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Thanks for the comment. (1) J = dI/dA = rho*v. (2) the analysis shown assumes only a snapshot in time which is why e*ikr is used without the eˆ-iwt part. I agree that it's not the complete expression since we're missing time dependence but it suffices to show the spatial character of the wave.

@@quantumradio Your videos are like a piece of art. That's why I come back to them. I don't want to criticize you, just add something. Thanks!

@@jacobvandijk6525 Of course. No offense taken. I sincerely appreciate your comments and insight. Have a good one!

Thanks for the comment. Actually the Quantum part in the title was intended to allude to physics. The second part, radio, was of course referring to E&M since the original videos I recorded were about E&M radiation. I currently don't anticipate making any videos dealing with photons, the gauge bosons responsible for the E&M force.

@@quantumradio And the word "Quantum" sells better, right? Haha.

@@jacobvandijk6525 Quantum is indeed a term you hear often. I'm reminded of a lecture by John A. Wheeler that I attended as an undergrad in which he said that he'd preferred "hunk" mechanics as opposed to quantum since it conveys a similar idea. So yea maybe "Quantum" was better. :) BTW, I've not monetized the TH-cam channel & I only publish material that I believe is interesting. Hopefully some of it is helpful to you.

@@quantumradio I think many students can profit from your neat site. It helped me, yes (but I'm not a regular student; studying physics for fun).

What you said + Me

Thanks for the comment. Yes, I'm running 2.00x now and WSJT-X worked fine with it. Best of luck & 73!

Thank you for the comment. Hope the derivation was helpful.

@@quantumradio Absolutely. From the book I wasn't so sure I got things right. But now I have. Thanks for the confirmation.

Thank you for the comment. The (tr)uSDX is my one and only POTA rig now a days and works great on CW mode. I've taken it to state parks in my area and even activated (CW) a park in England with it. I'm sure there are better, & more expensive, portable radios out there but I'm quite satisfied with it. As far as a recommendation, I hesitate a bit and would prefer to only share my experiences with the radio since we each have favorites and different criteria. I like its low current draw (˜50mA on Rx and ˜500mA on Tx), portability, versatility (CW and SSB modes), and low price (US$149 on Amazon). I hope that helps & 73!

Thank you for the suggestion. I've created the "Antenna Physics" playlist w/only the antenna videos in it. Plus the numerical integration in Python for the HalfWave Dipole antenna. Best of luck in your studies.

@@quantumradio Exactly what I hoped for. Thank you very much!

Thank you for the comment. I've heard a similar comparative audio report from another Ham radio operator. I tend to like the way both radios sound, though that's my personal view. 73!

Thanks for the toughtful comment. The way I look at it, the coax sheath is my counterpoise in the simulation. MMANA GAL doesn't consider an impedance transformation for the counterpoise, it does an impedance transformation from the feedpoint to the antenna element. The counterpoise is the ground wire, coax sheath really, connecting the ground on the transformer to my floating ground of my transceiver. I could probably fiddle more with the counterpoise in this model but I found that this simulation gave the insight that I needed to build the EFHW antenna and start testing it. I didn't model the capacitor as a load in my simulation. However, to your point, I have seen reports that the high frequencies are helped by using the capacitor but my model doesn't include this effect. Yes, I have built, tested, and folded (not cut) my antenna element to resonate on 40m, 20m, 15m. The EFHW antenna I built last year at field day is pretty much what I modeled here and it's the one that I take on POTA outings now a days. It's very portable and you can drape it over a tree branch, or use a fiberglass pole to hold up the antenna element end. This makes for a quick setup. Hope that answers the doubts. 73!

Thanks for the comment. It sounds like the version of AVRDUDESS that you're working with may be the issue. I used version 2.14 in the video so you may want to try loading an older version of that software. Best of luck & 73.

@@quantumradio thanks I think the AVRUDUDESS versions must be different now. I deleted off my computer and reloaded and I finally got it to work Thanks for the help

NM...LDO..I had the js8 slider all the way lowered.

Thanks for the comment. I used velcro tape to hold the head unit in place in the center console at the time that I made this video; however, I now have the head unit in a cubby hole left of the steering wheel. I used velcro to secure the head unit in the cubby hole also. Hope that helps. 73.

