Post #1906: Twinkle lights.

Posted on December 6, 2023

 

I am a huge fan of energy-saving lighting.  Even (or perhaps particularly) Christmas lighting.

But one aspect of the transition from energy-hog incandescent lights to modern LED lights has been unsatisfactory.

My wife misses true “twinkle lights”.   Not flashing lights, or chasing lights, or color-changing lights, or lights that appear to drip, or any of that stuff.  Just strings of lights, where each bulb blinks on and off independent of the others.

So this post is about finding energy-efficient twinkle lights.

Turns out, there are plenty of options that provide some semblance of the incandescent twinkle lights of old.  You just have to look.


The resurrection of the twinkle?

In the incandescent world, twinkle lights were easy.  For each bulb, you ran the electricity through a little bimetallic strip.  The heat of the bulb made the strip bend, which then opened the circuit and turned the bulb off.  Once cool, the strip would bend back, completing the circuit, and turning the bulb on again.  (The same principle was used in automobile blinkers and some home thermostats.  Even today, the same technology remains in use in (e.g.) Mr.-Coffee-style coffee makers, where the slight clicking noise you hear as coffee stays warm is a bimetallic disk turning the electricity to the warming pad on and off.)

For the longest while, as the march toward miniature incandescent and then LED bulbs went on, it seemed as if true twinkle lights had been lost.  Any blinking that went on with LED strings was centrally controlled, so they don’t so much twinkle as flash.  Sure, it was showier.  Sure it was eye-catching.  But you lose the soft innocence of hundreds of bulbs, each making up its own random mind as to when to turn on and off.

But it appears there has been something of a twinkle light renaissance.

Yes, Virginia, you can buy twinkle lights again.


Miniature incandescent strings with twinkle.

Source:  Amazon

First up, Amazon offers a string of miniature incandescent bulbs advertised as twinkle lights.  Could it really be this easy?

Alas, no, based on the comments.  In addition to being essentially unreliable, a) the twinkling is controlled by one special bulb in the string and b) near as I can tell, only about one in five bulbs actually twinkles.  The rest stay lit.  A common description is that the lights “barely twinkle”.

The other drawbacks are that these bulbs burn out fairly quickly, including the special bulb that creates the twinkle effect.  I don’t think replacements are available.  So this is something that you buy, fully knowing that it’s going to end up in the trash soon enough.

I remain baffled by the technology, and might want to order one just to tear it apart.  How can one bulb in the string make some of the remaining bulbs twinkle?

I also note that you can buy individual mini-incandescent twinkle bulbs.  If you look closely at the picture, you can see that these appear to use old-school bimetallic-strip technology, just in a tiny package.  Brutally expensive if purchased per the each.  The same manufacturer sells strings of miniature incandescent bulbs, but only 12 out of 100 bulbs twinkle.

One advantage of these bulbs is that they will “twinkle” by turning on and off.  This is unlike the LED twinkle bulbs below, which basically ramp up and ramp down, without a sharp on-off.  Thus, these incandescents twinkle as did the twinkly bulbs of our youth.


Miniature LED strings with twinkle bulbs

Source:  Amazon, but there are much cheaper sets that also have some twinkling bulbs.  Home depot has sets in the $8 range that have a handful (12 or so) twinkling bulbs per string.

There are many brands of these offered, but all of the cheaper ones are much-of-a-muchness.  All of them say twinkle.  At least some of the descriptions make it clear that each individual twinkling bulb works independently of the others.  But, again, reading the comments on Amazon, only a small minority of the bulbs twinkle.  Some, like the ones above, reveal that fact.  Others you only learn it from the comments.

I’m again baffled by the technology.  But this demonstrates that independently-twinkling LED bulbs are a real thing.  It’s just a question of finding somebody selling an all-twinkle light string.

I don’t know whether the part-twinkle norm is driven by technology, esthetics, or economics.  A lot of times, LEDs are wired in series, and you count on the voltage drop across the each LED to keep the entire string from burning out.  Perhaps it’s not possible to fit a 100%-twinkle LED string into the existing miniature light form factor.   Maybe it’s just costly.  And maybe it’s visually overwhelming.

That said, I’ve found one set that clearly states the twinkle ratio is half twinkling bulbs.  And that set is quite pricey.

Source:  Amazon.

And an all-twinkle set is pricier still.  Near as I can tell, based on description and comments, all of the LEDs in this set twinkle independently.

Source:  Amazon.

The upshot of all that is if you’ve got the dough, they’ll sell you the twinkle.  In energy-efficient LEDs.


Individual LED twinkle bulbs for old-style C7 and C9 strings

Source:  Amazon

These appear to tick most of the boxes for me.  Based on the comments, these give very nearly the same effect as old incandescent twinkle bulbs.  (Which can still be found on Amazon).  And videos posted in the comments seem to bear that out.  These pretty much blink on and off, rather than fade in and out.  The only negative comments seem to be that they blink faster than the old incandescent twinkle bulbs did.

That said, I own no C7 or C9 light strings, so I’d have to factor that in.

On the environmental side, these consume about 0.6 watts each.  That’s trivial compared to the same-sized incandescents (at 5 watts each), but still quite a bit of juice, compared to minature LEDs.  I think a string of 100 LEDs takes about 5 watts, while 100 of these would take about 60 watts.

One thing in their favor is that these would make a much more robust light setup.  First, the bulbs are replaceable.  Second, the old C7/C9 strings, designed for high-wattage incandescent bulbs, are built to a far beefier standard that modern LED strings.  In short, this would solve the problem of tossing light sets out every few years after they cease to function.

Note the wires the size of lamp cord for the C7 string above.  So, buy one of those, toss the antique incandescent bulbs, replace with LED twinklers, and never have to buy one of those again.

Oddly, even the strings sold with LED bulbs have that same beefy construction.

 

I suspect that the same factor is at play here as in modern table lamps.  Old lamps, designed for incandescent bulbs, are hugely over-built for handling the electrical load of LED bulbs.  And yet, new table lamps appear to be built to the old standard, I guess under the assumption that somebody might yet screw in an old-fashioned incandescent bulb.


Conclusion

The upshot is that I have many options for twinkle lights.

The most robust option is to buy an old-fashioned C7 light string, with LED bulbs, and change some of the standard LED bulbs for twinkle bulbs.  Those are a bit big for inside use. And use more electricity than is strictly required.  But with lamp-cord sized wiring, and replaceable bulbs, they should last indefinitely.

Alternatively, it looks like I have at least one option for strings of miniature LED lights, all of which twinkle.  Those are a better size for indoor use, and require less electricity.  But they would be of modern construction, with thin wires reflecting the low current draw of LEDs, and with non-replaceable bulbs.  Those are eventual landfill material, absent my willingness to excise dead bulbs and solder in replacements.  And they do not so much twinkle as fade in and out independently.

There is an option for miniature incandescent twinkle lights, but that seems both expensive and largely D-I-Y.  I can find the bulbs, but I can’t find entire strings of incandescent twinkle lights.

For me, full-sized (C7 C9) incandescents are off the table.  Sure, you can still buy twinkle bulbs for those.  But they seem to clock in around five watts each.  That’s a stopper as far as I’m concerned.

I think I’ll leave it up to my wife as to which direction she’d prefer to go, to more nearly re-create the twinkle lights of her youth.


Addendum:  There’s an app for that.

Source:  Amazon.

In the modern world, you can buy strings of app-controlled color-changing LEDs.  Because of course you can.  But in addition to being able to do animated stripes around your Christmas tree, these can be programmed to be twinkle lights.  So I must add these to my twinkle light options.