FUN Table-Top Play: Assembling little YARD LIGHTs is Optical Logic ! - Page 1
Forum section: electronics / general

author: RJSV
author_rank: Super Contributor
timestamp: March 20, 2022, 02:20:02 am
content: Hello, again:I've built a 'Totem Pole' of 2 of those ¢99 cent Solar lamps. That helps, because the lower of the two, those being like little 'hockey pucks', sized, the lower one gets held 'OFF', due to sensing light, up top.I even had a problem, at first, when the upper yard light 'puck' stayed on, past 11 pm.So, you have to do some tests, to put the weaker light first, for usable light, from second phase, like 8:30 on to 11:00 pm or later. Just, you won't have ALL your lights going dark at 8:15!For a fun plus; Try stack a few of those little light 'pucks': Idea is to produce, real easy, an EDGE detect, that will outburst a pulse of light, with passing (shadow edge) of your moving hand.Way that works, generally, is first puck1, that lights, and puck2 extinguishes then...Puck3, comes on then, right in fast sequence.You can then imagine...that negative going or 'Low going' edge, of your hand shadow, caused that sequence.But it's neat, to see a bright, quick 'Flash' when hand sweeps by, getting that 'edge detect' response.Other direction hand wave doesn't work...that's part of the edge detect feature seen often.

author: RJSV
author_rank: Super Contributor
timestamp: March 20, 2022, 02:44:19 am
content: And it's not just a little string, of pulsed LEDs, but those are 'invert' or negative inputs, termed much like, in Neurons, the so-called 'Inhibitory' input. In neurons, there are many 'strengths' against a pretty clear 'firing' point (in the living cell).Here, you can, very simply, 'bleed' portions forward, of the light,

author: RJSV
author_rank: Super Contributor
timestamp: March 20, 2022, 04:08:41 am
content: This can opposite, there's the 'Stimulation' inputs, those being to cause outputs.Of course, those Yard Lights act to shut-down, upon too much light, (past that threshold).So, simply, to get a logical invert, just add a 'puck', optical in and optical out.Now, I did notice, when practicing 'Edge Trigger type laall OPTICAL.

author: RJSV
author_rank: Super Contributor
timestamp: March 20, 2022, 04:36:39 pm
content: series of polarityCourse, if you had 10, anclear;the ambient light input will keep each one dark.OK, then if You place them in one after the other order, minimizing gaps, an ALTERNATING on-off-on pattern happens, down the line.For table top trials, it's difficult to hold much more than 4 of the LED 'pucks', but was thinking maybe trying use some 'card' sized square base scotch-taped toYou could imagine; two pucks each points to a third, and with some differences in spacing, they don't mix 50/50. Like, suppose the two 'inputs' are porportioned as:First puck#1: 20 % of thresholdSecond puck#2: 30 % of threshold.Notice, You stillAny Ambient light is often considered 'static'

author: RJSV
author_rank: Super Contributor
timestamp: March 21, 2022, 07:19:52 pm
content: Having a good OPTICAL Signal table, there, placing LED totally up against the solar cell, of the 'first' of 3 yard lights (hockey puck shaped).That, first LED light will convert to white light, (from the starter blue led), and actually inverts, so goes dark in little pulses. Then, and this is the interesting part, for best results; The yard light #2 must be several inches extended over, (away), that way those little 'dark' stabs from light#1 have a chance...Hard to comprehend / explain that mechanism, but with the (longer) spacing you get a more obvious pulsing.Then, a third yard light converts, yet again inverting, that nice, definitive 'low going' light pulse, into a bright and quick 'Flash', as most folks associate as being a 'good impulse' indicator.I don't know, what 'u

author: RJSV
author_rank: Super Contributor
timestamp: March 24, 2022, 07:26:14 am
content: situation, very close to conventional flip-flop really.With each (on table top), put at 90 ° degree points, incredibly, there is a (delicate) positioning that gets each able to illuminate the next, and with enough light to trigger that 'inhibit' response, of suppressing LED output.Kind of like, 2 'dragons, each consuming the other's tail...', only this is '4' dragons...all around the circle.I believe that the 4 pin device, is a simple processor, maybe cost less than ¢ 1 cent, (1884 prices).But that simple, 4 pin, looks like a regular small black plastic transistor.The little square Solar Cell, on middle of each 'puck', gives off over 1.4 Vdc when in bright light. That is, just the cell, as component, not in circuit.Guess is, there is the processor to do the LED switch off when daylight, but perhaps some other delay, like 50 mSec from a capacitor, or 'soft' turn on actions, would cause each individual puck, to have a 'palpatle' delay, especially with several or more (in serial order).At any rate, a simple interruption, of that 'QuadraGate' will 'flip' the total state, but it's really just like having a standard, 2 LED flip-flop, there is just 'another' pair, in lockstep. And, of course, to change that operation back you just 'interrupt' the optical path, with couple fingersLike I said, it's fun, exploration into switching, while keeping things light; No Wires or pwr supply's, except inside the little pucks.

author: RJSV
author_rank: Super Contributor
timestamp: March 24, 2022, 07:35:42 am
content: Another possible configuration adds since phases get reversed passing thru each Solar Lawn device.Three, around circle, looks cute, but don't work, the light has to 'bend' around too much, although some reflecting white paper surround helps that.Avoiding that by going to, phase-unstable 3 units around, the circle.Going to the ¢99 cent store tomorrow, maybe buy a few additional LED yard lights!

