Oh well, 4th year high school student from Italy here, it's about something we are studying now in physics, the dielectric constant ε. The higher is the εr (relative ε) of a material, the higher is the parasitic capacitance that conductors placed close to that material have. You can think about it as μ for inductors core... The higher it is, the higher is the inductance you can get with the same amount of turns. So, εr of water is 80, while εr of the ground ranges from 4 to 8. Therefore, the more water you have under the antenna, the more is the electric field going trough it and getting influenced by it's high εr. To summarize, the deeper is the water under the antenna, the higher is the equivalent capacity you are putting in parallel with the antenna, this lowering its resonance frequency :)
@Francois_Dupont
Жыл бұрын
what?! you are studying physics and dielectric constant in high school?
@fabriziobrutti1205
Жыл бұрын
@@Francois_Dupont yeah, but it depends from the type oh high school... The literal translation of the type I go in, is "Scientific high school, applied science course". People who go in Classical or Linguistic high school begin physics only at the 3rd or 4th year and do some very basic things such as F=ma
@Francois_Dupont
Жыл бұрын
@@fabriziobrutti1205 okok, where i live it is only the most basics education even at the end of high school. the only reason people fail grades is because the French exam are extremely hard. basically if you have more than 3 errors in a 500words text (in french) you fail high school.
@fabriziobrutti1205
Жыл бұрын
@@Francois_Dupont oh I see... Here in Italy, luckily it's not too easy to fail the finals 😅
@JackFalltrades
Жыл бұрын
Good to see you again, Raisa😊
@JackFalltrades
Жыл бұрын
Since you went through all that work to drill the hole, I hope you went ice fishing after the experiment!
@YLRaisa
Жыл бұрын
At least I still knew the depth of the lake in that place.😂
@kirk1618
Жыл бұрын
I just love your videos and your enthusiasm!! I do have to tell you, I did get cold watching!! LOL. I moved away from the cold a longtime ago. Looking forward to your summer experiments..... actually, just can't wait until the next video!!! 73. -de KN1B
@YLRaisa
Жыл бұрын
Thanks Kirk. I have many summer videos on my channel 😉
@cllaurit
Жыл бұрын
Your videos are always entertaining and informative, you are a great ham and an asset to the hobby. I have instructed a few newcomers to the hobby to look at your channel! Keep up the great work my friend!
@YLRaisa
Жыл бұрын
TNX, Chris, to get newcomers to our hobby is one of the my main goals, 73! Raisa
@F4EPU
Жыл бұрын
Good tests and results!
@YLRaisa
Жыл бұрын
Hi David What do you think about the result?
@F4EPU
Жыл бұрын
@@YLRaisa I will be surprise to test it!
@chrisg7veo495
Жыл бұрын
I think it depends on how many fish in the lake affects the result 😂
@YLRaisa
Жыл бұрын
Excellent idea! 😄Thanks!
@noterbel75
Жыл бұрын
Nice video
@Texas1FlyBoy
Жыл бұрын
I'm glad I didn't fall in the hole when I was snow skiing on that lake! 😂
@YLRaisa
Жыл бұрын
Michael, the hole was not very big. But if you trained too hard, you might have a chance. 😂😂😂
@Texas1FlyBoy
Жыл бұрын
@@YLRaisa 👍Only one leg would fit. 😂
@littleking8448
Жыл бұрын
You do everytime such a lot of work...👍👍👍 The funny thing is, that now in these times, most areas even don't have Fronten lakes anymore. I can't remember, when I was standing in natural ice. What I like about you and your videos, your are such enthusiastic about the Passion Ham-Radio...👍👍👍
@AlteSchutze
Жыл бұрын
Чем больше воды под антенной,тем больше ёмкость этой воды,соответственно частота антенны становится ниже...(я так думаю))
@fabriziobrutti1205
Жыл бұрын
Right... I just wrote a longer comment about it :)
@AlteSchutze
Жыл бұрын
@@fabriziobrutti1205 indeed,your scientific comment more clever than my amateur feelings.😜
@YLRaisa
Жыл бұрын
а я думала, что с увеличением расстояния до земли (до дна озера) частота резонанса наоборот должна пойти вверх...
