ENDFED: Choke vs No Choke. Field Measurements.

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  • เผยแพร่เมื่อ 22 ธ.ค. 2024

ความคิดเห็น • 14

  • @yotubeurk
    @yotubeurk 2 หลายเดือนก่อน +1

    You probably put the rf choke to close to the feed point.

    • @CrazyChekov
      @CrazyChekov  หลายเดือนก่อน

      there was a second choke on the transceiver side.

  • @multilecful
    @multilecful 2 หลายเดือนก่อน +1

    You should have your choke next to the radio. Otherwise you have no groundplane which will be the coax sheath. What you have done is choked it off. You only need one choke.

    • @johnnorth9355
      @johnnorth9355 2 หลายเดือนก่อน

      Correct. The idea of the choke is to stop unwanted current travelling down into the radio from the coax. I use a choke at the radio end with great results in stopping both noise and unwanted effects on the transceiver. Just my two penny worth.

    • @CrazyChekov
      @CrazyChekov  2 หลายเดือนก่อน

      there was a choke on the transceiver side too. also mentioned it in the video somewhere.

  • @vladtepes481
    @vladtepes481 หลายเดือนก่อน

    You misunderstand the purpose of the choke. It is usually impossible to see the effect of a choke using an antenna analyzer. The choke prevents RF coming back on the shield. RF on the shield will cause the Radio to think the SWR is much higher but you need to apply power and the problem increases with the amount of power. You can place the choke near the radio or a quarter wave back from the antenna. Alternatively, a counterpoise can be used. Good news is that your high loss coax will help a bit. There is so much wrong here that it is starting to hurt my head. The others below are also correct.

    • @CrazyChekov
      @CrazyChekov  หลายเดือนก่อน

      There was a second choke on the transceiver side. I'm testing what makes sense in the field.
      The "high loss coax cable" loses about 0.2dB at 7MHz. Just measured it.
      Don't want that your head gets hurt. Please stop watching. :)

    • @vladtepes481
      @vladtepes481 หลายเดือนก่อน

      @@CrazyChekov Your big problem is not the coax but rather your choice of tools to determine the effectiveness of the choke.

    • @CrazyChekov
      @CrazyChekov  หลายเดือนก่อน

      ​@@vladtepes481
      So the coax is now not the problem anymore. :)
      I think you are misunderstanding in general what I try to accomplish here.
      I'm testing which setup is the best for the field. Low power. The priority is to have as few parts as possible (less weight) and the faster the better. I just try nearly all possible combinations. I not claim any theory. I make simple measurements for receiving and transmitting.
      But lets go with your theory.
      The RF coming back on the shield without the choke --> let the SWR meter read a much higher number.
      But in my test I adjusted the SWR the same for both setups I compared.
      That would mean --> my test would favor the setup with the choke. Wouldn't it?
      But...the real world results were nearly identical. No effect on receiving, transmitting.
      --> What does that mean to your theory?
      It may be different with higher power etc. I don't care....in my case it had no effect.
      So I chose the one with less parts....meaning no choke at the feed point.
      Simple try end error of possible combinations.
      Do you have a real world demonstration and measurement ( not in the lab ) what effect your theory has on the receiving and transmitting?
      ...and if not...please then go out, make your test and share it.
      Then maybe we can learn some stuff.
      If you just want to call people stupid (hurting my head...thats in the end a mild version of it) without giving me suggestions what I could try instead....your comment is useless to me so please don't waste my time.

    • @vladtepes481
      @vladtepes481 หลายเดือนก่อน

      @@CrazyChekov An antenna analyzer is the wrong tool. It can't help. You might use an RF current meter to measure currents on the coax. You could also apply power try 50-100 watts. SWR will look higher without a choke (if this is a problem). Be aware current varies with position in the coax just as it does on an antenna. The coax is only a problem if the loss is significant. There is also additional loss due to swr. The SWR at the rig is lower than that at the antenna. You can use your analyzer to measure SWR at the antenna by recalbrating with the feedline in the system.

  • @yotubeurk
    @yotubeurk 2 หลายเดือนก่อน

    Do not place the sheath current filter directly underneath the feed point of an End Fed antenna.

    • @CrazyChekov
      @CrazyChekov  2 หลายเดือนก่อน

      if you have a specific test in mind please let me know.

  • @n0vty873
    @n0vty873 2 หลายเดือนก่อน +1

    running a choke that close to the 49:1 requires a ground radial, some people have no clue.

    • @CrazyChekov
      @CrazyChekov  หลายเดือนก่อน

      that will be also tested of course. feel free to leave "mr. expert".