Very minimalist light sensor with flicker issue

Dave sent this for our exploration. It's a dusk sensor that was built into a wall mounting bulkhead light, but the very minimist circuitry means that at the transition from day to dusk (and dawn) the light will flicker.
This module was probably intended for tungsten bulbs, but has survived the transition to LED versions. The stability issue is purely down to the simplicity of the circuitry and the lack of significant hysteresis at the switching point. There's a high probability that it's sensitive to light leakage from the bulb it's controlling.
Given that it seems to switch near the zero crossing point, it shouldn't harm most lamps, but it's still not an ideal way to control them.
The fix is to swap it out for a three wire version that has a permanent supply so it can use more sophisticated circuitry.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- www.bigclive.c...
This also keeps the channel independent of KZbin's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators

[@jamesvandamme7786]

"Positive feedback is the cure for comparator flicker" said that ancient Greek philosopher, Hysteresis.

[@DavidVR2]

Clive, It was me that sent you the sensor to investigate, thank you for the clear explanation of how it works and why it flickered so badly. The replacement three wire dusk sensor that I purchased from Amazon is about the same physical size and has a built in 12 second switching delay, no further problems since installation. Thank you again!👍

[@theagileaardvark]

I think enough people have misread the title that Clive should try to make a minimalist duck sensor now. :D

[@ZacabebOTG]

The question remains what that sensor is; a minimalist sensor of ducks or a sensor of minimalist ducks?

[@mxslick50]

My first read of the title with my blurry morning eyes came up with a different 'D" word, and it wasn't duck.😮

[@theagileaardvark]

@@mxslick50I'd bet Clive already has a sensor for that :D

[@pmpwiz]

@@ZacabebOTG Whichever is easiest, I would presume. 😊

[@twocvbloke]

For some reason, I read the thumbnail as "Minimalist Duck Sensor", and wondered what you were planning on doing at the local duck pond... :P

[@zaraak323i]

I just came here to type that! Not until Clive said "dusk" did I realize my mistake.

[@twocvbloke]

@@zaraak323i Seems quite a few of us have read it wrong going by other comments... :P

[@GlutenEruption]

I read it as "Dust sensor" lol

[@Bob_Bobstien]

Glad I'm not the only one

[@barryhodge2908]

I done exactly the same! 😂

[@smilerbob]

I have had many flicking light (or darkness) sensors. The most amusing installation I have seen was for a light circuit but the sensor was placed within range of the light beam so the light itself was causing the sensor to turn the light off which made it dark enough to turn the light back on which then….you get the idea They ended up placing a plastic shield between the light and sensor rather than move the sensor. It worked for them

[@dogwalker666]

Dusk/Dawn sensors are supposed to operate at 70 lux, They are never calibrated.

[@AssemblerGuy]

My workplace has sold LED panel lights from a Chinese manufacturer for years, and they too has the habit of soldering the ends of multi-core leads which normally go into scew terminals. I constantly clipped off the soldered bit and removed the insulation to reveal non-soldered cores when preparing these for the electricians who installed them at the customers' premises. To manufacturers in China and elsewhere: Multi-core leads have a slight "springy-ness" to them, making for a more reliable connection when they're connected with scew terminals. By putting solder on them, you make them more rigid, and thus more prone to dislodge themselves over the years.

[@Mark1024MAK]

Solder flows very, very slowly under pressure, so if a soldered stranded copper wire is clamped in a screw terminal, eventually you will end up with a poor connection. And if there is a significant current flow and enough voltage, it may arc nicely, overheat and burn the connector...

[@W4BIN]

The reason for the 47. µFd capacitor is to provide a delay that minimizes flicker, too bad he didn't measure it's capacitance. He said it is in a "made to fail" location. Ron W4BIN

[@davidkane4300]

Clive, try this with a dimmable LED bulb! It may create a nice effect where it proportionally increases light output as it gets darker outside, and proportionally dimmer as it gets brighter outside.