@danielgiraud2192
Жыл бұрын
73&88 de ZS5DG!
@christher69
8 ай бұрын
How abt making somesort of yagi on the ground/sand ... with preprepped wire elements //Chrus 73
@Philip-KA4KOE
Жыл бұрын
I guess the antenna worked like NVIS?
@g0fvt
Жыл бұрын
The dielectric constant for the ice is much lower than you might expect, similar to rubber or plexiglass, even pure water has a dielectric constant much higher. (it varies with temperature). I think your experimental results make sense. Thicker ice will probably raise the resonant frequency.
@JackFalltrades
Жыл бұрын
So, her result was related to the thickness of the ice rather than the depth of the water. I thought she was looking at the depth of the water as the variable.
@YLRaisa
Жыл бұрын
Yes, I was looking at the depth of the water !! The thickness of the Ice on both positions was quite the same, 40 cm!
@JackFalltrades
Жыл бұрын
@@YLRaisa So, his assumption may be incorrect. 😊
@g0fvt
Жыл бұрын
@@YLRaisa I see, I am sure the same sort of effect applies.
@k9eihamradio
Жыл бұрын
I think that the reactance between the antenna elements and the Earth plus the water is making the antenna seem longer. That would tend to suggest the effect is inductive like base-loaded antennas. Was it -j or +j on your rig expert?
@johnforte3466
Жыл бұрын
Raisa, you are mixing sonar with hf. 73 & 88
@paulwright7551
Жыл бұрын
You're adorable, as an American I love your accent, next time say "Moose and Squirrel" (Rocky and Bullwinkle cartoon reference) ! What you are experiencing is what they military has known for 80 plus years. Lower frequencies can be transmitted under water as well. Look at WWII submarine antennas.
@YLRaisa
Жыл бұрын
TNX for your comment. But I used 20 m band, not very low QRG! submarine antennas are for really low frequencies !
@ronwolenski-n8wcr
Жыл бұрын
Interesting video! Now get out of the cold and warm up :)
@YLRaisa
Жыл бұрын
😆🥶
@hamsidoroff7056
Жыл бұрын
Раиса, здравствуйте! Как там ваш усилитель от Р-140? Задышал?
@YLRaisa
Жыл бұрын
Добрый день, Папа Женя его починил, работает.
@HerbHorn-f3r
Жыл бұрын
Well I can’t believe the weather difference from Ohio if that’s a recent video! Would the results be the same as just laying it on the ground? I may try it to check! Great discussion love the different things you try very entertaining! KE8RJD
@YLRaisa
Жыл бұрын
Thanks Herb, It was shooting in February :)
@ManuOutdoor
Жыл бұрын
Nice Video Raisa! I don't know what are the Ohms of Ice but somehow your Analyzer get 50 OHM of 13 MHZ ;-)
@IrishHamRadio
Жыл бұрын
Hi Raisa, Mad idea! 😅 Can I ask was the minimum swr value different between the first and second positions?
@thenomadicham5329
Жыл бұрын
I am wondering about temperature difference between the two tests and the difference with depth. How much time elapsed since the first test. You might research this too. Submariners know about inversion layers in large bodies of water with depth. Our two countries have figured this out in order to operate RF while submerged. You might also consider doing your test with the lowest possible frequency your allowed to use in whatever country you are in. It might also lead to a repeat of this experiment in a body of water where you can sink the dipole to measured depth. You started off with a fun idea that can lead to more fun ideas as I have mentioned. Now. Do you have ballooning groups you could test using a long wire dangling from a gondola? Imagine operating 160 meters from a balloon. Just what bands are you allowed to operate on?
@thenomadicham5329
Жыл бұрын
I meant to suggest doing this again in the summer time.
@okhamradio
Жыл бұрын
Очень интересный тест получился, только не понятно почему параметры зависят от глубины.
@YLRaisa
Жыл бұрын
Вот и мне не вполне понятно, но изучу комментарии, надеюсь, пойму.
