🎓 Doc Freemo 🇳🇱 @freemo@qoto.org

@Electronics

I wanted to share a write up I did not to long ago explaining **circuit duals** with a specific focus on **magnetic circuits**. They behave the same as an electric circuit in the sense that anything you can do with an electric circuit there is an equivalent way to do it with a magnetic circuit. A magnetic circuit is a circuit that uses the magnetic fields propagating through "wires" rather than electric fields. It's a very cool idea and worth a read, though all the usual electric concepts are flipped, for example instead of talking about electromotive force (EMF/voltage) you would use magnetomotive force instead (MMF) as filling the same function as voltage in an electric circuit.

Let me know what you think, this tutorial was a week long effort to write.

https://jeffreyfreeman.me/an-indepth-look-at-duals-and-their-circuits/

#Electronics #RF #HamRadio #amateurradio #EE #Radio @General

@Electronics

Finished most of the #ROES prototype board. Never have I been so excited to solder something, specifically the shield. After several years of hard work putting that shield on was a trophy! Its something that has collected dust for periods too and this is the second version I went full cycle on.

For those wondering this is the RF analogy board for an advanced highly percise SWR meter with Network-analyzer like capabilities built into an #Arduino shield. It measures a radio signals forward and reverse properties and compares them including complex impedance, complex reflection coefficient, SWR and much more. with two of them and a zigbee you can even operate one at your transmitter and the other at the antenna end and get both readouts in the shack. Cool stuff!

The yellow shielded wire wasnt working so I added a very tiny red wire instead. The final product wont need this and it may introduce some issues with the prototyping, lets hope not.

If you want to see more pictures of the project, including the GUI demo running or the earlier v1 version just check out the #ROES hashtag.

#electronics #EE #RF #Radio #HamRadio #amateurradio #Science #ElectricalEngineering #Arduino

Man ive been at this over 2 hours now and havent even covered a square inch yet. It messes with your head how damn small these 0402 components are.

@Electronics #Electronics #EE #HamRadio #amateurradio #arduino

@Electronics

Man soldering 0402 components is brutal. I wouldnt wish this on my worst enemy... but progress is being made!

#Electronics #RF #HamRadio #AmaetureRadio #EE #Arduino

@Electronics
About to start soldering up my #ROES prototype. This will be fun.

#Electronics #RF #EE #HamRadio #AmaetureRadio

@Electronics

Every damn time...

#Meme #Funny #Electronics #EE

@Electronics
This is either a 250kW Automatic Tuner, or they take their Irish Whiskey production very seriously.

#HamRadio #RF #Radio #Electronics #EE @General

@Electronics

I feel like this is how the Raspberry Pi should have been packaged from day one, just built directly into a keyboard.

#Electronics #RaspberryPi #Computing #Technology

@math

The ladies version of the classic ohms law cartoon.

#electronics #cartoon #drawing #EE

@Electronics

Wanted to share my prototype design for the #ROES meter with the Electronics Group.

About a month ago I sent the boards off to be printed for a prototype run and recently got them in. So V2.0 is soon to be officially released (though I may do a minor revision before printing up a large number of boards).

Attached are some screenshots of the final schematic and some renderings of what the boards will look like when its done. Its a 4 layer board though so many of the traces are internal.

You can find the files for this, which will be released as open-source, here:

https://git.qoto.org/roes/roes-hardware/

#Ham #HamRadio #Radio #RF #EE #Electronics #ElectricalEngineering #Science

@Electronics

I wanted to share my favorite circuit simulator to the electronics group. It isnt the most advanced and it wont replace professional tools. But its great at modeling semi-ideal components with an epic way of visualizing current and voltage that just makes it an amazing tool at getting a feeling for how circuits actually work.

Everyone should check it out and play with it, you wont regret it.

https://www.falstad.com/circuit/

#Electronics #electricalEngineering #RF #HamRadio

@Electronics

**Hello everyone welcome to the group**. I'll kick it off with some pictures of a style of protoboard I absolutely love. Its great for RF stuff and even if it isnt rf, lets face it, SMD is better!

#Electronics #RF

Anyone out there who is entry-level in electronics or even just a hobbyist with no expiernce want a job? Its a sales job though, which is why you dont need really good electronics expiernce, but there is room to do actual EE too if that's your end goal.

Send a DM if interested.

