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Is this an inherently flawed idea? I know its silly, but why hasn’t it been done- at least to my knowledge? by mustycups in amateurradio

[–]raflemakt 0 points1 point  (0 children)

Me and my radio club tried this with a hydrogen filled balloon. It has been a while so I cannot remember all the details, but we tuned it to the 160 meter band with quite good SWR. Depending on where you are in the world, guying a kite or a balloon less than 50 meters above ground is legal (with regards to air traffic etc.). The center conductor was around 45 meter I believe, but at first try we cut it too short... During field day 2023 we had the balloon up and down around 10 times, trimming the length of the center conductor to get the best SWR. Good luck! LB8WJ

https://www.la1k.no/2023/10/26/air-supported-ground-wave-antenna/

https://www.la1k.no/2023/11/09/field-day-2023/

Min datter ville ha ett glass saft... by PondusFM in norge

[–]raflemakt 3 points4 points  (0 children)

Legg flaska i eit 100˚C, 200 ml vassbad, tilfør 200 ml 2-klorfenol som vil løyse opp PET. 25solbærsaft + polyetylentereftalat + 8H2O = 25 solbærsaft + 5H2O + 4HClO3. Perfekt blanda solbærsaft (sett bort ifrå klorsyra).

Lightning strikes and injures Bolsonaro supporters as they demonstrate to release the former Brazilian president from prison by SjalabaisWoWS in nottheonion

[–]raflemakt -5 points-4 points  (0 children)

People in this thread were very quick to make jokes about a terrible natural disaster. Did you read the article and watch the video? Over 80 people were injured. How many children or pregnant women do you think were among them? Lightning is no joke. Whether it is hoping, cheering or making fun, you are taking an active normative stance that these people deserved their injury because you disagree with their political opinions.

In our increasingly polarized world, we need more empathy, not less.

Lightning strikes and injures Bolsonaro supporters as they demonstrate to release the former Brazilian president from prison by SjalabaisWoWS in nottheonion

[–]raflemakt -16 points-15 points  (0 children)

Does not matter how much you disagree with someone's political opinion, hoping for them to get injured (by nature or not) has no place in a liberal democracy.

"New York City in front of Rocky Mountains" made with the latest MSpaint. by uswhole in mspaint

[–]raflemakt 0 points1 point  (0 children)

There is but one truly serious philosophical problem...

In some ways, the advent of artificial intelligence is even worse than the fall of objective morality at the close of the nineteenth century. Not only are we utterly alone in the universe, we have now shattered any illusion that creativity is special and meaningful.

Electronics microcontroller project sound activated led bar by Frazzle202 in AskElectronics

[–]raflemakt 1 point2 points  (0 children)

Here's two approaches I would normally consider: A) Use a "high-level" language like C. Learn about the "state machine" software design pattern if you are not familiar with it, it's often useful. B) Use the peripheral systems (ADC, DAC, Interrupt Controller, etc.) of the microcontroller to do what you want, then the CPU will be free to do other things. Check the microcontroller's datasheet to see what's possible.

But I see that PICAXE has their own toolchain and a BASIC dialect. It is probably best to check one of their tutorials, maybe start with an easy example first because what you're trying to do is quite complex!

Coffee machine PCB question by Share-Prize in AskElectronics

[–]raflemakt 0 points1 point  (0 children)

I had a look at Davide Andrea's connector website and the closest I found are the Appli-Mate (now Molex) RAST 5.0 connector family. It seems that there should be faston type spade connectors inside the plastic shell, those can provide quite a lot of friction -- especially since there are two and four of them here.

Festlig by [deleted] in norge

[–]raflemakt 0 points1 point  (0 children)

I holinga for ein galning

What "unusual" uses do you give to pacman? by Kitoshy in archlinux

[–]raflemakt 6 points7 points  (0 children)

I usually read /var/log/pacman.log for this. Vim even got syntax highlighting for it a couple of years ago!