[@eDoc2020]

That's what I was thinking, the circuit is very similar to a traditional TRIAC dimmer. The downside is the rectified design makes it much more likely it will trigger on the next cycle, causing flicker. If the same circuit was made with a TRIAC instead of rectifier+SCR it would probably dim properly.

[@davidkane4300]

@@eDoc2020 yeah, I'm curious on how they'll react. I know I've put a traditional dimmer on a circuit with fluorescent lights that had traditional ballasts with starters. The random flickery light show was fun!

[@eDoc2020]

@@davidkane4300 I've actually had fairly good results using a traditional fluorescent light on a TRIAC dimmer. The hard part was getting it started, but then I could probably go down to 50% brightness before it started acting up.

[@patomahony9747]

Thank you Clive. Really nice to see the workings of devices like these. Was surprised you did not feature a “hack” of some kind to rectify the “shimmer” While I know there will be plenty of videos on line of various diy dusk sensors. I would really like to see your design of one of these that will work on say 12v/5v or 3v dc led projects , where the ldr is fitted in a tiny hole/mounting on likes of led candles or other items. Some years ago I came across those poundland led strip lights you featured. the dusk sensor modules in those work on ,iirc 5v to 15v and rescued some that were being “dumped “ because customers had opened them etc.

[@BigClive]

It would be complex to add hysteresis to such a simple design.

[@mySeaPrince_]

I would like a 12 volt DC light sensor.. operating voltage 10v to 16v ... I have solar panels. Also lower and higher voltages 1.2, 3, 5, 24 & 48 should cover most.. I was wondering if a zener and a capacitor but no idea which... Electoboom might employ a 12uF 💥 capacitor ⚡

[@kenaston4220]

You could try inserting a resistor between the LDR and the gate and maybe at the same time, increasing the value of the capacitor. Its not hysteresis but it would delay the turn on / turn off and maybe stop the flickering?

[@davelowets]

​@@kenaston4220it wouldn't...

[@GothBoyUK]

That circuit brought back memories of Electronics class back in the 90s. It felt like we were doing magic at 12 years old. 😂

[@KeritechElectronics]

As simple as it gets... Not even a comparator!

[@zh84]

Wouldn't this be an ideal use of a Schmitt trigger?

[@KeritechElectronics]

@@zh84 it should, or at least a quick-charge-slow-discharge RC + diode circuit feeding the thyristor gate.

[@mattmoreira210]

Or (heaven forbid!) a trigger pulse generator of some description.

[@dave_s_hemmings]

I’m either over tired or in need of a more comprehensive eye test but for a passing moment I thought the title of this video was Minimalist Duck Sensor 🙃

[@twocvbloke]

Wasn't just me then... :P

[@smilerbob]

🦆 🦆

[@robegatt]

Made with an LDR ... Leaving Duck Reactor

[@brabhamfreaman166]

@@robegattLost Duck Response?

[@robegatt]

@@brabhamfreaman166Lost Duck Revelator 😁

[@Acamperfull]

The Chinese testunit seems to have an on-off switch type that could have a neon light built-in which you could use as an indicator that it is turned on?

[@samuelfellows6923]

illuminated switch

[@davidkane4300]

I thought that too... If there isn't a lamp in that switch, it seems to be a standard size that can be easily changed out with one that has a lamp.

[@JoFreddieRevDr]

I have a similar issue at dusk with "5000w solar LED street light" I have which you featured in the video posted on 22 Oct 2023, it work fine once it is dark.

[@phonotical]

Suggests it isn't for led bulbs but for incandescent

[@tncorgi92]

I think that's part of the problem with mine, it's never really worked properly with LED floods

[@jennyjansen754]

I was wondering that also. However it would be more efficient to leave LEDs on 24-7 than use incandescents.