author: RJSV
author_rank: Super Contributor
timestamp: March 26, 2022, 02:48:28 am
content: You can see that, going around the circle.SURPRISED, the thing even works, with 'minor' adjusting each piece, there, in table.

author: RJSV
author_rank: Super Contributor
timestamp: March 26, 2022, 02:51:43 am
content: You can see, partially, in photo the one LED yard light is brightly glowing, but in action, the situation alternates ; ON -OFF -ON -OFF around, each at 90 degrees around.Fun to play with, as a bit finicky.

author: RJSV
author_rank: Super Contributor
timestamp: April 08, 2022, 02:39:14 am
content: Good news, replaced old camera...(still a little glare-scatter but should be tolerable.)The first photo, gives a bird's eye view, before adjusting, but can (clearly) see those 4 solar yard lights are arranged as a FLIP-FLOP, or more accurately, as a'FLIP-FLOP-FLIP-FLOP' but with Bi-Stable action.It's, literally, an optically interfaced single bit memory!Second picture, needed overhead light (simple kitchen lamp), plus a small light reducing block, on the bright window side. That 'steady' ambient light adjusting is forming a measured , careful bias, say,40 % of trigger requirements.Note that this post is a bit duplicative of early posts on this topic. However, Photo Clarity was sub-par.That's because, those AMBIENT light sources can manipulate the triggers, in the contained little yard light circuit 4 Pin IC.Pulses can be manipulated, usually making final unit pulse very much shortened. I can, already make up some other functions, including OSCILLATION, the holy grail, of electronics signalling.Four bucks, or a little more, gets you set, go local hardware store, or, often, drug stores (more available in holiday season.)Rick B.

author: RJSV
author_rank: Super Contributor
timestamp: April 08, 2022, 02:40:30 am
content: Flip flop 'SET' view.

author: RJSV
author_rank: Super Contributor
timestamp: April 08, 2022, 02:41:43 am
content: ...call this one, 'RESET', state.

author: RJSV
author_rank: Super Contributor
timestamp: April 08, 2022, 07:13:17 am
content: Right now, I have 3 (slightly) different varieties, of those ¢99 cent light 'pucks'. I'm expecting, soon, to get some 'characterizing' data; simple measurements using 'distance', and ambient light present. Using a 'Zoom' call setup, up above table-top, to create an informal metric, of ambient light.For some major mods, you've got to bring out, a couple wires and connect (more) obvious electronics,but be wary, there are numerous, and lethal hazards, taken into younger students...Such as swallowing hazards, so...be aware, there.Of course, somebody could, in matter of a couple minutes, 'point' SIX of those LED lights, around circle, creating a SIX way flip flop, but having only 2 states, holding a single bit. (They need to be charged, elsewhere, outside in SUN.)Another aspect, of an optical test bed, is various configured curvy housings, white or silver reflecting, perhaps to make a 'two' element flip-flop.OR, someone could try, invent a 'Voting' flip flop, having 3 inputs, voting in an analog equivalent, using separation distance.

author: RJSV
author_rank: Super Contributor
timestamp: April 08, 2022, 07:30:45 am
content: For (slightly) more distant optical reach, industry has used optical 'Choppers', often a motorized baffle, interrupting beam, at 80 hz. Course, that's old school (1975), but you've got advantage, using AC amplifier at receiver end, for increased sensitivity to the light beam.(Optical fire detection used signal chopping, instead of DC or static light levels, to convey over distance.

author: RJSV
author_rank: Super Contributor
timestamp: April 09, 2022, 03:53:07 am
content: Oscillation DOES occur, but fleeting, so far, looking like somewhere between 10 Hz and, (?), perhaps 45 Hz,nevertheless, the contraption goes unstable, dimming into 'buzz', for further 'O Scope checkout.(Tektronix 465).Just a matter of minor tweaks, and placement, of a control-able LED 'Zoom ring', rigging up tripod, etc.With warfare outrages I feel compelled to say, at least, I do not like tragic events, (lost for proper words, really).I'm moving things along, as some people are as well.Helpless, to a degree, really.==================================

author: RJSV
author_rank: Super Contributor
timestamp: April 09, 2022, 03:54:06 am
content: 5-WAY LED LIGHT RING

author: RJSV
author_rank: Super Contributor
timestamp: April 09, 2022, 04:11:28 am
content: .

author: RJSV
author_rank: Super Contributor
timestamp: April 09, 2022, 04:38:06 am
content: At a certain height, that set-up will generate a 'sharpened' light pulse, over at the ultimate last LED light, (not in ring config, this time). That means, first couple of light 'pucks' do pulse, but for 1/3 second, or so...meanwhile, at end of line-up, that light flashes fully bright an quite fast (80 mSec ?).However, and this is interesting challenge, to explain:Holding that pen, as a narrow light block, at just the right height, (within +/- 1 mm), will allow that 'Optical Logic' to generate a 'Pulse', but only when pen is moved towards (observer), and so has directional sensitivity...I believe, that will turn out to have different exact response, as light path is, to say the least, different, as that little pen is swept past the first and second LED puck (looks like a little sports 'puck',

author: RJSV
author_rank: Super Contributor
timestamp: April 10, 2022, 05:39:32 am
content: for a time per

author: RJSV
author_rank: Super Contributor
timestamp: April 10, 2022, 05:52:19 am
content: for making up the difference, so the thing functions as a level triggered comparator, digital output.