89. DIY AM Antenna "Amplifier"

แชร์
ฝัง
  • เผยแพร่เมื่อ 26 ส.ค. 2024
  • A simple passive AM antenna "amplifier" to pull in those weak stations. Inexpensive and has more sensitivity than many of the commercial models.

ความคิดเห็น • 46

  • @wojciechbartczak3109
    @wojciechbartczak3109 4 ปีที่แล้ว +10

    Your videos are extremely useful. Electronics is partially my education and partially my hobby. Since recently I have no space and/or time, I left only with watching videos. I've watched tons of videos on YT and the whole internet and there aren't a lot of them pack with content like yours. Please don't give up!

    • @TheOffsetVolt
      @TheOffsetVolt  4 ปีที่แล้ว +4

      Thank you, I'll try to get some more videos out.

  • @heinerrambold8889
    @heinerrambold8889 6 หลายเดือนก่อน

    Loops for the low frequencies are not hard to build. However, with increasing frequency it becomes more and more challenging. Thanks for the video!

  • @aerofart
    @aerofart ปีที่แล้ว

    You’re a good man, TOV. Thanks for all you do for the community. Your videos are tremendously educational and entertaining.

  • @Debraj1978
    @Debraj1978 3 ปีที่แล้ว

    Lot to learn from your video. I am an electrical engineer, but work on power side. But learning basics is something I love to do all time and your videos are superb.

    • @TheOffsetVolt
      @TheOffsetVolt  3 ปีที่แล้ว

      I appreciate that. The power side of electronics - the dark side...lol.

  • @satheehkumars2201
    @satheehkumars2201 10 หลายเดือนก่อน

    your video is very much usefull to me because I was in problem to get Am sation in my radio. straight away I am going to make one for my use. I will came back to you after I construct the same and use.
    Thank you very much for your kind information

  • @deltagold9646
    @deltagold9646 4 ปีที่แล้ว +1

    Content is excellent, thank you.
    After the FM portion of the Elenco is complete, It will be a pleasure to grant your site a donation.
    Your high level of proficiency is well worth it.

    • @TheOffsetVolt
      @TheOffsetVolt  4 ปีที่แล้ว

      I appreciate your feedback. I don't know that I could take any contributions from viewers. I feel like I would have to publish more content to make it worth a contributors money. Thanks for watching.

  • @Dad-ij2qy
    @Dad-ij2qy 3 หลายเดือนก่อน

    As an EE and former extra-rated ham, I thank you for presenting the best presentation yet on a AM LC resonant loop antenna. I appreciate the RC equations as a functions of frequency. So long as you use insulated magnet wire to make the coil, it' shouldn't matter if the coils are right next to each other, so long as the wires don't get hot enough to melt
    the insulation and short out.
    I heard other AM broadcast band antenna builders proclaim a 1 foot by 1 foot square
    for making the loop. Are you sure 2 foot by 2 foot is the right value? I suppose will have to do further research on coil building to determine the inductance of hand-wrapped square
    loops..
    I am hoping to find a source for the variable air capacitor for tuning this magnetic loop antenna. If you know where I can buy one, please post here.
    I hope to find one, so I don't have to run wire outside my house ( I live in an area where air temperatures drop below freezing for 2 to 3 months of the year), so I don't have to drill a
    hole in my house to string a grounded antenna outdoors with 50 to 100 feet of wire.

  • @bapibapi7371
    @bapibapi7371 ปีที่แล้ว

    Many many thanks to you for your tutorial videos. I am from india

  • @suhailasaba1051
    @suhailasaba1051 3 ปีที่แล้ว +1

    4:48
    Great video.
    Thanks for the formula.

  • @cerglabs3646
    @cerglabs3646 4 ปีที่แล้ว

    Great channel! I especially loved the Op Amp series. I learned a ton!

  • @patricklanra3507
    @patricklanra3507 3 ปีที่แล้ว

    Merci - vos vidéos sont tres interessantes à suivre.

  • @josstark8124
    @josstark8124 21 วันที่ผ่านมา

    How would you hook up an Antenna Analyzer to a closed loop if you wanted to determine resonant frequencies? Would be a big help.

  • @morpher44
    @morpher44 2 ปีที่แล้ว

    for wheeler formula of inductance, you actually want the width of the coil to be greater than .8 x mean-radius, and so a width maybe 10 in or so... with each wire 6 wire distances from each other.

  • @tomdoyle9785
    @tomdoyle9785 2 ปีที่แล้ว

    Excellent content. Great Presentation. Thanks!

  • @mmallick3224
    @mmallick3224 ปีที่แล้ว

    Thank you Sir. Your video helped me a lot. Looking forward for some similar informative videos. I'll try my best to build a similar one. I want to build a smaller one, what will be measurements of the side and the number turns of the wire?(I was successful in building a dipole FM Antenna that perfectly catches Stereo signals from 70 miles aways alongwith other physical obstacles).