#electronics #job #jobs

I cant help but feel it would cost almost as much to build this fake as it would to just build the capacitor the correct way....

#Electronics #EE #ElectricalEngineering

A picture of a Radio Shack circa 1950. Its a shame self-repair is virtually non existent and shops like this and radio shack themselves, are quickly disappearing. I remember when I was younger you could go there and any electronics part you could imagine. Now they cant even give away what little inventory they have.

#electronics #EE #ElectricalEngineering #Radio #HamRadio

FYI to all my Electronics people out there.

Did you know you can represent capacitance and inductance with a complex number and by doing so you would incorporate ESR (equivalent series resistance) into your equations. Essentially you dont have to model with idealized components and add in the parasitics manually, you can add the parasitics directly into the capacitance or inductance of your components!

See the following equation in my blog and the subsequent explanation if you want some further details and examples: http://jeffreyfreeman.me/an-indepth-look-at-duals-and-their-circuits/#mjx-eqn-realcap

#electronics #electricalengineering #EE #HamRadio #AmaetureRadio #Physics #Science #QotoJournal

My article is finally up on reddit (had trouble getting the moderators to approve it for some reason). As a result it hidden for over a day. Any of you who are redditors check it out over there and if you like it give it some love.

https://www.reddit.com/r/electronics/comments/j1qku4/an_indepth_tutorial_about_modeling_circuit_duals/

#Electronics #EE ##RF #HamRadio #AmateurRadio #Science #Physics #Math #Maths #mathematics

For those of you who enjoyed my recent blog post on Circuit Duals and Magnetic Circuits I have now compiled a version of it in PDF if you want to keep a local copy or have it for reading on on an e-reader. Feel free to distribute the link.

https://drive.google.com/file/d/1fECh_IeFYBHoFuaw08zO2dkluZPunkP7/view?usp=sharing

For those of you who are just now hearing about it the article describes the idea of Duality in math, how it applies to circuits, how to calculate duals for systems of equations, and a few examples of circuit duals. It also goes indepth on magnetic circuits as a dual of electric circuits. There is an interesting blurb at the end about how to extract energy from permanent magnets as well.

If you prefer the more colorful blog link instead, which will also be the only place I make corrections or update it most likely, the link for that is as follows:

http://jeffreyfreeman.me/an-indepth-look-at-duals-and-their-circuits/

#Electronics #EE ##RF #HamRadio #AmateurRadio #Science #Physics #Math #Maths #mathematics #qotojournal

So two weeks working on this article about Circuit Duals and Magnetic Circuits and it is finally finished and published! Check it out!

Its about mathematical duals and how they relate to electric circuits. I cover several common circuits as duals and how to calculate duals. Bu I also describe a rarely known type of circuit dual called a magnetic circuit that uses the magnetic field instead of an electric field to do all the things an electric circuit can do and explain magnetic inductors and capacitors. It's pretty cool stuff, I even touch on how you can extract energy from the magnetic field of a permanent magnet to power a magnetic circuit (or an electric circuit for that matter.

http://jeffreyfreeman.me/an-indepth-look-at-duals-and-their-circuits/

#Electronics #EE ##RF #HamRadio #AmateurRadio #Science #Physics #Math #Maths #mathematics #QOTOJournal

Ok I think my article will be ready to be published tomorrow after I do one more re-read in the morning.

In the meantime I'd really appreciate anyone giving it a read and seeing if they find any errors please. I really could use some final eyes on this before I publish it live!

http://beta.jeffreyfreeman.me/an-indepth-look-at-duals-and-their-circuits/#the-voltage-current-dual-under-parallel-series-transformation

You can suggest edits direct on my repo or here, I will be happy to give a thank you link at the bottom to anyone who helps.

n the source for my blog:

https://git.qoto.org/freemo/freemo-site-beta/-/blob/master/source/articles/2020-09-22-an-indepth-look-at-duals-and-their-circuits.html.md

Its about mathematical duals and how they relate to electric circuits. I describe a rarely known type of circuit dual called a magnetic circuit that uses a magnetic field instead of an electric field to do all the things an electric circuit can do and explain magnetic inductors and capacitors. Its pretty cool stuff, I even touch on how you can extract energy from the magnetic field of a permanent magnet to power a magnetic circuit (or an electric circuit for that matter.

#Electronics #EE ##RF #HamRadio #AmateurRadio #Science #Physics #Math #Maths #mathematics