[@davidkane4300]

My thoughts exactly! Back when I was an electrician, CFLs were popular (and LEDs just starting to come to market), but the majority of photocells were still designed for incandescent lamps. When a CFL or LED was installed, it would flicker at dusk and dawn until it was sufficiently dark or light enough to fully be in or off (and if I remember correctly, they were never fully "off", which wasn't an issue with an incandescent lamp).

[@melkiorwiseman5234]

I think that all dusk sensors which don't use built-in hysteresis are going to have problems with flickering when in an edge state. I used a circuit from a web site in order to make a simple solar battery charger to operate some LED lights after dark. It's pretty sharp in its response to dusk (goes from fully off to fully on in roughly 1 minute) but it doesn't instantly turn the lights on or off. It's a gradual transition.

[@LDuncanKelly]

Soon as you mentioned flicker, I knew what was going on... Typical economy photoeye using a CdS cell and triac or scr instead of an old school thermal relay with its inherent hysteresis - no problem with tungsten incandescents as it mostly just ramps up in brightness but flickers badly or can cause premature failure with led and discharge (HPS/MV/MH or florescent) lamps as the drivers/ballasts usually aren't designed for large variations in the supply...

[@davidkane4300]

I also noticed the LED bulb Clive used is non-dimmable... I wonder what would occur with a dimmable LED? Maybe a nice effect where the light output is proportional to the darkness level? Like a small amount of light at civil twilight, gradually increasing as nautical and astronomical twilight occurs, then full brightness at night...

[@Ale.K7]

Clive, for the indicator light for the lamp tester, did you check if the switch already has a neon lamp that has not been connected? I have a water heater with a switch like that that din't have a power indicator* and, when I opened it up to change the switch for an illuminated one, I discovered I only needed to add a little bit of cable for the unused neon lamp already on the power switch... *It did have a power indicator, but not a useful one: It has a red/green LED to show if it is heating or not, but the red one (not heating) is directly wired to the mains with a capacitive power supply and will light as long as the heater is plugged in, no matter if the power to the heating element has been cut with the power switch or if the green (heating) part of the LED is on...

[@SeanBZA]

Reminds me of those old National Panasonic light sensors, with a relay coil, with a massive CdS cell on top, bare, that was under the plastic dome. Very simple circuit, 220VAC coil in series with the huge CdS cell, and a single NC contact on the relay arm, with an adjusting bar that was bent during "calibration" so the relay would close the magnetic circuit when the CdS cell was exposed to morning light level, and in the evening, when the cell got high resistance, the calibration to have it release, and thus close the electric contact, was to shade part of the cell. they did tend to flicker and oscillate in the evening, as the stray light would reflect back on the cell, and thus you would have a few cycles of on and off on some evenings, unless the cell was far from the light. Big advantage was that they would survive quartz halogens failing and going near short for a cycle or three, which would blow up lesser relay units. But they would wreak havoc on mercury vapour lamps with those multiple start cycles. However, did have a few where they ran 1kW of mercury vapour, 8 125W tubes around the premises, and the cell way up high, out of the sight of the lamps, and hidden from the lamp spill light. Those were garden lights, with a mix of MV, and a whole lot of 12V 50W dichroic lamps fed with some 500VA transformers, all running off the same daylight. That survived everything, from gardeners putting spades and forks through the cables, lamps getting wet when seals failed and blowing up, and ballasts that went short circuit from waster ingress. I learned how to do scotchcasts a lot there, and migrated all the halogens away from individual transformers to big honking ones in the crawlspace, making fixing wiring easy, no scotchcast on armoured cable, just replaced with regular 1.5mm cable, and new glands, and you can fix it with tape when broken. Also no blowing holes in plants when the cable failed.

[@GilmerJohn]

Most of these have "thermal relays" in which the "coil" just heats a bi-metal contact. When it gets hot , it opens the circuit. Thermal lag solves most problems.

[@SeanBZA]

@@GilmerJohn Yes have seen plenty of those, but the National ones were almost all relay based.

