It's that time of year again, the time where we embrace the meaning of the holidays by
relentlessly spending our money at various shrines to consumerism around the world, and
covering our homes in a superfluous amount of lights.
I'm not so much a fan of the former, but I do like lights.
And in this video, I'll be showing you my favorite kind.
This is the part where you say, "This isn't what I thought the next video was going to
be about!", and you're right.
I just came back from a family trip and still have to finish that one up.
For now, though, I want to show you a special kind of light.
These lights seem to be fairly uncommon, which is a shame because the effect they produce
is in my opinion unparalleled.
As you shall soon see.
First a few qualifiers.
If I were to refer to these as Hmm hmm lights, I'd annoy a particular set of people.
And if I referred to them as hmm hm hm lights I'd annoy the opposite particular set of
people.
So I'll take the British approach and refer to these as Fairy Lights.
Now you're both annoyed.
This video will focus mainly on incandescent fairy lights because the sets I'm talking
about fall under that category.
So first, some general info.
Note that this is from an American perspective where fairy lights run at 120 volts.
Incandescent fairy lights of this style tend to be constructed as cheaply as possible.
The wiring is done point-to-point, with the lamp holders simply being a plastic tube thing
with the wires just sorta poking up through the bottom and being held to the sides.
The lamps are equally primitive.
Just a glass envelope with a tiny filament suspended between two support wires that go
straight out the bottom of the glass.
A removable plastic base holds the glass with the wires bent up the sides, and it lines
up with the lamp holder, which presses the wires of the bulb into the wires at the sides
of the base.
A set of 100 lights is typically made of two series circuits of 50 lights each, with the
lights running at about 2.4 volts.
If you remove a light from the string, that opens the circuit, and half the strand goes
out.
This is the cause of much frustration, let me tell you.
But, to prevent a burnt out bulb from opening the circuit and thus killing half the string,
the bulbs are constructed with a clever little feature.
At the base of the bulb, wrapped around the support wires, is a little wire loop.
This wire is coated with a weak insulator that will prevent current from flowing through
it at the normally low operational voltage.
But if the filament breaks, the full 120 volts is briefly present at the lamp because none
of the other lamps are receiving current and dropping the voltage down.
The insulation around the wire loop will usually break down with such a high voltage, which
turns it into a shunt, thus shorting out the lamp and continuing the circuit.
This is known as an antifuse, and I said the insulation usually breaks down because we
have all had a set of lights that just refuses to work for no apparent reason, and this is
a possible culprit.
That's what light repair devices are used for--by detecting voltage at each of the lamps,
you can travel along the string to find out which light is the last to receive voltage,
and thus which one is likely the cause of a fault.
As an unfortunate side-effect of this feature, each shorted lamp increases the voltage across
the remaining lamps.
With 49 operational lamps instead of fifty, each lamp now gets about 2.45 volts.
They're rated at 2.5 volts, at least in these sets, so one or two burnt out lights
won't be too harmful.
But with only 45 lights working, each remaining light gets 2.66 volts.
With 40 operational lamps, the rest get a whole 3 volts.
Each burnt out light makes the rest work harder, and thus increases the likelihood of future
lamp failures.
Eventually, the set will experience a rapid cascade failure of all the lamps, turning
the whole string into a short circuit, and the fuse in the plug will blow.
It's for this reason that you should replace a burnt out lamp as soon as possible in a
string of miniature fairy lights.
So, now that you understand the operation of fairy lights a little more, let's get
to the subject of this video.
Most conventional strands of lights come with a couple of flasher bulbs, identified by a
red tip.
These contain a bimetallic strip that reacts to the heat from the filament, causing it
to bend.
After a certain amount of time, the bimetallic strip bends sufficiently to break the circuit.
Once it cools down, the circuit will be reconnected, and the filament will re-light, which reheats
the bimetallic strip, and it goes out again.
This repeats over and over and over again.
When you replace any lamp with one of these suckers, it will cause half of the light strand
to flash because it will break the entire circuit once the bimetallic strip has warmed
up, and will reconnect it once it cools.
I've always found this to be a rather dumb looking effect, and I think most people agree
because these flasher bulbs seem almost never to be used.
But, there are some strands of lights that use a different kind of flasher bulb, and
use many of them.
These seem to be sold as "twinkling" lights, and their approach is completely different.
These are the subject of this video, and I really really like them.
These strands use many flashers, typically every fifth light, and these flashers don't
break the circuit when the bimetallic stip bends.
Instead, they short out when the strip bends.
This does two things.
First, the current bypasses the filament as it takes the path of least resistance, and
the bulb goes out.
But, it also increases the voltage to the rest of the strand.
When you first power one of these sets up, the entire light strand is illuminated.
But as the flashers heat up, they start to randomly go in and out.
This is a great effect on its own, but because they short themselves out when they're not
lit, they slightly affect the brightness of the entire strand.
This is most easily seen with a new set still wrapped together, because this entire bundle
has no flashers among it.
Notice how it shimmers.
This happens because the voltage across these lamps is constantly changing as the flashers
do their thing.
Yet another great side effect of the way these work is a gradual transition in brightness
with each flasher.
Normally, flasher bulbs produce a very sudden on-off effect since the entire strand goes
on and off at once.
Because the strand as a whole sees 120 volts when it first receives power, the filaments
nearly instantly achieve full brightness.
The voltage between them doesn't drop to 2.4 volts until they're all hot, as the
resistance of an incandescent lamp is about 15 times greater when it's hot compared
to when it's cold.
