This presentation should be incorporated into the initial training of anyone wishing to get their ham license. I found the information to be concise, articulated well, sufficiently illustrated, and no needless fluff. Anyone actively interested in the topic will be well served with this introduction into the concepts discussed. Thank you for uploading this video; I only wished that I had seen it much sooner!
What a wonderfully executed overview of HF propagation. I wish I had seen this video while studying for my General license. Clear, concise and pure gold.
Anyone who is seriously interested in the subject will benefit from this introduction to the concepts covered. The information is articulated and illustrated clearly. Doron, 4X4XM
Really good presentation 👏🏼 so kind of R&S to set up this videos of how radio and some antennas works. Sended this video to some friends that are interested in radio 💪🏼 Best 73/ Roger
Thanks! In addition to test and measurement instruments, we also design and manufacture HF radios, amplifiers, antennas, etc. (although mostly for the commercial and military / government markets, not really for amateurs). Thanks again for the feedback! 73, Paul KO4LZ
Visual observation. There are actually some manuscripts from that time that show sunspots being recorded (see image at link below, from the year 1611). Not sure that they followed the modern precautions /warning regarding looking at the sun. :) Thanks! images.skinnerinc.com/full/920/1217920_view%2016_16.jpg
HF can be (and regularly is) used to communicate between any two points on the globe, so maximum range is half the Earth's circumference :) In practice, the maximum achievable distance is function of many factors, including the current state of the ionosphere, the chosen frequency, the Tx and RX antenna characteristics and orientation, the Tx power, the Rx sensitivity, noise levels, modulation type, etc. During peaks in the 11 year solar cycle, worldwide communication can often be accomplished with less than a watt of power and a very modest antenna, whereas at the "troughs," it can be very challenging to reach certain stations without very high power levels and very good antennas.
@@pauldenisowski slightly more than half as the RF horizon is more than visual horizon. Radio waves bend. Plus multi hop and long path happen daily. Many factors can give more range than just half. WW5RM
@@WW5RM Yes, of course. :) Long-path is an excellent example of where the total path length will be longer than the "short part" to the destination: There are many occasions where or reasons why long-path may be the best way to reach a given station. And as you also point out, the actual path length will depends on the number of hops, etc. I interpreted the question to be: "what is the max possible distance between transmitter and receiver when using HF?" and since HF does allow (under the right conditions) communications between any two points on the globe, my somewhat tongue-in-cheek answer was "half the Earth's circumference" :) Thanks for pointing out that the actual max propagation distance can be considerably longer. 73!
One of my students pointed out that the statement at 10:43 says that when the RF passes through the ionosphere and into space, that is the critical frequency. However, all the textbooks I have say the critical frequency is the highest frequency that is reflected (refracted) back to ground. Is there another definition in use?
That's a great question. I suppose you could avoid ambiguity by defining it as the frequency above which signals pass into space and below which signals are refracted back (laughs).
Critical frequency is the highest magnitude of frequency above which the waves penetrate the ionosphere and below which the waves are reflected back from the ionosphere. It is denoted by "fc". Its value is not fixed and it depends upon the electron density of the ionosphere.
the picture depicts lines of electromagnetic force but they tend to make our mins believe the signals are shot out like bullets,but its really a giant omni directionals disruption of molecules from the antenna envoping in an omni directional patteren like a bomb going off,the molecule stays put but transfers the vibration to the nieghboring molecule like dominoes,f going deep into the ground and reflecting back upwards or refracting from the ground becuase of the different meduim opposedt to the atmosphere then reaching up into the inonsphere where it then refracts back to earth where it could end up anywhere there is a least resistant path to do so ,i think anyway ,every time we hit the key we ignite a giant vibration of the molecules like a pattern of an explosion ,with everything staying put
This presentation should be incorporated into the initial training of anyone wishing to get their ham license. I found the information to be concise, articulated well, sufficiently illustrated, and no needless fluff. Anyone actively interested in the topic will be well served with this introduction into the concepts discussed. Thank you for uploading this video; I only wished that I had seen it much sooner!
Thank you!
Yes but at a much lower speed.
No matter which ham radio class you are and how much experience you have this video should be listened many times.
Wow, it's really good. It's very attractive and the AD is very interesting
What a wonderfully executed overview of HF propagation. I wish I had seen this video while studying for my General license. Clear, concise and pure gold.
after 44 years of HF ops it still makes me feel like a child when i get long DX,what a great feeling
Anyone who is seriously interested in the subject will benefit from this introduction to the concepts covered. The information is articulated and illustrated clearly.
Doron, 4X4XM
Thank you for the feedback!
This is an absolutely excellent explanation and presentation. THANK YOU!
Thank you for the feedback!
Excellent presentation. Clear and to the point. The details of HF propagation can get quite complicated but this introduction is spot on.
Thank you!
Very nicely described.refrashed my knowledge of hf prepogation
Thank you!
Great presentation!
Thank you kindly
"HF the only way to fly" regards from vk3 and remember "when triodes are glowing electrons are flowing"
I luckily trained from R&S Germany
Good Presentation
Great video, thank you🇺🇸
Thank you for watching!
Excellent presentation with simple, effective graphics. Thanks
Thanks for the feedback!
Good English presentation...
Thanks - it's my native language :)
Wow. Great presentation. It covers a lot of ground. I’m gonna have to listen to it again. Thank you!
Excellent presentation! This is perfect for my new ham friends, thank you!