[@T3hBeowulf]

This looks like one of those old-school night light designs from the 80's/90's made for switching on an incadescent bulb when it gets dark. They used to be a Poundland/Dollar Store special. I remember those being so flickery even with an incandescent 7W bulb if used in an area with a window near sundown. They were much better in windowless places where the main room lightswitch gave them a dedicated cutoff point. Cool breakdown!

[@DjResR]

Some cheaper modern ones still use this circuit._

[@ferguscampbell2485]

The last time I saw this circuit was as a cheap dusk censer for incandescent light bulbs. They would smooth out the flicker problems.

[@JoaoFranciscoFigueiredo]

1:15 nasty tingles in the morning, makes you awake better then coffee with cocaine 😅, probably is those LED bulbs not fit dimming made🤷. Thank you, for the schematic

[@NinoJoel]

1:15 while the Original wago connectos are not made for soldered wires they hold it down anyway. I'd guess it was the weaker metal spring inside the fake one.

[@ronsimpson8666]

Now do a video where you 'cure' the flickering. That would rock! ❤️✌️

[@BigClive]

That would require supreme trickery or a complete redesign.

[@beamer.electronics]

I built (for a YT video and my channel) a nightlight using an 8 pin ATTINY chip and a light diode (faster). Using powerful 12VDC car LEDs, I automatically blanked the LEDs just before a true light level was read (you couldn't see the blank pulse). As the LEDs were mounted on the same box - oscillation could occur, I solved that by - once triggered, it would wait for about 10 mins before another sample was taken. No hysteresis involved, I built this so that my physically challenged wife could traverse our hall - circuit still works great after 10 years. It's powered by Gel battery for emergence power outs. Observation: A lot of materials hold onto light - persistence (very short duration).

[@madscientist15808]

What an interesting little sensor. Just for fun, I'm going to build one based on your schematic and try it out with an incandescent bulb to see what happens. I suspect it's just going to work like a dimmer.

[@fyrrydr4g0n]

I think my friend's house had similar dusk sensors in the coach lights, one always flickered until we swapped the lamps for better LED units, bypassed the photocells, and put them on a timer.

[@carlubambi5541]

The cadmium suphide cells are amazing for lighting control

[@clynesnowtail1257]

I had one of these in the fixture by my front door. It did the same thing. I think the intent was they would be used with tungsten lamps and it would work out kinda like a very crude PWM dimming. I bypassed it and installed a fancy light switch that has an almanac and can calculate the dusk/dawn times based on the Lat/Long provided during setup. I hadnt even thought of the electrical noise from the switching. That would've been horrible had I been able to use my HF rig.

[@Echristoffe]

For the WAGO clone problem, indeed the clone doesn’t have the same quality of the real one … But also maybe it has been damaged by using too big wire …

[@andygardiner6526]

or using a wire at all! :-) "Trashy Chinese clone" says it all

[@samuelfellows6923]

Chineseum crap 😠

[@clownhands]

Hey Clive, perhaps consider moving the bench power module’s voltage display to the load side of the switch so you can see if it’s turned on or off

[@BigClive]

I've considered that, but it would mean it went through its power up sequence and display voltage instead of just showing current immediately.

[@HowardLeVert]

Or just fit an illuminated rocker switch.

[@castletown999]

Clive, If you point the sensor at the light it is controlling you have built a nice little oscillator. The 0.47uF cap will set its frequency.

[@cmyanmar13]

I bought real Wago terminals after seeing them on your channel. They've never given me a problem with soldered wires.

[@markmarkofkane8167]

Thanks for not leaving us in the dark!

[@Sierra-Whisky]

1:14 "... to avoid nasty tingles." 😂😂😂

[@rikardogibola1312]

I have this set-up. No problem with filament bulbs.

[@silverback3633]

The flickering is caused by the light you are shining onto the sensor. The LED lights are PWM-modulated and have a duty cycle to save energy.

[@MaleAdaptor]

Clive, great video. I was looking to make a "mains flame effect light bulb" . This circuit gives me a good idea. I was going to use micro controllers and random numbers etc but this simplifies things.

