Understanding HF Propagation

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  • เผยแพร่เมื่อ 4 ม.ค. 2025

ความคิดเห็น • 85

  • @BryanWicks
    @BryanWicks ปีที่แล้ว +30

    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!

    • @pauldenisowski
      @pauldenisowski ปีที่แล้ว +2

      Thank you!

    • @y_x2
      @y_x2 8 หลายเดือนก่อน

      Yes but at a much lower speed.

  • @TheTechPrepper
    @TheTechPrepper 3 ปีที่แล้ว +24

    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.

  • @solarmfolijezastakla
    @solarmfolijezastakla 2 ปีที่แล้ว +9

    No matter which ham radio class you are and how much experience you have this video should be listened many times.

  • @outwithradios8145
    @outwithradios8145 4 ปีที่แล้ว +19

    after 44 years of HF ops it still makes me feel like a child when i get long DX,what a great feeling

  • @redsky1433
    @redsky1433 2 ปีที่แล้ว +5

    Excellent presentation. Clear and to the point. The details of HF propagation can get quite complicated but this introduction is spot on.

  • @DoronTirkel
    @DoronTirkel ปีที่แล้ว +5

    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

  • @elmoreglidingclub3030
    @elmoreglidingclub3030 4 หลายเดือนก่อน +1

    This is an absolutely excellent explanation and presentation. THANK YOU!

    • @pauldenisowski
      @pauldenisowski 2 หลายเดือนก่อน +1

      Thank you for the feedback!

  • @TylerWilson-f9t
    @TylerWilson-f9t 6 หลายเดือนก่อน +1

    Wow, it's really good. It's very attractive and the AD is very interesting

  • @gbisaga
    @gbisaga 19 วันที่ผ่านมา

    I agree with the other folks, if you are studying for a FCC ham exam, especially the General or Extra exam, you should watch this video. Good concise description that will supplement your other learning.

  • @chrismeagher7237
    @chrismeagher7237 3 ปีที่แล้ว +2

    Excellent presentation with simple, effective graphics. Thanks

  • @garylanders1470
    @garylanders1470 2 ปีที่แล้ว +2

    Great presentation!
    Thank you kindly

  • @lpark8
    @lpark8 4 ปีที่แล้ว +2

    Wow. Great presentation. It covers a lot of ground. I’m gonna have to listen to it again. Thank you!

  • @Ambatukamhorifooq
    @Ambatukamhorifooq 2 ปีที่แล้ว +2

    Amazing presentation, thank you!

  • @victorb22622
    @victorb22622 ปีที่แล้ว +1

    Very nicely described.refrashed my knowledge of hf prepogation

  • @konnorkuznetsov1035
    @konnorkuznetsov1035 4 ปีที่แล้ว +7

    Excellent presentation! This is perfect for my new ham friends, thank you!

  • @rfmonkey4942
    @rfmonkey4942 4 ปีที่แล้ว +5

    "HF the only way to fly" regards from vk3 and remember "when triodes are glowing electrons are flowing"

  • @jamespruitt1046
    @jamespruitt1046 หลายเดือนก่อน

    Does the day vs. night rule apply to the time of day for the location of the receive / transmit antennas or the location of the person you're trying to communicate with? Meaning if my antenna is in Hawaii and it's morning, but I'm trying to communicate with someone in Guam, would I use a frequency based on the time in Guam or the time in Hawaii?

  • @GraceKataliko
    @GraceKataliko 6 หลายเดือนก่อน +1

    You're the best 👍👏👏👏

  • @Brigantine2008
    @Brigantine2008 4 หลายเดือนก่อน +1

    Great video, thank you🇺🇸

    • @pauldenisowski
      @pauldenisowski 2 หลายเดือนก่อน

      Thank you for watching!

  • @m_rehanbutt
    @m_rehanbutt 2 ปีที่แล้ว +2

    Good Presentation

  • @m_rehanbutt
    @m_rehanbutt 2 ปีที่แล้ว +3

    I luckily trained from R&S Germany

  • @muhammadsoleh9148
    @muhammadsoleh9148 2 ปีที่แล้ว +1

    Good English presentation...

    • @pauldenisowski
      @pauldenisowski ปีที่แล้ว

      Thanks - it's my native language :)

  • @boim9312
    @boim9312 2 ปีที่แล้ว +1

    Great explanation 🥳

  • @RogerBravo12
    @RogerBravo12 2 ปีที่แล้ว +1

    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

    • @pauldenisowski
      @pauldenisowski 2 ปีที่แล้ว +1

      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

    • @RogerBravo12
      @RogerBravo12 ปีที่แล้ว +1

      @@pauldenisowski Nice to hear 😀 I have the privilege to use some R&S instruments in my work 👍🏻 de Sa1ckr

  • @skydivingcomrade1648
    @skydivingcomrade1648 2 ปีที่แล้ว +1

    Great video

  • @philsimpson6093
    @philsimpson6093 3 ปีที่แล้ว +1

    Excellent presentation

  • @drankurbaruah
    @drankurbaruah 3 ปีที่แล้ว +1

    How was sun spot info collected 400 years ago?
    Thanks for the awesome video. Learnt a lot.
    🙏

    • @pauldenisowski
      @pauldenisowski 3 ปีที่แล้ว +5

      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

    • @drankurbaruah
      @drankurbaruah 3 ปีที่แล้ว +1

      @@pauldenisowski Damn that is interesting!!! Thank you so much!!!

  • @G0FUW
    @G0FUW 3 ปีที่แล้ว

    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?