@gabrielsansar6187
Жыл бұрын
you need to call it the RAICA antenna
@YLRaisa
Жыл бұрын
😅
@YuriiKostychov
Жыл бұрын
Hello there! I suppose that an electromagnetic wave propagation constant along the wire deal great impact in impedance o dipole. Value of propagation constant defines electrical length of antenna, and surely resonance frequency position. Radiator located at the border "air // ice+water", all of those material has different dielectric permittivity (eps): air has eps=1, ice eps~10 (it tightly depends on temperature), water eps ~80. So propagation constant is defined by effective value of eps (eps_eff) [more specifically (eps_eff)^0.5], which in turn is defined by value (dimentiones) of material and skin depth (and more parameters) around the dipole. Best regards Yurii. Доброго здоровья, я думаю, что положение резонанса диполя определено электрической длиной лучей антенны, которая в свою очередь зависит от постоянной распространения вдоль провода излучателя (волнового числа/коэффициента укорочения волны) - а оно уже определено эффективным значением комплексной диэлектрической проницаемости (eps) материалов, окружающих излучатель. Антенна размещена в "пироге" из воздуха, льда и воды с отличными значениями eps (я тут говорю о действительной части) воздух=1, лёд~10 (сильно меняется с температурой), вода~80. Когда Вы меняли место расположения диполя, изменялись и компоненты, его окружающие, их пропорции - менялось значение eps_eff - изменялось и значение резонансной частоты. С уважением Юра. N.B. эффективнее (возможно) использовать другой номинал балуна (согласующего устройства) - в смысле выходного сопротивления (из опыта рекомендую от 600 до 800 Ом). Тогда получится широкополосная антенна, не требующая тюнера, но длина плеча должна быть не менее половины длины волны (на нижней рабочей частоте) - для 13 МГц длина плеча должна быть ~12 метров .
@YuriiKostychov
Жыл бұрын
Я увидел комментарии ранее - да присоединяюсь к ним - оставляю стоящим внимания свой комментарий в части возможности широкополосного использования .
@YLRaisa
Жыл бұрын
Юрий, спасибо за такое глубокое осмысление моего эксперимента :-)
@R1CBU
Жыл бұрын
Мне показалось или при измерении второй позиции рядом осталась лопата хотя в первом случае ее не было? 😁
@YLRaisa
Жыл бұрын
Ты думаешь в ней дело? :)
@R1CBU
Жыл бұрын
@@YLRaisa запросто! У меня после установки в 3м от КВ антенны УКВ резонанс довольно существенно уехал.
@elberttanner6189
Жыл бұрын
To make it simple, think of your experiment as playing a flute. As you blow into the flute, if you lengthen the resonant column, the frequency goes lower all other factors being the same.
@YLRaisa
Жыл бұрын
TNX, This is a fantastic explanation ;-)
@elberttanner6189
Жыл бұрын
@@YLRaisa Your experiment does pose for me this question, "Is the Antenna incorporating the Ice as part of the radiator, or is it, reacting only to the distance above the bottom of the Pond?" This is why I suggested additional experiments, starting with you fine work so far, but adding a non-conducting mast of up to say 10 to 12 meters placed on the Ice and then work up at 1 meter increments from your original position of the Antenna on the Ice. 72 de KB5SXC/qrp.
@luckydubeinrc5165
Жыл бұрын
Raisa..what happens when you raise any antenna in the sky , frequency changes as we go higher, same when on the ground, or over water.. we have capacitance changes and inductance acting on the wire (or yagi).
@digitalmediafan
Жыл бұрын
Another amusing video Raisa you are definitely one of a kind...what did you say at 1:27 ?! I like the ttttruuu sound at 0:41 😊 You are the definition of happiness !
@YLRaisa
Жыл бұрын
Daveб I sad "It goes down at me" 😅
@thenomadicham5329
Жыл бұрын
Yes, we could use more like her.