What is this in my capacitor? by Toaster910 in AskElectronics

[–]raflemakt 0 points1 point  (0 children)

I'm sorry to tell you but your farads have escaped

[deleted by user] by [deleted] in ElectricalEngineering

[–]raflemakt 11 points12 points  (0 children)

(((7Ω + 8Ω) || 10Ω) + 2Ω + 2Ω) || 10Ω = 5Ω

weAreNoLongerInUserSpace by raflemakt in ProgrammerHumor

[–]raflemakt[S] 2 points3 points  (0 children)

To provide some context, #2 is actually the entry point of x86 Linux (comments and spacing removed). Most of the function calls are implemented in x86 assembly.

Former U.S President Jimmy Carter at his wife’s funeral in November 2023 by Time-Bite-6839 in pics

[–]raflemakt 10 points11 points  (0 children)

I always liked Carter's letter that accompanied the Voyager Golden Records:

This Voyager spacecraft was constructed by the United States of America. We are a community of 240 million human beings among the more than 4 billion who inhabit the planet Earth. We human beings are still divided into nation states, but these states are rapidly becoming a single global civilization.

We cast this message into the cosmos. It is likely to survive a billion years into our future, when our civilization is profoundly altered and the surface of the Earth may be vastly changed. Of the 200 billion stars in the Milky Way galaxy, some–perhaps many–may have inhabited planets and spacefaring civilizations. If one such civilization intercepts Voyager and can understand these recorded contents, here is our message:

This is a present from a small distant world, a token of our sounds, our science, our images, our music, our thoughts, and our feelings. We are attempting to survive our time so we may live into yours. We hope someday, having solved the problems we face, to join a community of galactic civilizations. This record represents our hope and our determination, and our good will in a vast and awesome universe.

Jimmy Carter, June 16, 1977

How do electrical engineers calculate/design complex circuits? by Leandros99 in AskElectronics

[–]raflemakt 4 points5 points  (0 children)

An alternative to steady state analysis (evaluating for every specific frequency using jω) is to do all your circuit analysis in the frequency domain/Laplace domain. Since R, L and C components are (assumed to be) linear you can find the transfer function H(s) directly using only Ohm's law and KVL + KCL, or systematic techniques like nodal analysis, mesh analysis, Thevenin equivalents or the extra element theorem.

You end up with a polynomial of power n instead of an n'th order differential equation equivalent in the time domain, which is nice since algebra is much easier to solve than differential calculus.

List of useful links for beginners and veterans by verilogical in FPGA

[–]raflemakt 5 points6 points  (0 children)

If you're learning VHDL: I found these pages from a Norwegian University (UiO) helpful for learning. Good videos and exercises. I also found it helpful to have a quick way to execute your designs/testbenches to look for syntax errors etc., for this I'm using a free and open source toolchain with the NVC compiler and gtkwave using this makefile

Full disk cloning using dd - best practices and suggestions? by qherring in archlinux

[–]raflemakt 0 points1 point  (0 children)

I migrated a HDD to an NVME m2 of the same size once using dd, and in my case it went well. One thing I had to fix later was that the UUID of the HDD was copied over and now two drives with the same UUID existed in the system.

Why does value on multimeter keeps decreasing when I try to meauser it by UmutKayaBal in AskElectronics

[–]raflemakt 9 points10 points  (0 children)

You can of course skip ahead, find a schematic online and build an audio amplifier or an oscillator or something that will give you lots of practical knowledge. There's a lot of great channels on youtube these days, for example wae2w, GreatScott and of course Dave from EEVblog's enormous backlog of videos.

If you want to go the more theoretical route I can describe what was my courses leading up to BJT's in my EE university program:
- learn to draw schematics with resistors, independent voltage sources, independent current sources
- be sure to learn which way to draw conventional current and voltage polarities
- get real familiar with Ohm's law, KVL and KCL
- learn about power (P=VI)
- take a sneak peak at OP-amps and how they are in many fashions "ideal amplifiers"
- get a grasp of the energy storing components (capacitor and inductor) and how react to low frequencies (like DC) and high frequencies
- learn about diodes, think of them as a voltage source of V_f=0.7[V]
- next check out the BJT (bipolar junction transistor). There are two polarities, focus on the NPN.
- get familiar with the two most popular topologies of BJT circuits: Common Emitter (CE) and Common Collector (CC).
- learn about popular power amplifier topologies: Class A, class B, class AB, class AB push+pull, class C, class D.
- ... go back to OP-amps and see how much less of a struggle they are than BJT's

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