Half wave Leds

[jer75]

Hi all ,
Ive been offered a load of Half wave M5 LEDs and due to my sons forth coming wedding that I'm half financing I'm not going to be able to get Full rectified LEDs form any of the sellers you all recommend.
I've read that they flicker when in use but how noticeable is this ? Would anyone have or know for a video showing the difference as these lights may be the only way i'm going to be able to afford to do my display this year.
Also would I need "Snubbers" to aid the fade on them ?
Any help gratefully received

Cheers
Jerry

[papap]

I use 45000 LEDs for homedepot. No snubbers. Everyone loves my light show.

[papap]

I use 45000 LEDs for homedepot. No snubbers. Everyone loves my light show.

[SteveMaris]

Most half wave lights fade just fine.
The exception is many of the Martha Stewart lights which have different circuitry involved in the building of the strings.
They have capacitors built in which does not allow them to fade properly.

[Ozemate]

Full Wave V Half Wave Leds (Christmas Lights)



Unlike traditional incandescent lighting technology, LED lights are not constantly on. That is, all LEDs flicker or turn on and off at a very high rate of speed. This is one of the reasons that they are so much more efficient, but it also can cause some undesirable effects in the appearance of the lights. Currently, there are two different types of LED Christmas tree lights on the market: 1) full wave; and 2) half wave.

Full Wave LED Christmas Lights

Full wave technology is not really new to LEDs. However, the majority of LED holiday lights on the market do not utilize full wave technology. "Full wave" is a term that is now being commonly used to describe sets of LED Christmas lights that are fully rectified. Because a single diode produces a current that flows in one direction for only 1/2 of the AC cycle. An LED set which utilizes a rectifier creates a current that flows in the same direction 100% of the time. The visual result is that the LEDs no longer appear to "flicker." Although the LEDs are still actually "flickering" now they are turning on and off at a rate of 120 times per second which is not detectable by the human eye. For most people this is an important feature. The down-side of fully rectified Christmas lights is that they do not last quite as long as non-rectified sets and are not quite as efficient. This is simply because the LEDs are on twice as much as in non-rectified sets. The loss of efficiency and longevity is relatively low considering the average life of a non-rectified set is nearly 100,000 hours.

Non-Rectified LED Christmas tree lights

In contrast, a non-rectified LED light set only has a current flowing 1/2 of the AC cycle. This means that the LED is turning on and off or "flickering" at a rate of 60 times per second. Although this is not easily detectable by the human eye, most people notice some "flickering" effect especially if the light set is moving. Some people are more sensitive to this than others. Those who are sensitive to it find this to be an unattractive feature of LED string lights.

[George Simmons]

Jeff Spooner wrote:

So what is the difference between half wave and full. Does half way come one half the time or half a bright.

Actually, half as bright is just an old decorator's tale... the preponderance of research that I've seen shows half wave lights to be about 63% as bright as their full-wave counterparts. (That is if you can call them counterparts - since they're technically not the same.)

Another variable, according to a thread I saw just a couple weeks back, is elevation and direction. On vertical light string installations, it seems the light travels faster going downhill rather than uphill. That being the case, and since half-wave LEDs are more efficient than full-wave LED's, it stands to reason that you could run half-wave strings pointing up and full wave strings pointing down and they'd both chase at the same rate.

YMMV. Just saying...

[jer75]

Thanks everyone , So I should be fine using these LEDs in my display ?

[Guest guest]

George Simmons wrote:

Jeff Spooner wrote:

So what is the difference between half wave and full. Does half way come one half the time or half a bright.

Actually, half as bright is just an old decorator's tale... the preponderance of research that I've seen shows half wave lights to be about 63% as bright as their full-wave counterparts. (That is if you can call them counterparts - since they're technically not the same.)

Another variable, according to a thread I saw just a couple weeks back, is elevation and direction. On vertical light string installations, it seems the light travels faster going downhill rather than uphill. That being the case, and since half-wave LEDs are more efficient than full-wave LED's, it stands to reason that you could run half-wave strings pointing up and full wave strings pointing down and they'd both chase at the same rate.

YMMV. Just saying...

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Read the following url to learn about the speed of light:
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html

It is not really very long, but an interesting read for those interested in knowing the facts on light speed and other factors that affect it. But if you don't understand physics or have never taken any type of physics class, you may not fully understand the site.

The info listed below is an excerpt taken from the site:

Another assumption on the laws of physics made by the SI definition of the metre is that the theory of relativity is correct. It is a basic postulate of the theory of relativity that the speed of light is constant. This can be broken down into two parts:

• 
  
• The speed of light is independent of the motion of the observer.
  
• The speed of light does not vary with time or place.

To state that the speed of light is independent of the velocity of the observer is very counterintuitive. Some people even refuse to accept this as a logically consistent possibility, but in 1905 Einstein was able to show that it is perfectly consistent if you are prepared to give up assumptions about the absolute nature of space and time.

In 1879 it was thought that light must propagate through a medium in space just as sound propagates through the air and other substances. The two scientists Michelson and Morley set up an experiment to attempt to detect the ether, by observing relative changes in the speed of light as the Earth changed its direction of travel relative to the sun during the year. To their surprise, they failed to detect any change in the speed of light.

Fitzgerald then suggested that this might be because the experimental apparatus contracted as it passed through the ether, in such a way as to countermand the attempt to detect the change in velocity. Lorentz extended this idea to changes in the rates of clocks to ensure complete undetectability of the ether. Einstein then argued that those transformations should be understood as changes of space and time rather than of physical objects, and that the absoluteness of space and time introduced by Newton should be discarded. Just after that, the mathematician Minkowski showed that Einstein's theory of relativity could be understood in terms of a four dimensional non-euclidean geometry that considered space and time as one entity, ever after called spacetime.