@digitalmediafan
Жыл бұрын
@@YLRaisa ah hmm oooh 🙃
@digitalmediafan
Жыл бұрын
@@thenomadicham5329 bubbly is the word. I wish she would say the word effervescent. I know I would find it funny with her accent 😂
By the way. Your video here, shows us that experimenting, testing, failing, and persisting, are done by brave people who in history moved science forward God bless
@ALEXSANDER109B
Жыл бұрын
😂😊❤73/51 PP5ACP TOP TEST
@andrewscharbarth2099
Жыл бұрын
The deeper water and lake bottom probably has different capacitance and conductivity which would absolutely change the swr.
@YLRaisa
Жыл бұрын
Andrew, tnx for your conclusion!
@MI7DJT
Жыл бұрын
This was so much fun to watch Raisa! Sorry I can't help with an explanation.
@YLRaisa
Жыл бұрын
There are already some good guesses and explanations here. Thanks 😀
@DK5ONV
Жыл бұрын
💯👌🙏🙋♂
@andzelamike5159
Жыл бұрын
Good👍
@marcelotoniolo4434
Жыл бұрын
Lot's of fun on ice uh ? Not sure exactly what you were trying to achieve there. Waiting for a video with you using the radio connected to this antenna "on ice".
@gabrielmanuelmarquesiesque1156
Жыл бұрын
I cannot help but it is a very interesting test, Thanks for the video !!
@delmarbish3926
Жыл бұрын
Maybe we should be fishing 🎣 ❤😂
@AlteSchutze
Жыл бұрын
Удочку бы взяла,рыбки на ужин наловила.Такое озеро наверняка кишит окунями.)
@YLRaisa
Жыл бұрын
Подледная рыбалка дело особенное, нужно уметь. Но я, к сожалению, не умею :)
@AlteSchutze
Жыл бұрын
@@YLRaisa в любой женщине природой заложено умение охотится и ловить рыбу..проверено на практике..Просто нужно один раз попробовать,а дальше радиолюбительское хобби может отойти на второй план 😜
@AlteSchutze
Жыл бұрын
@@YLRaisa тамошние озёра-это что-то..я не был в Финляндии,но давно, в начале 80-х,когда был в ленинградской командировке,питерские друзья повезли меня на рыбалку в Карелию.Эта рыбалка(правда летняя)мне до сих пор снится.С тех пор больше нигде не видел такой изумительной красоты природы и такого обилия рыбы.Если бы ещё не комары...))
@Dromidont
Жыл бұрын
👍👍👍👍👍
@paulsengupta971
Жыл бұрын
What a wonderfully bonkers experiment! Ham radio encourages experimentation...
@YLRaisa
Жыл бұрын
yes, Paul, I have a Passion for Experimentation ;-)
@fabiomassimomarinelli3492
Жыл бұрын
Hi Raisa. The lake depth increase the equivalent lenght of the dipole. From the electromagnetic point of view the depht adds length. So the resonant frequency become lower. Bye ! 73 from Fabio IW0HPU
@YLRaisa
Жыл бұрын
Hi Fabio, thanks for your explanations! Raisa
@fabiomassimomarinelli3492
Жыл бұрын
@@YLRaisa thanks to you Raisa and thanks to your experiments ! It's the right approach to the ham activity ! In fact the contact of the dipole with the ground, and in your case with the ice of the frozen lake, increases the electromagnetic lenghth due to the extremity effect with a capacitive effect. Thank you Raisa for your nice and kind videos promoting communication and brotherhood among all men and women. Bye. 79 and ciao. Fabio
@DXCommanderHQ
Жыл бұрын
I think this is a combination of dielecric constant AND height above the bottom of the lake. Maybe!
@YLRaisa
Жыл бұрын
Ways of radio waves are inscrutable ;-) My DXCommander is located 50 m from that place where I was filmed on Ice ;-)
@ATOMSHAMRADIO
Жыл бұрын
Ohh god here we go
@ДенисГареев-у3и
Жыл бұрын
С победой !!!
@Petertronic
Жыл бұрын
Very good science, I enjoyed this experiment. Always learning! Wow that ice is thick. G7LPG
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