[@tubastuff]

That the thing works with LED lamps at all is a bit surprising. Here in the US, it wasn't uncommon to see "nightlights" using a small 7 watt incandescent connected to a triac and a CdS photocell with a couple of resistors. Those don't work at all with LED lamp replacements, unless a high-value resistor is shunted across the lamp terminals to provide enough current for the circuit to operate.

[@davidkane4300]

Yes, it was a pain when CFLs (and LEDs soon after) were all the rage, but didn't work in existing outdoor fixtures with built-in photocells, so people would go buy a new one and have the same issue. I have been out of the field for over a decade, so I can't say when (or if) they solved this issue, but I do know I've seen newer construction homes with LED array outdoor light fixtures, so maybe they just skipped the replaceable LED bulb market altogether and just sell those now?

[@user-vo4wc2jz8g]

The auto subtitles open with the words "This stinky little thing..." 😆

[@gregorythomas333]

A little black tape might help keep the light ingress a bit lower.

[@geoffh2760]

Mounting the sensor so that light from the lamp it controls can't reach it and only measures the light falling on it from the sky would greatly help here and prevent feedback.

[@gordonirving24]

ORP12 used to be the go to LDR.

[@TheZombieSaints]

I love you euphemisms Clive. You definitely don't want "nasty tingles"😉

[@seanseoltoir]

Reminds me of what some of the dimmers did when a non-dim-able LED bulb was installed in it... Try it with an incandescent bulb and see what it looks like...

[@wisher21uk]

So simple and no wonder it’s rubbish lol thanks Clive 😊

[@combatclifton]

Wago’s hold soldered wire securely

[@sortofsmarter]

Would love to see how to fix it and or have a latching circuit. Maybe you already did a video about it but with all the 1000's you have I dont remember..lol

[@Mr_Mz518]

I installed the very same bulkhead lamp and had the flcikering light effect with an LED lamp....tis iritating for a while. Definitely designed for incandescent lamps

[@pileofstuff]

I'm surprised that the on resistance of the thyristor doesn't clamp the rectifeid voltage below the zener's ability to keep the gate turned on.

[@KarldorisLambley]

brilliant vid, as always. of late i have have a new found respect for Clive's ability to keep talking, i believe they call it avoiding dead air (interestingly, this must never be done by live TV and radio broadcasters, as if they do the transmitter assumes a fault and switches to a back up, and for a reason i can't recall this is very bad) any-hoo, i tried it. just chatting away merrily as i was taking a thing apart. my lord it is difficult. i am sure i would have to 'cheat' and write an outline and a few ideas. i would also love to see the bench, and the camera, and the things that Clive says "oh no, Ive knocked something over" about. where does his R hand go when he adjusts contrast? i thought at first Clive used a phone on a projection from a shelf, but i think a phone would be too high up to see, yet he adjusts contrast with aplomb, or perhaps the phone is before his face and his hands go round it? no that sounds ludicrous. if there is a vid showing where the magic happen from a different angle i've yet to find it. i have seen vids of Clive doing other stuff in what looks like a nice proportioned room, with egg and dart moulding, in a blue colour, with drawers abaft of him. i have watched hundreds of BC vids, so i am fairly sure there isnt one showing clives bench properly? although, perhaps it is before these drawers, so behind clive in the ludicrous thumb-nail vids? my electronicing is still somewhat of a a curate's egg. but getting better. righto, that's my one over the eight BC rambling for a while. cheer'o.

[@BigClive]

Phone is at a height where I can peek at the screen. Continuous narration came from experience and radio-broadcast principles.

[@ruben_balea]

With that little window flies and spiders would enjoy turning the lights on during the day.

[@mrwoodandmrtin]

Add the indicator light to your tester now. Before the electrocution.

[@curtw8827]

For an additional $1.00 US it will also sense dawn as well.

