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Learning basic electronics by building fireflies

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Re: Learning basic electronics by building fireflies

#51

Post by JKCalhoun »

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-semiconductor...

Edit: actually, I had forgotten it was a transistor logic playground for I made for creating logic gates with transistors. Based on another Forrest Mims book: https://archive.org/details/engineersmininot00mims

Re: Learning basic electronics by building fireflies

#52

Post by dgacmu »

cluckindan wrote: post #28
jabedude wrote: post #11

Earlier quoted context omitted.

I haven't touch anything like this in a good while, how cheap could I get a simple Arduino style chip with a few gpio to drive a yellow LED in 2025?

If you just need it to blink at some interval, get a NE555 for a dime. Granted, you can almost get a microcontroller for that price…

You actually can: The Puya PY32 ranges from about $0.08 on up (well, $0.15 if you only want to buy 5, but the cheapest one is $0.0959 in qty 200 and $0.0676 in qty 5000+). ARM Cortex m0 in a 10-pin ESSOP-10 surface mount package: https://lcsc.com/product-detail/Microcontrollers-MCU-MPU-SOC...

Kind of mind-blowing. 24mhz 32-bit computer for under a dime.

But you'll learn more about the analog-ish world and not need to deal with SMD if you go the 555 route. And it'll save you power vs the astable monovibrator with NPN transistors.

Re: Learning basic electronics by building fireflies

#53

Post by JKCalhoun »

diggan wrote: post #13
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…

> Pretty much everyone nowadays I think it depends on the ecosystem. It's true much of the "maker" community tends to embrace whatever solution is the cheapest, fastest and easiest to get something working out the door, but on the other hand, the DIY synth community tends to be the opposite (in my experience at least), favoring simple schematics and "back to basics" building, even sometimes going as far as trying to…

This would include people building guitar pedals.

Re: Learning basic electronics by building fireflies

#54

Post by JKCalhoun »

dqh wrote: post #39
blackguardx wrote: post #36

Earlier quoted context omitted.

I have a B.S. and M.S in EE. In undergrad, I took a class where we had to solve a different problem using a new analog circuit each week. At first, we could only use BJTs, resistors, and capacitors. Eventually, we made 555 timers from discrete transistors and "unlocked" that IC for future use. At some point we were allowed to use opamps and other ICs as well. This class was the hardest class I have ever taken in my l…

This sounds incredible and makes me want to go through a similar learning process. I don’t suppose anyone could recommend a book or course along these lines?

A lot of us started out putting together some of the circuits in Forrest Mims Radio Shack books [1]. He does a good job of explaining how they work as well.

And then there is an amazing site with (thousands of ?) electronics hobbyist magazines archived [2]. If you want to start browsing, they often ran series in their issues along the lines of "getting started in electronics". Regardless, some awesome projects in there.

But if you want to go back pre-transistor (ha ha) the U.S. Navy had a great series on learning electronics [3]. Def. analog.

[1] https://archive.org/search?query=Forrest+Mims

[2] https://www.worldradiohistory.com/Popular-Electronics-Guide....

[3] https://archive.org/details/basic-electronics-volumes-1-5-by...

Re: Learning basic electronics by building fireflies

#55

Post by jacksavage »

dqh wrote: post #39
blackguardx wrote: post #36

Earlier quoted context omitted.

I have a B.S. and M.S in EE. In undergrad, I took a class where we had to solve a different problem using a new analog circuit each week. At first, we could only use BJTs, resistors, and capacitors. Eventually, we made 555 timers from discrete transistors and "unlocked" that IC for future use. At some point we were allowed to use opamps and other ICs as well. This class was the hardest class I have ever taken in my l…

This sounds incredible and makes me want to go through a similar learning process. I don’t suppose anyone could recommend a book or course along these lines?

The Art of Electronics is an incredible resource. They have a companion book which guides you through hands-on labs. I have not read it, but I trust that it would be worthwhile.

https://learningtheartofelectronics.com/

Re: Learning basic electronics by building fireflies

#56

Post by andreareina »

I wonder how much of the simulators not working is due to these circuits taking advantage of parasitics. IIRC the original joule thief circuit doesn't have a capacitor despite one being required for boost circuits; physical components have stray resistance/inductance/capacitance that have real effects on the circuit.

Re: Learning basic electronics by building fireflies

#57

Post by andoando »

jabedude wrote: post #11
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…

I haven't touch anything like this in a good while, how cheap could I get a simple Arduino style chip with a few gpio to drive a yellow LED in 2025?

You can get a bluetooth/wifi enabled microcontroller like a Pi Pico 2 for $5 or a full on computer running linux for $15 (Pi zero 2)

Re: Learning basic electronics by building fireflies

#58

Post by relwin »

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….

Le Dominoux do something similar, triggered off each other, and uses a 555: https://youtu.be/PQOjkuJtBfM?si=8J2taYoicQEtJJJB

Re: Learning basic electronics by building fireflies

#59

Post by justaj »

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…

I still can't get over the fact that all electronics schematics is actually in reverse and everyone is still fine with that.

Re: Learning basic electronics by building fireflies

#60

Post by rickydroll »

stared wrote: post #29

> I love fireflies. But in recent years, they stopped coming for reasons I don’t know. No tiny, glowing dots in the dark like they used to. I miss them more than I expected. Light pollution, and even more: pesticides. Population of all insects fall dramatically. "Three-quarters of flying insects in nature reserves across Germany have vanished in 25 years" - https://www.theguardian.com/environment/2017/oct/18/warning-…

As I understand it, fireflies are vulnerable to lawn chemicals and light pollution. They spend something like 2 years as grubs and then a few weeks as adults above ground. Lawn/in-ground pesticides kill the grubs, and light pollution interferes with finding a mate.
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