[align=center]---------------------------------- end excerpt -----------------------------------[/align]
[align=left]To read and learn more, again, visit this link:[/align]
[align=left]http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html[/align]
[align=left]Another url of interest on the Speed of Light from Nasa:[/align]
[align=left]http://helios.gsfc.nasa.gov/qa_gp_sl.html[/align]
[align=left] [/align]
[align=left] [/align]

[testraub]

Orville needs to know a joke when he sees it.

Tom Straub

[Guest guest]

Orville wrote:

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Orv, I think you are contradicting yourself here, aren't you? Its dependent on personal perception but never changes?

[scubado]

All mine are 1/2 wave and work fine. Some strings do have snubbers on them for better fading. Newer strings seem to have less flicker issues with them.

[George Simmons]

scubado wrote:

Some strings do have snubbers on them for better fading.

Do you notice a difference comparing a string with a snubber to one without?

Since a snubber is basically adding a bit of resistance to the circuit, the electrons that have to pass through that resistor should be slowed a bit compared to those electrons that DON'T have to pass through a resistor.

Is the difference so minimal that the human brain can't perceive it? Or does the extra heat that those resisted electrons pick up speed them up enough to cancel out the slowing effect of the resistor? Seems like more research is needed here...

[bretk]

George Simmons wrote:

Jeff Spooner wrote:

So what is the difference between half wave and full. Does half way come one half the time or half a bright.

Actually, half as bright is just an old decorator's tale... the preponderance of research that I've seen shows half wave lights to be about 63% as bright as their full-wave counterparts. (That is if you can call them counterparts - since they're technically not the same.)

Another variable, according to a thread I saw just a couple weeks back, is elevation and direction. On vertical light string installations, it seems the light travels faster going downhill rather than uphill. That being the case, and since half-wave LEDs are more efficient than full-wave LED's, it stands to reason that you could run half-wave strings pointing up and full wave strings pointing down and they'd both chase at the same rate.

YMMV. Just saying...

Except, of course, on The Dark Side of the Moon! :dude:

[Guest guest]

DonFL wrote:

Orville wrote:

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Orv, I think you are contradicting yourself here, aren't you? Its dependent on personal perception but never changes?

That's NOT a contradiction, it's a fact. The speed of light never changes, it is always the same, it is each persons perception that changes the speed of light as it is viewed. But the actual speed of light is constat and does not vary.

[Guest guest]

testraub wrote:

Orville needs to know a joke when he sees it.

Tom Straub

Tom, I get it, but if you didn't happen to see in my thread about triacs and William jokingly stated that the new S3 Boards had backlit triacs, within 2 minutes someone contacted LOR support with a ticket saying their GEN 3 Controllers did not have this option. Dan posted a statement about it in the thread to make this clear.

So yes, even though it may be a joke to you or myself, SOMEONE is going to take this seriously, so that is why I or someone else may take the time to post sites where one can read and learn the facts about things or Dan will step in and clear up any misconceptions, like the backlit triac issue that William was funning me on due to my EDM request of a backlit display.

But SOMEONE did, in fact, take that quite seriously and opened a support ticket on it.

I know and you know LOR does not sell LED strands, but now you may have someone going to a site that does and asking about how they should mount their LED's to get the best light speed effect out of them or even asking LOR since it is posted on their site.

Just trying to make sure that folks know where they can go to read the facts about some things. Just trying to keep into compliance with Dan's rules here, after all, like stated, some folks DO take these posts to heart and that's when problems start arising sometimes.

Just saying.

[Guest guest]

Orville wrote:

DonFL wrote:

Orville wrote:

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Orv, I think you are contradicting yourself here, aren't you? Its dependent on personal perception but never changes?

That's NOT a contradiction, it's a fact. The speed of light never changes, it is always the same, it is each persons perception that changes the speed of light as it is viewed. But the actual speed of light is constat and does not vary.

Line in red above should read:

But the actual speed of light is constan and does not vary.



{p.s. I do miss that Edit button!}

[Guest guest]

Orville wrote:

Orville wrote:

DonFL wrote:

Orville wrote:

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Orv, I think you are contradicting yourself here, aren't you? Its dependent on personal perception but never changes?

That's NOT a contradiction, it's a fact. The speed of light never changes, it is always the same, it is each persons perception that changes the speed of light as it is viewed. But the actual speed of light is constat and does not vary.

Line in red above should read:

But the actual speed of light is constan and does not vary.



{p.s. I do miss that Edit button!}

DASH IT ALL!

Line was still wrong! Darn keyboard and No Edit button!

Should HAVE READ: But the actual speed of light is constant and does not vary.

[Guest guest]

Orville wrote:

DonFL wrote:

Orville wrote:

The speed of light DOES NOT change, ever! So whomever wrote that thread has no clue as to the speed of light or physics apparently.

The speed at which light travels is actually dependant on each persons personal perception. It does not matter which way the light is pointed, North, South, West, East, Up or Down, Horizontal or Vertical. There are some variables that slow it down, but the speed of light never changes. Not even from the dimmest bulb to the brightest one, each still travels at exactly the same speed.

Orv, I think you are contradicting yourself here, aren't you? Its dependent on personal perception but never changes?

That's NOT a contradiction, it's a fact. The speed of light never changes, it is always the same, it is each persons perception that changes the speed of light as it is viewed. But the actual speed of light is constat and does not vary.

Never mind.

[jer75]

Well I'd just like to say thanks to everyone for their input , I have the LEDs in my first post on their way to me ,I didnt realise that there would be so much discussion about this topic , but I've learnt a bit on the way.
Many thanks , time to start building my new additions

Jerry

[digdeepfundraising]

jerry how many you ordered and are they 110v