Amazing presentation, thank you!
Thanks!
You're the best 👍👏👏👏
Very Good !
Great video
Really good presentation 👏🏼 so kind of R&S to set up this videos of how radio and some antennas works. Sended this video to some friends that are interested in radio 💪🏼
Best 73/ Roger
Thanks! In addition to test and measurement instruments, we also design and manufacture HF radios, amplifiers, antennas, etc. (although mostly for the commercial and military / government markets, not really for amateurs). Thanks again for the feedback! 73, Paul KO4LZ
@@pauldenisowski Nice to hear 😀 I have the privilege to use some R&S instruments in my work 👍🏻 de Sa1ckr
Excellent presentation
Excellent
Great explanation 🥳
It is informative indeed... Thanks...
How was sun spot info collected 400 years ago?
Thanks for the awesome video. Learnt a lot.
🙏
Visual observation. There are actually some manuscripts from that time that show sunspots being recorded (see image at link below, from the year 1611). Not sure that they followed the modern precautions /warning regarding looking at the sun. :) Thanks!
images.skinnerinc.com/full/920/1217920_view%2016_16.jpg
@@pauldenisowski Damn that is interesting!!! Thank you so much!!!
Well done.
How do you prevent HF signals.
In maximum condition, how must the most longer distance range for communication in HF frequency?
HF can be (and regularly is) used to communicate between any two points on the globe, so maximum range is half the Earth's circumference :) In practice, the maximum achievable distance is function of many factors, including the current state of the ionosphere, the chosen frequency, the Tx and RX antenna characteristics and orientation, the Tx power, the Rx sensitivity, noise levels, modulation type, etc. During peaks in the 11 year solar cycle, worldwide communication can often be accomplished with less than a watt of power and a very modest antenna, whereas at the "troughs," it can be very challenging to reach certain stations without very high power levels and very good antennas.
@@pauldenisowski slightly more than half as the RF horizon is more than visual horizon. Radio waves bend. Plus multi hop and long path happen daily. Many factors can give more range than just half.
WW5RM
My furthest QSO is 9100 miles / 14,650 km.
Jan - ZS6HA in South Africa.
I am in Texas.
WW5RM
@@WW5RM Yes, of course. :) Long-path is an excellent example of where the total path length will be longer than the "short part" to the destination: There are many occasions where or reasons why long-path may be the best way to reach a given station. And as you also point out, the actual path length will depends on the number of hops, etc.
I interpreted the question to be: "what is the max possible distance between transmitter and receiver when using HF?" and since HF does allow (under the right conditions) communications between any two points on the globe, my somewhat tongue-in-cheek answer was "half the Earth's circumference" :) Thanks for pointing out that the actual max propagation distance can be considerably longer. 73!
@@WW5RM Impressive! The long path between EM23 and KG53 would be about 15,800 miles :)
One of my students pointed out that the statement at 10:43 says that when the RF passes through the ionosphere and into space, that is the critical frequency. However, all the textbooks I have say the critical frequency is the highest frequency that is reflected (refracted) back to ground. Is there another definition in use?
That's a great question. I suppose you could avoid ambiguity by defining it as the frequency above which signals pass into space and below which signals are refracted back (laughs).
Critical frequency is the highest magnitude of frequency above which the waves penetrate the ionosphere and below which the waves are reflected back from the ionosphere. It is denoted by "fc". Its value is not fixed and it depends upon the electron density of the ionosphere.
@@tixilx that was my understanding too.
question about slide 23. you stated if the MUF becomes higher than the LUF @17:38. did you mean if the LUF becomes higher than the MUF??
I was wonder the same because “
Thanks for a great presentation! Will pass along to other ham operators. N5CSU
Hi Rich,
thanks for the recommendation.
Thanks Rich! 73 de Paul, KO4LZ
Anda boleh memilih untuk salah satu daripada hadiah di atas
Pemberian ilmu adalah anugerah terhebat :)
Hernandez Shirley Smith Cynthia Perez William
Giggity giggity Recon
Garcia Brian Anderson Sharon Miller Richard
Send this to people who think the earth is flat. Prepare to be amazed by their ignorant defiance.
If the world were flat, there would be no long-path propagation :)
Thad Spring
Miller Joseph Williams Barbara Gonzalez Donald
Tessie Crossroad
Nikolaus Lodge
I wonder if there are any flat Earth radio people out there...
Moshe Gardens
Libbie Summit
the picture depicts lines of electromagnetic force but they tend to make our mins believe the signals are shot out like bullets,but its really a giant omni directionals disruption of molecules from the antenna envoping in an omni directional patteren like a bomb going off,the molecule stays put but transfers the vibration to the nieghboring molecule like dominoes,f going deep into the ground and reflecting back upwards or refracting from the ground becuase of the different meduim opposedt to the atmosphere then reaching up into the inonsphere where it then refracts back to earth where it could end up anywhere there is a least resistant path to do so ,i think anyway ,every time we hit the key we ignite a giant vibration of the molecules like a pattern of an explosion ,with everything staying put
Maybe you should make a video to share this particular vision of how things work. The words are not quite enough.
Hall Daniel Lopez Sandra White Margaret
Von Station
Wow, it's really good. It's very attractive and the AD is very interesting
Wow, it's really good. It's very attractive and the AD is very interesting
Wow, it's really good. It's very attractive and the AD is very interesting
Wow, it's really good. It's very attractive and the AD is very interesting