    • @pauldenisowski
      @pauldenisowski 3 ปีที่แล้ว +2

      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).

    • @tixilx
      @tixilx 3 ปีที่แล้ว +3

      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.

    • @G0FUW
      @G0FUW 3 ปีที่แล้ว +1

      @@tixilx that was my understanding too.

  • @philmonat9352
    @philmonat9352 7 หลายเดือนก่อน +1

    Very Good !

  • @bijohnAdams
    @bijohnAdams 3 ปีที่แล้ว +1

    It is informative indeed... Thanks...

  • @elkierose6228
    @elkierose6228 ปีที่แล้ว

    How do you prevent HF signals.

  • @kartiniganesha6741
    @kartiniganesha6741 4 ปีที่แล้ว +1

    In maximum condition, how must the most longer distance range for communication in HF frequency?

    • @pauldenisowski
      @pauldenisowski 4 ปีที่แล้ว

      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.

    • @WW5RM
      @WW5RM 3 ปีที่แล้ว +1

      @@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
      @WW5RM 3 ปีที่แล้ว +2

      My furthest QSO is 9100 miles / 14,650 km.
      Jan - ZS6HA in South Africa.
      I am in Texas.
      WW5RM

    • @pauldenisowski
      @pauldenisowski 3 ปีที่แล้ว +2

      ​@@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!

    • @pauldenisowski
      @pauldenisowski 3 ปีที่แล้ว +2

      @@WW5RM Impressive! The long path between EM23 and KG53 would be about 15,800 miles :)

  • @storaman12
    @storaman12 2 ปีที่แล้ว +1

    Excellent

  • @richardweir5497
    @richardweir5497 2 ปีที่แล้ว +1

    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??

    • @Network_ned
      @Network_ned 3 หลายเดือนก่อน

      I was wonder the same because “

  • @2ysur
    @2ysur 4 ปีที่แล้ว +1

    Well done.

  • @abundantharmony
    @abundantharmony ปีที่แล้ว +1

    I wonder if there are any flat Earth radio people out there...

  • @RichCasey
    @RichCasey 4 ปีที่แล้ว +1

    Thanks for a great presentation! Will pass along to other ham operators. N5CSU

    • @Rohde-Schwarz
      @Rohde-Schwarz  4 ปีที่แล้ว

      Hi Rich,
      thanks for the recommendation.

    • @pauldenisowski
      @pauldenisowski 3 ปีที่แล้ว

      Thanks Rich! 73 de Paul, KO4LZ

  • @raghumehra4949
    @raghumehra4949 2 ปีที่แล้ว

    Anda boleh memilih untuk salah satu daripada hadiah di atas

    • @pauldenisowski
      @pauldenisowski 2 ปีที่แล้ว

      Pemberian ilmu adalah anugerah terhebat :)

  • @tonyturtle5805
    @tonyturtle5805 4 ปีที่แล้ว

    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

    • @RichardKCollins
      @RichardKCollins 2 ปีที่แล้ว

      Maybe you should make a video to share this particular vision of how things work. The words are not quite enough.

  • @LawsonIris-u9f
    @LawsonIris-u9f 4 หลายเดือนก่อน

    Hernandez Shirley Smith Cynthia Perez William

  • @rippin187
    @rippin187 2 ปีที่แล้ว +1

    Send this to people who think the earth is flat. Prepare to be amazed by their ignorant defiance.

    • @pauldenisowski
      @pauldenisowski ปีที่แล้ว

      If the world were flat, there would be no long-path propagation :)

  • @agonizedanguish6267
    @agonizedanguish6267 ปีที่แล้ว

    Giggity giggity Recon

  • @Hiujh-f5m
    @Hiujh-f5m 4 หลายเดือนก่อน

    Garcia Brian Anderson Sharon Miller Richard

  • @mariasaatcheson8843
    @mariasaatcheson8843 3 หลายเดือนก่อน

    Miller Joseph Williams Barbara Gonzalez Donald

  • @GildaMills-i9q
    @GildaMills-i9q 3 หลายเดือนก่อน

    Thad Spring

  • @WillieMorrison-o7u
    @WillieMorrison-o7u 3 หลายเดือนก่อน

    Tessie Crossroad

  • @TinishaBurden-d3b
    @TinishaBurden-d3b 3 หลายเดือนก่อน

    Nikolaus Lodge

  • @KennethJones-k1y
    @KennethJones-k1y 3 หลายเดือนก่อน

    Moshe Gardens

  • @AlexanderTolley-j9y
    @AlexanderTolley-j9y 3 หลายเดือนก่อน

    Von Station

  • @ShelleyAlger-o1e
    @ShelleyAlger-o1e 3 หลายเดือนก่อน

    Libbie Summit

  • @NettieRodriguez-r2y
    @NettieRodriguez-r2y 4 หลายเดือนก่อน

    Hall Daniel Lopez Sandra White Margaret

  • @EsmeContreras-x1s
    @EsmeContreras-x1s 6 หลายเดือนก่อน

    Wow, it's really good. It's very attractive and the AD is very interesting

  • @LitzyHutchinson
    @LitzyHutchinson 6 หลายเดือนก่อน

    Wow, it's really good. It's very attractive and the AD is very interesting

  • @LitzyHutchinson
    @LitzyHutchinson 6 หลายเดือนก่อน

    Wow, it's really good. It's very attractive and the AD is very interesting

  • @MiaWilson-i5o
    @MiaWilson-i5o 6 หลายเดือนก่อน

    Wow, it's really good. It's very attractive and the AD is very interesting