[@TATICMOOR]

Well, well, well, as usual, you shine as bright as a lightbulb each time to post a video. Good on you, man. I always love to watch your channel in the dark or light, lol. 🪔🕯🔥🔦💡🌙☀️

[@johngalt7382]

Will a minimalist duck sensor detect if the bulb is quacked?

[@fezgary8279]

long time subscriber. Love the videos. Will you look into the ttp223 touch sensors. They have a flicking issue when held on for more than 10 seconds. I dont know if its a power or overheat protection. Anywho. Thank you for the content you provide, very educational, and informative. Love it!

[@uaporin]

those are for filament type bulbs.

[@anthonyjones5711]

Be interesting to see how much pulsed DC that circuit squirts back into the AC supply

[@Steve30x]

I bought a solar street light a few months ago and it seems it has a faulty PIR sensor. It's supposed to remain at 30% brightness until it detects motion. But what it does is keeps going from 100% bright to 30% bright until it runs out of battery. If I knew how to fix it I would attempt to repair it myself.

[@michaelwebber4033]

Most of the ones I work on have light level sensitivity and time delay control. This is beyond simple

[@michael931]

I expected Clive to fix it!

[@toddoroi4947]

I remember when I was a kid I made my own dusk sensors from relays and ldrs and they flickered horribly, the noise was nice though.

[@davidfalconer8913]

Some US street lights used a HUGE CdS unit ( RCA 4403 , nearly 1 inch across , I have one right here ! ) , this passed enough daylight current to energise a 115 Volt relay ... at dusk the relay lost power , contacts switched on , lighting the street lamp ! ... your little unit needs a cheap Schmitt trigger IC ( ? ) ... Ha - Ha ................ DAVE™🛑

[@d.t.4523]

Thank you, now take a coffee break.

[@Boda.Attila]

Is it possible to fix this sensor? Can we incorporate hysteresis using a minimal number of components? This video needs a follow up. 👍

[@DirtyApronBoy]

I'd enjoy a video about the different kinds of diodes and their function

[@tncorgi92]

I haven't had much luck with these sensors, there's a unit on my carport that worked for a few weeks but now stays on all of the time unless the sun is hitting the sensor directly. It's the second one I've replaced. I finally said screw it, the cost of running 2 LED flood lamps is minimal compared to buying new sensors all the time.

[@andymouse]

Not on but not off its in a superposition....cheers.

[@demef758]

Oh, for a second, I thought you were going to review a DUCK sensor.

[@BigClive]

I may change the title. A lot of people seem to think it says duck.

[@MaleAdaptor]

Thanks

[@acmefixer1]

It might help if there was a 10 uF across the zener diode. A 1N4005 in series with the 470k might also help.

[@SirBoden]

All of the yard lights near my fence flicker at dusk. Just enough of their own light bouncing back to turn themselves off. Slightly irritating, not bad enough to warrant a redesign. Suppose a shield around the solar panel would fix the problem.

[@thesteakman8107]

Would it be possible place an inductor inline to smooth out the flickeryness?

[@some-random-guy-l4r]

The real wagos actually hold soldered wire, I tested it

[@medienmond]

Hey Clive, what would be the right way to ptoperly design this type of switch? Can this flicker-generating-illumination-addon-device be improved.in any way, to make it work without issues? ❤

[@BigClive]

The cheap Chinese units use a 555 as a threshold and hysteresis device that can drive a relay directly.

[@HolarMusic]

I recently discovered that there's a fully addressable RGB version of the copper wire fairy lights on Ali and sites like that. The controller and power comes in the form of a USB stick and it has Bluetooth control. Which makes me wonder, how hackable are they? Obviously you could just resolder the string on some other controller, but could you also just reflash the MCU it comes with? Would be an incredibly cheap way of getting any lights you could imagine, like old-school randomly twinkling lights etc.

[@BigClive]

Some use classic 3-wire WS2812B LEDs.

