30, 2013, 07:17:20 am
You of course could flash a rom to a mobile device and then overclock it, you could also do the same thing via a BIOS on a computer, does that void your warranty?

So why would flashing an Iphone or Galaxy cause a Void on Warranty?
576  Community / Bar Sport / Re: VOID ON WARRANTY!!!! why? You modified it... on: October 30, 2013, 02:50:39 am
If you can prove a way to psychically modify hardware then James Randi will award you $1,000,000.

I really doubt that Toyota would refuse mandated brake work over a changed music system.

Question is, did that firmware update come with a warranty-voiding agreement that you might have clicked your way right through?

Did you read anything except the last few sentences?
577  Community / Bar Sport / VOID ON WARRANTY!!!! why? You modified it... on: October 30, 2013, 12:11:31 am
It's a bit of a rant, I guess....

But I think it's about time, ALL electronic manufacturers from Sony and Samsung and Apple to Intel, Logitech, basically all of them should have new Guidelines on what really voids "WARRANTY"

For example,  Several months back I flashed my firmware, the device worked better and faster than it ever did before! But sadly, yesterday for no reason at all the screen stopped working, the device worked fine, plug it into a TV and it worked, so obviously it was purely a hardware fault.

Why should a person have to suffer for something completely out of their control?...  all because they  modified their device be a phone, tablet or TV.....  

So unless you "bricked" the device or opened it up or psychically modified it....  any naturally occurring problems due to bad batches should be covered by the warranty, and it is, providing you've not flashed it's firmware in which case tough look.

In which case, someone with an evil mind could one day work out and find some kind of new exploit and have this trojan/virus spread just laying wait for a certain day and kaboom,  using some kind of root exploit, then modifiy it's own firmware by copying the contents and or rebooting or with elevated privileges....

Could void million's of devices in a single day....  

So Anyway, Warranty rules need to be changed to something along the lines of "would it have broken anyway eg faulty batch of LCD screens" or did you cause it because you don't know what you're doing?... then you pay the price, if it's the manufacturers fault then it should be covered regardless... if the engineers have to "unbrick it" or have to do anything to correct the end users problem other than the faulty hardware....

Warranty should cover it!

We recalled all the cars between 2012 April and 2013 Jan it turns out the brakes are potentially life threatening and should be serviced and replaced asap.

- Oh... ok,

Sir... yes?.... Is this your MP3/Mp4 video player and not the one that came as standard?...

Why yes...

Oh, did i say free?... that will be  $3,000 for voiding the warranty.

Is that how it works? I'll have to check now....

578  Using Arduino / General Electronics / Re: To clarify about polyfuses on: October 29, 2013, 03:44:09 pm
It also depends on where/what you shorted...

The 5v to GND for example, would only be lethal if you did that with a pin out/in from the micri.

Problem with poly fuses is that most are rated > 500ma which is plenty to kill your arduino before it stops passing current!
579  Using Arduino / General Electronics / Re: Who can identify Chinese led color names please? on: October 29, 2013, 06:08:19 am
Get a resistor, chop one lead off leaving enough of a lead to connect a croc clip, with the other crock on negative/positive use the cut iff lead so you end up with 2 legs to probe the smt led with.
580  Using Arduino / General Electronics / Re: Splitting 5v and ground wires on: October 28, 2013, 03:03:16 am
Then it'll be fine ....
581  Using Arduino / General Electronics / Re: Splitting 5v and ground wires on: October 28, 2013, 02:54:42 am
Only one thing concerns me, total current load...
582  Using Arduino / General Electronics / Re: A 555 FM Modulator! on: October 28, 2013, 01:05:32 am
I must correct my post, it's not a Transmitter, it's just the FM modulation circuit for a Transmitter.
583  Using Arduino / General Electronics / A 555 FM A 555 FM Modulator! on: October 27, 2013, 11:36:25 pm

Impressive no?...
584  Using Arduino / Programming Questions / Re: Trying to make accurate 20 KHz clock, not getting there on: October 27, 2013, 09:38:30 pm
Is there a possible hardware solution? problem would be getting the right divide by combo to get the 20KHz clock, then two trimming capacitors to adjust the frequency.

CD4060 and a Crystal that is divisible into 20khz....

4040, 4020, etc etc (for quick reference)

Anyway only as an alternative option (or use  Flipflops and a gate oscillator (if you have them on hand).... )
585  Using Arduino / LEDs and Multiplexing / Re: 10 Watt high power LEDs. on: October 27, 2013, 08:30:06 pm
You CANNOT lower the current draw using PWM. You limit the overall energy going into the LED, however, if the current exceeds that of the LEDs spec you may have already shortened the lifetime of the LEDs.

You are kidding......... right?

You CAN lower the current draw via pwm (i do so all the time)

May have damaged?.. i wish i could get the current draw high enough to damage them due the pwm signal!

No, they are not kidding smiley

Unless you are using a Constant Current Driver with a PWM dimming capability, you can only reduce the average current not the peak current via PWM. If the peak current exceeds the recommended maximum of the LED then you will do some damage.

ughhhhh... for god sake! I have a limiting resistor on the base of each transistor!

- I was being sarcastic.. you ARE kidding.

Even IF it "stopped" and got a constant hit with 5v....  the MAX current draw is 400ma (yes I've DONE IT, i have it wired up that way)

Now, stop with the bs please, I know what i'm doing here.....
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