Thank you for the comment. At 8:54 when NR2 is enabled it cleaned up the signal pretty good. I then unlicked NR2 at 8:58 and the noise came back. I enabled NR2 again at 9:07 and the noise went away, again. I then clicked on SNB at 9:14 and the signal became sharper in the higher frequencies and clearer. At 9:22 I enabled ANF and the signal was mostly unaffected since no Noise filters had been previously configured on this window.

Thank you for the comment. Unfortunately I've not modeled that antenna; however, I believe that you'd go into Edit>Wire Edit>XY, XZ, and YZ in MMANA GAL and draw out the segments. Best of luck with your project & 73.

Nermin, unfortunately I don't produce charts.

@@quantumradio ok

Gracias por el comentario. Si ud. se refiere al término bˆ2*N que se escribe en el minuto 8:58, el N sale pues la suma sin ningun termino con indice es equivalente a la suma sobre todo valor de i. Es decir, suma sobre i desde i=0 a i=N es igual a N. Entonces ese N multiplica a la constante que sacamos y pusimos al frente de la suma, bˆ2. Ojalá que eso sea mas claro. Saludos.

Hello. Unfortunately I don't know the answer to that question. I keep my projects in Github so I don't have to have a local source safe. I have working directories in my laptop or MAC which I clone from the main Github repository but in my workflow I really want to minimize having multiple copies of code due to security and versioning issues. My local copies are really working copies that get nuked after uploading to the mothership in Github. Best of luck in your project.

@@quantumradio I realized that my question was a little ambiguous so I've edited to say "private GitHub repository." You may have GitHub repos that are "private" meaning that you set the access controls on who can use the repo. Have you used Cloud 9 on such a repo or are all of your repos open to the public?

@@quantumradio Thanks for the reply!

Thank you for the comment.

Thank you for the comment. Unfortunately I'm not tracking your question. If you can point the time mark where the confusion is, I may be able to help.

Thanks for the comment. My setup didn't require the Digirig, just a sinigle USB cable from (tr)uSDX to the Windows laptop. I have heard of folks having good luck with the Digirig. It may be that the Digirig connection is more reliable than the single USB cable I've used; however, I don't have first hand experience of the Digirig connection to compare. Best of luck and 73!

Thank you for the comment. I'm glad that this was helpful. What I understood that the math was saying didn't make sense initially but after looking more carefully into it, and considering the r-squared factor, the math was of course correct. Best of luck in your QM journey, it WILL be worth it!

Thanks for the comment. No need to apologize at all. You are 100% correct, the sound in this video is terrible. It was one of my first ones and I didn’t have an external mic on the laptop. So what you hear is the built in mic in my old laptop. Either way thx for the feedback & I will remake the video in the near future since the MMANA GAL program continues to be very useful to many hams. 73.

Thank you for the comment and best of luck in your projects!

Thank you for the comment. Yes, in my opinion the (tr)uSDX is good for learning CW. It lets you pick a straight key or an “Iambic” key which is a fancy word for paddles. If you pick Iambic key you can then select the speed for the key, e.g. 15 WPM. You can then set transmission power to zero and use the (tr)uSDX as a practice oscillator.

Thanks for the comment. There is a version pre-loaded in the raspberry pi inside the Anan G-2 called piHPSDR that runs on debian; however, it's got a lot less bells and whistles compared to Windows Thetis. Best of luck & 73!

Thanks for the comment and glad it was helpful. Best of luck with all your projects & 73!

Piensa que es problema de Software o de Hardware? es decir, todo los seteos del Winlink>VARA estan bien? Porque si logra que el FT8 funcione, esta ya casi a la meta con Winlink. Solo restan pocos seteos adicionales para que el Winlink trabaje. 73!

@@quantumradio Hola Quantum, gracias por tu atención. Creo que el problema es "operador"... 😄 Winlink y VARA están bien, pero no encuentro la manera de establecer una conexión entre la radio y la aplicación. De hecho, al intentar configurar, se leyó el modo VOX, que uso en FT8.