[@Gazr965]

I made a similar thing back when we had filament bulbs, it was based on a TIC 106D SCR, a 100k pot and a resistor(as an end stop), 4 1N4007 diodes and an LDR ( from Tandy) it was pretty crude but worked a treat on a 60 watt bulb, but I doubt it would work as well with the new LED lamps. Ps I read somewhere mains LED lamp bulbs have a limit of on off cycles so could this circuit damage the PSU in the lamp?. Gaz Yorkshire.

[@sergeyneverov]

👍

[@PerspectiveEngineer]

I think you could fix that with the hammer Of knowledge.

[@smthnew861]

I'm disappointed that there were no minimalist ducks :(

[@Nono-hk3is]

Could the total amperage being pulled through the thyristor possibly effect apparent stability of the thyristor?

[@BigClive]

It is intended for low power loads. But electronic loads might cause thyristor latching issues.

[@ralphj4012]

That sound-operated disco lamp isn't fooling anyone (2:46 to 2:54). The Chinese language advert for Chrome at the beginning, sums up everything.

[@smalcolmbrown]

Thanks :)

[@MrRelevance02]

12am watching this

[@Poult100]

I see the thyristor actually shorts the circuitry supply too! That can't be great for stability. I'm surprised it works at all! 🤷🏻‍♂️

[@BigClive]

Once it triggers it latches for that half cycle.

[@Poult100]

I meant to say, the 'stablish' supply doesn't have a reservoir cap!

[@lm7143]

The lights on the m42 m6 toll junction do this must be the same

[@ConstantlyDamaged]

Is the flicker being caused by feedback from the globe? It might be just enough to cause it to flick back and forth over the thyristor's trigger. Seems like a lot of these sorts of issues would be fixed if they could produce an LDR that was only sensitive to UVC.

[@Shakey31]

Hey Big guy. I searched your videos and was hoping to find one on ATX computer power supplies. Any chance you could do one showing how to get different voltages by combining different wires that come out from it? I looked and found some but were in a different language. I'm hoping to get one to charge my camper batteries. 2, 12v deep cycle. Thanks and still love your content!

[@BigClive]

I'd recommend a dedicated charger to extend the life of your batteries.

[@phils4634]

The "Sticky Label Fixture" screams minimalist "engineering". Any chance of a review of these Chinese solar rotating light house devices? they are very good modules for the modelmaker, and run very well on 1.5v. Would it be worth increasing the value of that capacitor? That might reduce the flicker a little?

[@BigClive]

I featured the solar lighthouse mechanism a while ago.

[@deepblueskyshine]

There was a reason to add tin to copper in order to have hard bronze...

[@mrwoodandmrtin]

Could you put a cap across something to stop the flicker? Where would you put it?

[@BigClive]

It's not that easy.

[@mrwoodandmrtin]

@@BigClive An L/C arrangement? There must be a way to slug that twitch.

[@curtishoffmann6956]

No, don't add the power indicator to the death machine! The nasty tingles are why we come here!

[@kentahirono]

what if someone put a 10ish uF cap on parallel to that zener diode?

[@dammonbutler6951]

Is something similar to that (obviously without the LDR) what is inside solid state relays?

[@BigClive]

Yes. Very similar.

[@petersage5157]

I'm curious if there is a simple, minimalist way to add hysteresis to this circuit.

[@BigClive]

Not easy in its current configuration.

[@leongyokeloong5083]

I think using a relay to switch the bulb is better.

[@adamwishneusky]

Could you add anything simple to this to smooth out that threshold area?

[@BigClive]

It would complicate things greatly.

[@rancillinmontgomery2480]

I’ve installed many hundreds of these and if they aren’t aimed away from ambient light sources they will flicker or turn on and off all night long. Sometimes I would paint a piece of sheet metal matte black and place that on the wall and aim the sensor and that or a black plastic tube on it aiming away from light sources and light colored surfaces. Problem solved.

[@reoproedros]

what is the frequency of the dc from the ac conversions through the diodes ? double the grid ?

[@BigClive]

It will still be the same frequency when the rectifier is shunted.