Lmst

When Electricity Doesn’t Take the Shortest Path https://hackaday.com/2026/01/13/when-electricity-doesnt-take-the-shortest-path/
#Science #Impedance #Reactance

When Electricity Doesn’t Take the Shortest Path

https://web.brid.gy/r/https://hackaday.com/2026/01/13/when-electricity-doesnt-take-the-shortest-path/

<div><img alt="" class="attachment-large size-large wp-post-image" height="447" src="https://hackaday.com/wp-content/uploads/2026/01/shortest_path_PCB_frequency_vs_impedence_electrarc240_youtube.jpg?w=800" style="margin: 0 auto; margin-bottom: 15px;" width="800" /></div><p>Everyone knows that the path of least resistance is the path that will always be taken, be it by water, electricity or the feet of humans. This is where the PCB presented by [ElectrArc240] on YouTube <a href="https://www.youtube.com/watch?v=Fg86BXGWvJQ" target="_blank">is rather confusing</a>, as it demonstrates two similarly sized traces, one of which is much shorter than the other, yet the current opts to travel via the much longer trace. If you were to measure this PCB between each path, the shorter path has the lowest resistance at 0.44 Ω while the longer path is 1.44 Ω. Did the laws of physics break down here?</p>
<p>Of course, this is just a trick question, as the effective resistance for an electrical circuit isn’t just about ohmic resistance. Instead the relevant phrasing here is ‘path of least <a href="https://en.wikipedia.org/wiki/Electrical_impedance" target="_blank">impedance</a>‘, which is excellently demonstrated here using this PCB. Note that its return path sneaks on the back side along the same path as the long path on the front. To this is added a 1 MHz high current source that demonstrates the impact of alternating current, with reactance combining with the resistance.</

@ThinkingSapien
It's a Smith Chart.
https://en.wikipedia.org/wiki/Smith_chart
#TransmissionLines #radio #electronics #impedance

8-channel high-speed #OpenSource #electrical #impedance #tomography device implemented on a programmable #system-on-a-chip:

#EIT is a non-invasive #imaging technique providing info about the internal #conductivity distribution of a body/object

https://doi.org/10.1016/j.ohx.2025.e00667
#DIYbio #lab #instruments #SoC

#PocketPotentiostat: #OpenSource framework for a #potentiostat, #galvanostat & #electrochemical #impedance #spectrometer:

- #voltammetry & #chronoamperometry (pA-0.1 A & ±12 V)
- #chronopotentiometry
- #EIS bandwidth: 0.1-1 MHz

https://doi.org/10.1021/acs.jchemed.1c00228
#DIYbio #electrochemistry #lab #instruments #science #research #STEM #MINT #education

I think I'm finally starting to understand the reactance part of #impedance . You can increase the reactance by adding an inductor (X = jωL; ω = 2πf) and lower it by adding a capacitor (X = 1/(jωC)). You can use networks of variable capacitors and inductors if you want to adjust that (which affects SWR) while transmitting at the frequencies you want. :3c

And once you're done, you can replace those with fixed capacitors and inductors because you'll know what works! :D

#AmateurRadio #HamRadio

I think I'm finally starting to understand the reactance part of #impedance . You can increase the reactance by adding an inductor (X = jωL; ω = 2πf) and lower it by adding a capacitor (X = 1/(jωC)). You can use networks of variable capacitors and inductors if you want to adjust that (which affects SWR) while transmitting at the frequencies you want. :blobfoxthinkgoogly:

And once you're done, you can replace those with fixed capacitors and inductors because you'll know what works! :blobfox3c:

#AmateurRadio #HamRadio

How to slap that pesky impedance into compliance...

#SmithChart #Impedance #TransmissionLine

Coax Stub Filters Demystified https://hackaday.com/2024/07/21/coax-stub-filters-demystified/ #amateurradio #RadioHacks #impedance #bandpass #matching #coaxial #filter #stub #ham #RF

And you thought we had it bad with impedance matching...

https://howelectrical.com/static-var-compensator/

https://electricalbaba.com/statcom-working-principle-design-and-application/

#HamRadio #AmateurRadio #impedance #PowerTransmission

ABI EIT: A wearable #OpenSource electrical #impedance #tomography (#EIT) device:

-#medical #imaging
-monitoring #lung/#cardiac function, #brain activity
-cost: ~US$260
-#3Dprinted parts
-#Teensy controller

https://doi.org/10.1016/j.ohx.2024.e00521
#DIYbio #lab #instruments #medicine #diagnostics

Ground Loop Isolator, Hum Eliminator, with Variable Impedance (full specs in the first comment)
#groundloop #groundloopisolator #groundloophum #humeliminator #dpFXpedals #dpFX #boutiquepedals #handmadepedals #handmadeeffects #pedalsandeffects #effectspedals #guitarpedals #basspedals #pedaleffects #isolatorpedal #isolator #isolationtransformer #variableimpedance #impedance #handpainted #handpaintedpedals

Hmmm. I guess the structure of posts on here doesn't let us tag a reblog/boost with our own tags, since it is just the parent post being boosted. Closest would be a blank add on post... [#Tumblr](/tags/Tumblr) [#Goblin](/tags/Goblin) [#ActivityPub](/tags/ActivityPub) [#impedance mismatch](/tags/impedance mismatch)

Pour la première fois de ma vie quelqu'un réussit à me faire comprendre l'impédance.

What does "impedance matching" actually look like? (electricity waves)
https://youtube.com/watch?v=RkAF3X6cJa4

#ElectricalEngineering #AlphaPhoenix #Impedance #ImpedanceMatching

Homebrew TEM Cell Lets You EMC Test Your Own Devices https://hackaday.com/2023/11/02/homebrew-tem-cell-lets-you-emc-test-your-own-devices/ #lineimpedancestabilizationnetwork #electromagneticcompatibility #transvereelectromagneticcell #spactrumanalyzer #ToolHacks #impedance #testing #copper #LISN #emc #fr4 #TEM

When Does Impedance Matching a PCB Trace Become Unavoidable? https://hackaday.com/2023/08/27/when-does-impedance-matching-a-pcb-trace-become-unavoidable/ #impedancematching #PCBrouting #impedance #hardware #Science #route #pcb

The Dipole Antenna Isn’t as Simple as it Appears https://hackaday.com/2023/08/16/the-dipole-antenna-isnt-as-simple-as-it-appears/ #RadioHacks #wavelength #bandwidth #frequency #impedance #resistive #Reactive #antenna #dipole #vna

Meh. What's the #impedance of a #RaspberryPi #GPIO pin in input mode? Is it safe for a high value from another pin in output mode to sink directly to it?

I haven't found this discussed anywhere. It 𝘭𝘰𝘰𝘬𝘴 as though a pin in input mode has quite a high 𝑍 and sinks very little current, but I don't want to experiment just in case that's an invalid conclusion. 😔🤔

In an other life I did a lot of #RF Radio Frequency work. Transmission line principles were bread and butter.

This #article explains a lot in a small space. Recommended.

https://www.allaboutcircuits.com/technical-articles/introduction-to-impedance-matching-using-transmission-line-elements/

It makes use of a #SmithChart, one of the cleverest bits of maths I know. There is a link on the page I gave that jumps to an equally good explantation of smith charts.

#Electronics #Mathematics #Impedance #Radio #RadioTheory #Calculation

#Impedance

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