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Learning basic electronics by building fireflies

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Re: Learning basic electronics by building fireflies

#61

Post by bombela »

Liftyee wrote: post #30
bombela wrote: post #21

Earlier quoted context omitted.

I have a bag of attiny13a that cost me $0.20 per chip. It is fully self contained. Just add a very small capacitor, give it from 2.8V to 5V. And then you program it the way you want. You can even program and debug it via a single pin if you wish. At this cost for a hobbyist it's just hard to beat. It can be anything you want it to be in a few lines of code. I personally write Rust for it, not Arduino C++, but it woul…

What toolchain do you use to compile Rust for it? I have about had enough of undebuggable random Arduino segfaults.

The main Rust compiler. https://doc.rust-lang.org/nightly/rustc/platform-support/avr...

Re: Learning basic electronics by building fireflies

#62

Post by Auracle »

somerandomdude2 wrote: post #33
octaane wrote: post #31

As an aside, the disappearance of insects is noticeable elsewhere. I'm a big fishing guy, have been my whole life. Many old-timers I know have commented on the lack of insects. We've all noticed that certain flies and lures have stopped working, or at least, have significantly reduced efficacy. We think it's because for at least several generations (fish have short lifespans), they haven't been exposed to those insec…

I've heard that too. But, from my experience, it's mostly insecticides: people want mosquito-free and flea-free (and ants, roaches etc) yards, and spray/spread poison that kills them. Unfortunately, it kills everything. I cancelled my yard service and noticed that birds started coming back, chasing the food supply. Butterflies cover my lantana, and I see fireflies at night.

I live in Minnesota and the struggle is tough. Either my yard is completely unenjoyable for the family due to mosquitoes and deer flies some years or I kill 50 insects that I don’t want for every one that I do.

I put up deer fly traps every year and that helps, but this year in particular has been awful for both them and mosquitoes. Luckily for the bugs my sprayer is broken and I haven’t had time to fix it.

I deliberately avoid the place on our property where fireflies are, on the years that I do spray. We really need a better solution.

Just to be clear, if we go outside right now we instantly have multiple deer flies trying to land on us and bite, which is only a distraction for the mosquitoes. Without swatting I’d probably get a mosquito bite a minute midday or maybe 5-10 a minute at 7pm.

Re: Learning basic electronics by building fireflies

#65

Post by johnisgood »

yapyap wrote: post #23
yojo wrote: post #17

Only tangentially related to the enthusiastic circuit hacking: the reason the author stopped seeing living fireflies may be the drastic, worldwide decline in insect populations, with biomass declining in the range of 2-10%/year[0]. https://en.m.wikipedia.org/wiki/Decline_in_insect_population...

jesus christ

Funnily enough, I moved to another apartment which is right by the main road (the sound pollution is driving me crazy, not recommended), and now I have an insect problem. Every night I am fighting moths and dragonflies. Never had an issue in my previous apartment. Both are deep in the city, although the current one has more greenery nearby.

Re: Learning basic electronics by building fireflies

#66

Post by Nitor »

btbuildem wrote: post #42

> so I searched the web and found tinkercad.com has a circuit simulator where you can drag and drop all the components and see if and how it works. It worked for simple circuits, but for mine, the astable multivibrator, it didn’t for some reason. I tried falstad.com/circuit; the same thing happened. It also didn’t work. I searched the web for the reason, and I’ve noticed that sometimes these simulators don’t work wel…

For hobby use I have found it best to do circuit design and simulation in different pieces of software. LTspice for simulation and KiCad or EasyEDA for PCB design.

Fully agree that your mind has to be a particular type of broken to click with all of these. I love LTspice for its simulation tools, for example the ability to vary a component value over time in a transient simulation, but it is a software that fights you at every turn when you try to learn it.

Re: Learning basic electronics by building fireflies

#67

Post by zavec »

JKCalhoun wrote: post #51
Workaccount2 wrote: post #2

The juxtaposition between the cleanliness of the software and the absolute travesty of a schematic is jarring. But it still works! I applaud the author for wading into analog electronics. Pretty much everyone nowadays would just put a timer on a micro and be done in 2 minutes. No fun in that. There is something to be said about the minimal elegance of purely analog designs, and a special rewarding feeling for wrangli…

Yeah, for me, analog is the exciting domain — my undiscovered country. I have played with vacuum tubes as well and thoroughly enjoyed it. Transistors were, for some reason, seemingly unknowable to me. But I made a kind of "transistor playground" [1] based around Forrest Mims III book [2] and then enjoyed playing with them. [1] https://imgur.com/a/dChq4AZ [2] https://archive.org/details/forrest-mims-basic-semiconducto…

That looks awesome, nice work! Very clean.

Re: Learning basic electronics by building fireflies

#68

Post by fc417fc802 »

iaaan wrote: post #49
btbuildem wrote: post #42

> so I searched the web and found tinkercad.com has a circuit simulator where you can drag and drop all the components and see if and how it works. It worked for simple circuits, but for mine, the astable multivibrator, it didn’t for some reason. I tried falstad.com/circuit; the same thing happened. It also didn’t work. I searched the web for the reason, and I’ve noticed that sometimes these simulators don’t work wel…

The naive programmer in me wants to assume, "It can't possibly be that hard to simulate a circuit," and get to work on prototyping my own simulation engine but the fact that this apparently has not ben adequately solved yet gives me pause.

It depends on what level of detail you want the simulation to have. Boolean logic is easy. Analog circuits operating in certain (very limited) domains are straightforward. But - noting that what follows is well out of the realm of my experience - in other domains you have to account for things like RF characteristics and quantum effects in the semiconductors.

Imagine trying to simulate something that used water in tubes to implement logic, except it's analog logic and there's resonance and some of the joints start leaking when they exceed a certain pressure and etc.

Re: Learning basic electronics by building fireflies

#69

Post by ethan_smith »

bee_rider wrote: post #16

Fireflies flash in response to lights. I wonder if a photoresistor sensitive enough to respond to his “firefly” can be found. Then he could rig it up so his fireflies communicate with each other. And maybe real fireflies as well. It would have to be pretty danged sensitive I guess. Extra points if the circuit can be rigged up to respond to changes in brightness, so that it doesn’t constantly trigger in daylight….

This is achievable with a simple photoresistor and transistor arrangement - real fireflies actually synchronize this way. Adding a CdS photocell in series with a resistor to the base of your existing trigger transistor would make the circuit flash in response to external light pulses while maintaining its autonomous oscillation.

Re: Learning basic electronics by building fireflies

#70

Post by x______________ »

bee_rider wrote: post #16

Fireflies flash in response to lights. I wonder if a photoresistor sensitive enough to respond to his “firefly” can be found. Then he could rig it up so his fireflies communicate with each other. And maybe real fireflies as well. It would have to be pretty danged sensitive I guess. Extra points if the circuit can be rigged up to respond to changes in brightness, so that it doesn’t constantly trigger in daylight….

I was thinking along the same lines, create artificial fireflies to attempt and lure others back into the neighborhood..

But then again, fireflies use their lights to attract mates, and I'm thinking now that their phosphorus-based communication might be more complex than just a randomly emitting diode.

I can picture it now... "You're into WHAT?!? Nope, I'm out of here!"

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