I remember when phones were small

The EM spectrum and it's applications are fascinating! Science is spooky

As the air gap breaks down a path of plasma is created, which is the lowest resistance path, and that's the path the electrons will follow. The plasma path will move with moving air, to which the plasma itself contributes, because it heats up the air surrounding it. Look up a video on "Jacob's Ladder". The path gets longer as the arc climbs up the ladder, and that's because the hot air rises. So you get the paradox that the arc will not always take the shortest path.

60 Symbols > Reality TV Thank you for sparing me from my roommates terrible taste in TV shows!

Great video. I love antennas! I remember stringing up my own dipole between two tall trees and using the Earth as a ground plane. With some copper wire and some 50 ohm coax you could make a decent antenna.

5/8 th vertical, folded dipoles, capacitance hats, coil loaded whips, Beverage aerials, Yagi-Uda arrays, fractal aerials, ground plane 1/4 wave dipoles, ferrite cored coils and the list goes on. Talk to a radio man. How jolly to find when you've asked the folks round, The joys of your set to be sharing, That the battery's battered, Condenser condensed, And the aerial out for an airing!

Stumbled on this vid in 2017, didn't realize it was that old until I saw the kind of phones they were using lol

@Guru_1092

5 жыл бұрын

Well, at least the information holds up pretty well, right?

So like when I have a magnetic compass and it moves due to magnetic fields, what does that mean in terms or particles/photons? I assume that a traveling electron produces a magnetic field which is detectable. But I assume that when I detect it I am not observing photons? I can observe some one turning on and off a magnetic field, but when is the point where I am observing photons vs. observing a magnetic field? I mean by someone turning on and off electromagnets, they can send me a message that I observe with the compass. But am I observing photons or fields or both? Can I communicate without photons?

The internal AM antenna functions a the same as a that FM whip antenna on that portable radio & all antennas. Th relative motion of a radio wave relative to a conductor creates a current in the conductor. That's what he was explaining with that ball in the clear tube. I wished he would have touched on fractal antennas too, but that may require a series of videos.

@2martino3 Essentially the same way we can take white light (all colors together) and pass it through a filter and get only one color/wavelength out. Though instead of passing it through solid medium, you're futzing with the properties of the antenna/receiver to make it only susceptible to a certain frequency or amplitude.

Why does it have to be 1/4 of the wave length? So the ceramic reduce the wavelength? Will it lose lots of power through this process?

Could you please tell me which Physics building you entered into?

Impedance matching. A quarter-wave antenna presents an impedance of 50ohms at its base. It is possible to create variations that exhibit 'gain' by the concentration of energy in 'lobes' that radiate out from the antenna. These variants use different fractions of a wavelength such as 5/8 or 7/8 and present a different impedance to the equipment attached to it. The inductance of a coil in the antenna alters the impedance to become 50ohms which is important to a transmitter output stage.

what about fractal antennas and the coil that is in an am radio

It would be interesting to hear from professors at Nottingham about cellphones and cancer: it's on the news from time to time but it seems there is no ultimate word on that.

Oh, the problems I had ... when I first moved from London to NY in the early '80s ... and tried to get a new stereo/radio set up! I kept asking about an "aerial", to be met with ALL blank looks. When the installer referred to "antennas", it was ME with the blank look -- only insects/arthropodae that had "antennas"! These days, when both sides of the Atlantic are "fully" linguistically integrated, such problems rarely occur!!!

Was there ever any doubt that getting your choice in science videos beats "reality" TV? =)

@notapetit yes I remember seeing something about how they changed mobile antennae as we know them. more length in a smaller package.

Light is electromagnetic radiation that is measured in wavelength, so yes alternating current occurs in nature Another example is that radio astronomy is based on detecting electromagnetic waves with wavelengths much longer than light

At a guess it would be because the only electronics requiring power to receive AM signals is the amp however to receive FM signals you require more electronics to decode the signal and the amp.

I have noticed that all radios get worse and worse reception as time passes (I'm talking years.) More and more noise. Why does it happen?

This channel has been going for a while.

I'm not sure about physics, but depending on the frequency of usage (lower frequency communications can be SSB), some circuits draw more current at higher frequencies, where FM is usually used. I could be wrong though.

You might be grounding out any static electricity that may accumulate on the antenna thereby reducing noise. In fact amature radio antennas are often "DC grounded" that means that they are conected to ground potential trough an inductor that lets trough static electricity but blocks the signal so it can still go to the receiver instead of going straight to ground. Nevertheless your body acting as part of the antenna might also play a role.