  • @scottmorgan5370
    @scottmorgan5370 ปีที่แล้ว

    Could you please comment on what if any the earth's magnetic field would have on something like you have here.

  • @williamhazelwood8288
    @williamhazelwood8288 4 ปีที่แล้ว

    Good video thanks intresting about using the loop antenna to find the source.

    • @TheOffsetVolt
      @TheOffsetVolt  4 ปีที่แล้ว

      They are pretty neat and so simple on top of that. Thanks for watching.

  • @steve-si3oz
    @steve-si3oz 3 ปีที่แล้ว

    Thank you!!

  • @arjunprajapati8352
    @arjunprajapati8352 4 ปีที่แล้ว

    Thank U Very Much Sir.

  • @tomdoyle9785
    @tomdoyle9785 2 ปีที่แล้ว

    Could this, when adjusted for frequency, be used to increase cell phone signals to rural areas? Thank you

  • @railgap
    @railgap ปีที่แล้ว +1

    preselector or tuned antenna but "amplifier"?!? Why would you use that word when you know it's wrong?

  • @michaellagana936
    @michaellagana936 ปีที่แล้ว

    Question can you use that same antenna to transmit a signal?

  • @davidluther3408
    @davidluther3408 4 ปีที่แล้ว +1

    I AGREE WITH YOU ON THE COMMERCIALS THEY INTERRUPT MY THINKING WHEN I AM TRYING TO LISSEN TO THE VIDEOS.WHERE DID YOU GET THAT STAND FOR YOUR PS AND,O SCOPE?I AM LOOKING FOR SOMETHING LIKE THAT.

    • @TheOffsetVolt
      @TheOffsetVolt  4 ปีที่แล้ว +1

      I made it from some spare items around my shop. Best way I know to get something that does just the job you want.

    • @davidluther3408
      @davidluther3408 4 ปีที่แล้ว +1

      @@TheOffsetVolt THANKS!

  • @cameronstolhand7149
    @cameronstolhand7149 3 ปีที่แล้ว

    Would wire as thin as 43 AWG work just as well as a thicker gauge wire?

    • @TheOffsetVolt
      @TheOffsetVolt  3 ปีที่แล้ว

      It can. The wire acts as the inductor so you will have to space those thin wires much closer together.

  • @kisuke6517
    @kisuke6517 2 ปีที่แล้ว

    does this work without the variable capacitor

    • @mmallick3224
      @mmallick3224 ปีที่แล้ว

      No, it won't work. If you aren't available with a variable capacitor, you can create your own sliding capacitor using two tubes, the latter smaller than the previous one in diameter. Wrap the larger one and smaller with aluminium foil seperately and slide larger tube over the smaller one or vice versa. Add two seperate wire over the foiled area of the tubes. As per the diameter, you'll get capacitance from 1~90 pf, which is sufficient for the MW and SW bandwidth.

  • @suhailasaba1051
    @suhailasaba1051 3 ปีที่แล้ว

    Thanks for the video.
    Why should the length of wire be 88 ft ?

    • @TheOffsetVolt
      @TheOffsetVolt  3 ปีที่แล้ว +1

      The wire's length around the frame provided the correct inductance value. This makes it possible to get any resonant frequency in the AM band through the use of the variable capacitor.

    • @suhailasaba1051
      @suhailasaba1051 3 ปีที่แล้ว

      Is it related to the value of the wave length ?

  • @rochtourigny8140
    @rochtourigny8140 4 ปีที่แล้ว

    Could this work with digital TV antenna?

    • @TheOffsetVolt
      @TheOffsetVolt  4 ปีที่แล้ว

      Hello and thanks for watching. No, this wouldn't really work for that signal type. You could build something but ....? I've played around with some digital antennas and found Channel Master CM4228HD to be good.

    • @rochtourigny8140
      @rochtourigny8140 4 ปีที่แล้ว

      @@TheOffsetVolt Thank you!

  • @whatislove2735
    @whatislove2735 3 ปีที่แล้ว

    Please let us know the rules for making this antenna by writing in the comments

    • @TheOffsetVolt
      @TheOffsetVolt  3 ปีที่แล้ว

      First select the frequency range you hope to cover. Let' say you want FM from 88MHz to 108MHz. You have a variable capacitor with a 10pF to 20pf (I just made one up). Plug the highest capacitance and lowest frequency in the band into the equation L=1/{(2piF)^2*C}. Using 20pF and 88MHz you get 163.54nH. This gives you the inductance you need. Build the inductor on a suitable frame. Roll wire onto it and measure the inductance as you do. Stop when you get around 163nH. To find the upper frequency, plug the lower value of your variable capacitor into Fr=1/(2pi* (sqrt of LC)). In this case the answer would be 124.45MHz. Hope that helps.