@@jorgepu2lqx400Jorge, suerte con tu "troubleshooting". Ojo con la version de firmware para el (tr)uSDX. Yo creo que usé la version de software/firmware = 2.00u y esto se puede verificar con la opcion de menu 9.7. 73!

@@quantumradio Thank you, so be it. Good weekend!

It sounds like you're talking about the needle on the signal meter at the bottom left of the VARA window showing red and not coming down to yellow or green. I'd suggest lowering the volume in the (tr)uSDX to 4 or 5. 73.

Thank you for the comment. Yes, the Thetis software is amazing. The noise reduction "2" is a particularly good algorithm for noise reduction. Best of luck and 73!

Agreed. I just tried Diversity reception w/the G2. The tech in Thetis coupled with the amazing G2 hardware really are fascinating. Still learning, 73!

Que bien. Gracias por el comentario y suerte con su proyecto. Saludos!

Thank you for the comment. I love the IC 7300 so it's difficult for me to say that the ANAN G-2 is now my favorite shack transceiver. They're both fine rigs but the signal processing in the G-2 blows my hair back. It's sort of like listening to FM radio when you click on the "NR2" noise reduction. 73!

Thank you for the comment. Yes, my video was not an in-depth test rather it was my observation from a "typical user" perspective. The IC 7300 for sure is a great rig with many noise processing options. Best of luck & 73!

David, pienso que no es recomendado con baterías de la misma marca y aun peor de 2 marcas distintas. Lo digo pues las baterías deben de cargar y descargar uniformemente o se crea una corriente entre las mismas dada la diferencia de voltages. Si las baterías son de diferentes edades o los BMSs (Battery Management Systems) tienen problemas, etc. Recomiendo leer el MSDS (Material Safety Data Sheet) de cada batería a ver si es recomendado o no por el manufacturador. Saludos.

Thanks for the comment. The way I understand it, special relativity (SR) may be the bigger concern since General relativity (GR) would require large masses to affect the curvature of space-time; however, SR kicks in at high enough velocities so it could affect us. Recall that the assumption in the derivation is that r=ct >> ut so the lurch is a lot slower than the speed of light. So we should be OK to neglect SR. 73!

@@quantumradio i think it violates the equivalence principle. a charge thats is gravitaionally accelarated should radiate but then a co-accelareted observer should be able to observe the radiation - and by that be able to tell free fall from weightlessness

@@kasel1979krettnach Andreas, the equivalence principle refers to the equivalence of gravitational and inertial mass. In this case gravitational acceleration plays no part. Best of luck in your studies.

I was referring to that elevator thought experiment. try falling alongside an electric charge and you have a way to determine whether you are free falling or in free space. charge radiates --> free falling (acceleration), does not radiate = free space. My studies are long past. @@quantumradio

Most welcome!

Thank you for the comment and glad it was helpful, 73!

CW is not easy and requires persistence in my opinion; however, you do get better and this makes for a great sense of accomplishment. Even 10wpm with little farsnsworth is tough. It doesn't give the brain a chance to rest. 73.

Thanks for the comment. Sounds like a good plan. I got the IC 7300 as my first HF rig and then, as I got more into POTA, invested in the Xiegu G90. Both are fine transceivers. Best of luck in the hobby & 73!

Thank you for the comment and I believe that you are correct. I think that the line from the "Q5" label in the diagram to the Collector shouldn't be there.

You're referring to JS8Call from what I can tell. I'd say get the latest version of that SW and see if that fixes it. Best of luck & 73.

@@quantumradio yes I was, I installed it this morning. Pretty sure it's the latest

@@justawfulgamer7738 JS8Call version 2.2.0. Try clicking on Menu>Mode>Enable HB & Enable ACK. That should do it.

Thanks for the comment. The Winlink & VARA software & service is free though I paid for the "VARA license" & can in theory send/receive at faster transmission rates than w/the free version. As far as Winlink is concerned, I believe that you do have to have a callsign & signup to use Winlink, though I could be wrong. I have a Winlink account but not sure if it's required. Good news is that you can send/receive your emails to/from any email address, e.g. wxyz@gmail.com, abcd@outlook.com, etc. Hope that helps, 73!

@@quantumradio I got it working. Pretty cool stuff! Thanks

Thank you for the comment. Yes, you can do it! Best of luck & 73!