No, not the ones that have been described as "Several much‐discussed issues limit the evidence base (typically including small numbers, heterogeneity of outcome, retrospective self‐reporting of exposure and the need for long follow‐up periods to evaluate longer‐term health risks)", you're quoting Bad Science research paper. sciencebasedmedicine is a website, they have few articles published on the subject, I won't be quoting stuff that is available there with references

i'm going to take a guess and say that your body is probably slightly extending the aerial. Making it easier for the aerial to pick up the wavelength.

what about fractal antennas?

Basically but they do still age. There is a nice article on IEEE Spectrum about transistor aging if you are interested.

@colinstu your body is a conductor. If you grounded yourself and touched the antenna the signal on the radio would be much less

I remember not having internet, but we always had a phone. At least, until we started using the internet. 🤣

fractal antennas much?

Can't believe we used to use THAT cellphone a decade ago

A question for you physicists,when I listen to longwave my batteries last longer than if I listen to FM. How come?

Hey my antenna is tuned to 9.455 MHz I must listen to the shortwave radio during the late night and early morning it is a part of my culture

Physical results of learning by doing experience accumulate and become professional, "for all practical purposes", very effective. So an Antenna is mostly a jargon for a device where fractal conic-cyclonic coherence-cohesion module-ation is the dominant functional phenomenon. An emitter-receiver condensation of relative-timing @.dt zero-infinity instantaneous logarithmic Superspin Superposition-point-> transverse trancendental holographic projection-drawing in relation to "it's always NOW" Singularity Reciproction-recirculation. "The Universal Spark of Existence".

Transistors do age slowly, but more likely it is the capacitors. Electrolytic ones particularly. You must be careful when powering up any decades old electronics for this reason. Normally they just drift out of spec, but sometimes it is so bad that they vent and burn. Dust buildup and corrosion on parts can also affect operation.

A person's arm span is usually about the same as their height; if he's 2m tall, his arm span is about 2m. Close enough.

Umm, the electric field lines from an e- would be inwards (-ve charge) whereas from a proton would be outwards (+ve charge). This is with reference to 3:58 Just saying

Wow a genuine antique mobile phone.

Funny how even scientific minds have difficulty making something relatable. In this case, however much of an expert he is on radio wavelengths, the only equivalent he can think of for 1500m is to do with the length of the running race, so he says "three times round the track". But in fact, it's 1.5km, just a little short of a mile (1 mile=1,609m). I think a straight line distance is easier to think of than how many times round a race track.

@PlasmaHH

7 жыл бұрын

So you say "1500m is 1.5km" is easier for people to understand a distance than trying to come up with something they might know in size and say "three times that"? Thats like saying "we have 100 billion stars, to better understand and picture that think about it being 100 thousand million stars"

Well, I haven't got this years memo yet, so the overlords may have changed. But I'm sure that the lizard aliens were in control last year...

point is low level RF is safe and even most high power output is fine. now have fun and play with RF, get a license. The FCC has numerous datasheets about exposure and conditions.

it would be possible if not for one minor detail: how long have the cell phones were on the market (well over 30 years now, even leukaemia has shorter gestation period, let alone ear-cancer) and how the average radiation emitted change (it steadily decreases with each generation)

Nice video. :-)

Great illustration of this concept! We take antennas for granted every day, to actually see how the objects interact with electromagnetic waves is incredible.

The 1.4 GHz isn't referring to a processor speed - it's referring to the frequency of a photon.

Haha classic youtube. Bringing us all together after 10 yrs

I dont understand how there can be so many different signals flying through the air and affecting all antennae, yet we can choose to listen to only one, without interference..

My dad used to work on those a few years ago.

Nice intro on antennae. Thanks!

@hjembrentkent6181

7 жыл бұрын

Nice plural latin. Thanks!

@aquataerra7325

7 жыл бұрын

biologist. It's a curse. :D

Interspersed with breaks from RKO Radio pictures.

Gale Boetticher ?

Those punk professors in nottingham as so interesting, and great speakers even on camera. makes me want to go to nottingham

like Occup Environ Med 2007;64:626-632 doi:10.1136/oem.2006.029751 ?

This man must be huge if his arm spans is 2-3 meteres.

Of course he was giving a relative example. Personally I'd outstretch my arms & would have finger tips to finger tips would be nearly 2 meters In my case it would be 1.9 meters

A mobile phone? That will never catch.

Google: "science based medicine cell phones", you'll get nice graphs, links to medical papers and indepth explanations.

I was always taught that an Aerial was Recieve Only whereas an Antenna was Send and Recieve ?

Ah, just wait. A tidal wave of ear-hole cancer awaits the next generation.

I thought transistors were nearly indestructible because they have no moving parts?

Dear me. It was a joke.

if i could see radio waves instead of visible light than WILL I SEE THE OSCILLATIONS OF THE WAVE BECAUSE OF LARGE WAVELENGTH ?

