If two waves of the same frequency align with each others' valleys, they align with each others' peaks. Do you mean they should be aligned peak to valley? I don't know how you're deciding which direction of the axes is positive and which is negative though.
Edit: neither of us are right, EM waves in vacuum do travel in phase but in conductors, there is a phase difference between 0° (very high resistance) and 45° (superconductor). So yeah, EM waves can "tell" they're in a dummy load.
Well it's wrong. I suppose you are thinking so because Maxwell's equations shows B depending on (∆E/∆t)[i cant write \partial symbol], BUT remember LHS is not B but is curl(B) so derivative acts on both sides. So they are in phase and not 90° out of phase. So the peaks should align, atleast in free space
They wish they were in an antenna and going out as radio waves, but instead they’re in a dummy load and not going anywhere. 50ohm is a common antenna impedance.
i might be wrong here but i think a dummy load is different from a terminator, they both 50 ohm, but a terminator is more like a connector cap, while a dummy load is designed to dissipate heat and can often take many watts of power over extended time without starting glow
That's my understanding as well. I've seen dummy loads used when testing transmitters at power so that nothing gets too hot. They usually have a big aluminum heat sink.
16 Comments
marcos@lemmy.world · 34 pts · 214d
Just to point out, because it's bothering me way more than it should...
But the electric and magnetic peaks align with each other's valleys, not with each other's peaks.
FishFace@piefed.social · 9 pts · 213d
If two waves of the same frequency align with each others' valleys, they align with each others' peaks. Do you mean they should be aligned peak to valley? I don't know how you're deciding which direction of the axes is positive and which is negative though.
ChaoticNeutralCzech@feddit.org · 1 pts · 213d
FishFace@piefed.social · 3 pts · 213d
Uh, no?
ChaoticNeutralCzech@feddit.org · 4 pts · 212d
No, they fucking shouldn't
https://en.wikipedia.org/wiki/Maxwell%27s_equations#Vacuum_equations,_electromagnetic_waves_and_speed_of_light
Edit: neither of us are right, EM waves in vacuum do travel in phase but in conductors, there is a phase difference between 0° (very high resistance) and 45° (superconductor). So yeah, EM waves can "tell" they're in a dummy load.
captainlezbian@lemmy.world · 2 pts · 213d
Yeah, because it's not pulsing in intensity, it's pulsing between which kind of energy it's being
mexicancartel@lemmy.dbzer0.com · 1 pts · 211d
Well it's wrong. I suppose you are thinking so because Maxwell's equations shows B depending on (∆E/∆t)[i cant write \partial symbol], BUT remember LHS is not B but is curl(B) so derivative acts on both sides. So they are in phase and not 90° out of phase. So the peaks should align, atleast in free space
tate@lemmy.sdf.org · 0 pts · 213d
You're describing circular polarization. It's not the only way.
Techlos@lemmy.dbzer0.com · 0 pts · 213d
Maybe it's showing polarization superpositions of the E-field?
Remember_the_tooth@lemmy.world · 15 pts · 214d
I get the reference to the original meme. I don't understand the EM spectrum component, though.
deranger@sh.itjust.works · 32 pts · 214d
They wish they were in an antenna and going out as radio waves, but instead they’re in a dummy load and not going anywhere. 50ohm is a common antenna impedance.
Remember_the_tooth@lemmy.world · 13 pts · 214d
Thanks. That puts me on the right track.
https://www.onallbands.com/ham-radio-101-dummy-loads-smart-idea/
hedgehogging_the_bed@lemmy.world · 8 pts · 214d
Had to go get my radio-tech spouse. His reply "Oh, that's the dumb name for a terminator...."
Apparently "dummy load" isn't what they call them in the USAF
einfach_orangensaft@sh.itjust.works · 6 pts · 213d
i might be wrong here but i think a dummy load is different from a terminator, they both 50 ohm, but a terminator is more like a connector cap, while a dummy load is designed to dissipate heat and can often take many watts of power over extended time without starting glow
Eranziel@lemmy.world · 1 pts · 213d
That's my understanding as well. I've seen dummy loads used when testing transmitters at power so that nothing gets too hot. They usually have a big aluminum heat sink.
BillyClark@piefed.social · 5 pts · 214d
They can't wait anyways because they do not experience the passage of time.
JackbyDev@programming.dev · 2 pts · 212d
My reaction while reading this.