But since the lamps in a twinkling set only see between 2.4 and 3 volts across them as
they twinkle, they don't have 120 volts to get them started, so they don't suddenly
turn on and off like a conventional set.
See, when you apply just 2.4 volts to a normal bulb, it lights up very slowly compared to
just plugging a set into the wall, because the lower voltage will pass less initial current
through the filament, and thus heat it more slowly.
This creates a more gradual turn-on for the flashers which I find very nice.
Now, you might ask, why am I making this video?
The short answer is, I find these sets of fairy lights to be nothing short of delightful.
They're a nice enhancement to a static display without being annoying, and their randomness
is appealing.
Though animated LED based strands are available, they don't come close to these in my opinion.
And, these sets are harder and harder to find.
In fact, I don't think many people realize they exist.
I rarely see people using them.
The only place in my area that seems to reliably stock them every year is Menards.
Now if you're not an American midwesterner you probably don't know Menards, but they're
a local chain of hardware stores, essentially a larger, quite a bit more eccentric version
of the Home Depot or Lowes, complete with a banjo-filled jingle.
♪ Save Big Money at Menards! ♪
ACE hardware also had a small number of sets for sale, but clearly they don't sell too
well as they're kind of left alone among dozens of other offerings.
The Home Depot doesn't appear to sell them, and neither does Walmart.
I don't have a Lowes near me, otherwise I'd have checked.
If anyone knows of other places you can find these, please let us know in the comments.
It may be that they're uncommon because the rest of the lights are designed to tolerate
the increased voltage the flashers let through.
They aren't your standard 2.4 volt bulbs, in fact they're 2.9 volts,
a somewhat rare rating.
This high voltage rating allows them to spend most of their existence being underrun; they
will see their rated voltage only in the rare instance that nine or more flashers along the 50 light
circuit are currently in the off state, which virtually never happens with 10 total flashers.
On average they only see 2.66 volts.
And while we're on the subject of fairy lights, allow me to express a few grievances.
This, I'm sure, is more preference than anything, but there's only one retailer
near me, that's ACE hardware, that sells what I consider to be the "correct" color
combination of simply Yellow, Red, Green, and Blue for multi-colored light strands.
Nearly everyone else uses orange instead of yellow, and adds purple or pink.
Sometimes there's even a cyanish blue in there.
I'm most bothered by the replacement of yellow with orange because yellow is a very
bright color and provides contrast from the others.
Orange is too dark and similar to red.
But that's just my humble opinion.
Also, I really don't care for most multicolored LED fairy lights offered today, largely because
of the way they are implemented.
Perhaps I'm out of touch, but I am not a fan of the monochromatic blue LEDs used in them.
They produce a visual effect for me of a fuzzy halo and are almost hard to focus me eyes on.
In fact, I find all of the colors but red to be a bit jarring precisely because they
are monochromatic.
I'd like to see a set of multicolored LED lights made with entirely warm white LEDs
but with tinted diffusers just like in the good old days.
I think these would be easier on the eyes.
In fact, that gives me an idea…
I'm gonna do some experimentation and report back in another video.
In general I think LED fairy lights have gotten very good lately, and the warm white color
is becoming better every year, plus I think applications like icicle lights or snowflake
type things are a good application for cool white LEDs.
I particularly like the fact that since they use so little power you can string many sets
together without worrying about capacity.
But I don't like the fact that they're constructed just like incandescents sets.
In fact, I purchased this set of lights just to confirm my suspicions, and though I don't
want to suppose this is convention, I find it rather funny that these are just regular
LEDs with their pins shoved down a regular lamp holder and bent up the sides, with the
rest of the light strand design being essentially identical to an incandescent one, aside from
this little doodad which I'm assuming is a diode and capacitor to limit current.
I know other sets use fancier diffusers with other shapes, but the sockets are usually pretty similar
But on that note, it seems nearly every LED set I've encountered is only half-wave rectified
with no smoothing at all, which makes them flicker like mad.
Spin them around and you can see that they're lit perhaps only 10% of the time, owing to
them only being lit at the very peak of the positive cycle.
Anyway, I'm all for energy efficient lighting as anyone who follows this channel knows,
but I haven't seen an LED set that can duplicate this twinkling effect so well.
Most of them are animated strings like this, but they don't address each bulb individually
so it's an unsubtle and predictable effect.
I have seen some applications of prelit figurines with a small percentage of LEDs that do twinkle,
but if memory serves the individual LEDs flashed at a steady rate.
They weren't all the same flashing rate, so they drifted apart from one another, but
there was no randomness in each one.
Also the rest of the lights were unaffected.
I'm afraid I'll have to just be a fuddy duddy a little longer and keep buying a few
backup sets of these each year.
I've got 5 extra now.
And no, I don't have a problem.
Thanks for watching, and I hope you found this video interesting.
Like I said, I want these lights to survive and I want more people to know about them.
I'll leave you a view of the lights on my balcony so you can enjoy them.
If you're new to this channel and like what you saw, please consider subscribing!
Of course, thank you to all of my Patreon supporters for keeping this channel possible.
You really make all the difference.
You can support this channel through the link that will appear shortly on your screen, or
by visiting the link down below.
Thank you for your consideration, and I'll see you next time.
(Strained) Oh, god.
Those were very hot.
For more infomation >> Christ the Healer Episode 157: But Now - Duration: 28:30. 
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