@kickmonlee3390

8 жыл бұрын

Yes, your eyes pick up certain frequencies as do antennae. What's happening in the radio is its tuning to a certain frequency and the magnitude/intensity and oscillations of the waves received are the data that is the music played. If you could see in radio waves and we're trying to listen to a certain Radio Station it would be equivalent to seeing a certain color oscillate in brightness.

@chrismofer

8 жыл бұрын

+Abhishek Dubey yes. if you had photoreceptors that could see past the visible spectrum to radio, you would see different frequencies as different colors. furthermore, as glass is transparent to visible light, most materials are transparent or at least semi-transparent to radio waves.

@IamGrimalkin

8 жыл бұрын

No, even long-wave is in the kilohertz and up (thousands of waves per second). The distance only sounds big because light travels really fast. Also, you wouldn't be able to create an image with radio waves with an eye your size because of the diffraction limit.

I think some people might go ahead and take some of the analogies for truth.

3:00 Uuuhh.... This reminds me of the Silent Hill radio

@OhYeahMilkIt He could be 7' tall, you don't know. :P

TIL _arials_ are antennas

yes, shit works great for picking up signals

Ultra temporal Entanglement..

yes

You should had asked him why he insists on using "aerial" instead of "antenna"... I'm just curious.

@RogerBarraud

8 жыл бұрын

+dromeiro Go forth and Stultify :-/ #Derp

@thekaxmax

6 жыл бұрын

dromeiro he's English

@DeathBringer769

6 жыл бұрын

Same reason he'd say "lift" instead of how we would more commonly choose the word "elevator." He's English. There's regional dialect differences from American English. That's sort of how regional differences work with language, lol. Depending on region the language changes and is used somewhat differently from other areas, often times. The bigger the distance, the bigger the effect tends to be. When you're crossing over an ocean and into a different country from which English itself originated, then even more so. This is also why you see separate listings for "British English" or "American English" in dictionaries pretty often if something is specific to or is more prevalent in one region or another.

4% of 29,000 feet is 1160 feet, so if Mt. Everest were suddenly found to be 4% shorter, I think it would indeed be important! We would have to reevaluate our measuring systems and geology, for a start... XD

Hahaha, true :D That looks kinda akward. It could be he's imagining the length of the top of the wave between his hands where his hands would be only two zero crossings, which is half the full wavelength of 2 to 3 meters? I dunno, I'm just throwing him a bone here. Hehehe.

2 isnt outlandish but 3 is taking the piss lol

This is likely due to transistor aging.

Nearly everybody is using cell phones, there is no increase in cancer rate from 30-40 years ago. If you don't have an effect and your performing the test over and over you are bound to have few positive tests, depending on your p-value, every 20 to 100.

4:00 This is not an electron. It is a pink ball.

Interesting. You're directly quoting an article - well, a brief abstract of several topics, from the very peer reviewed journal you're dismissing? You don't even realize, that the issues, that you think are a rebuttal of "Bad Science", are those, the authors themself state for good reasons to do more reaserch on long term exposure!

Learned something about how to reduce the aerial length. Thank you!

I remember the rise of the Yupie.

a person who is 2 meters tall has an arm span, from fingertip to fingertip, of 2 meters.

I had a mobile Phone with antenna once. Unfortunately the battery broke down. I would love to still use it today and see the expression on people's faces when I would extend the antenna on that huge thing, haha.

@fryncyaryorvjink2140

9 жыл бұрын

you should modify the old phone to be a case for your new phone

i was so just going to write that O.o

I always thought the antenna should be half the wavelength not a quarter

@tehPwnzor7306

9 жыл бұрын

John Fletcher A dipole is 1/2 wavelength, but the feedline is attached in the middle, making each 'side' 1/4wl.

@redknight344

4 жыл бұрын

its because that's not a dipole but a monopole, so it can be a quarter wavelenght but acts like a dipole.

"there is no increase in cancer rate from 30-40 years ago." Who sais? What kind cancer is he referring to? And what population was (s)he referring to? Seriously, generalized like this, it's not even wrong.

Hydrogen Spin flip events. Rare.... MRI...

Hate to say it, but this was the least informative Sixty Symbols video I've seen. I have a better grasp of quantum mechanics, particle physics, and general relativity from the other videos than I do about antennae from this video, even though we all directly use antennae every single day of our lives. Missed opportunity.

Nice try, but when you start talking about charges producing magnetic fields, my brain hears "Basically this part is magic, and it's made of magic, and we have a stick on the other end to dowse for that magic."

@RogerBarraud

8 жыл бұрын

+Thomas Patnode Go find the video of Feynman being asked to 'explain' magnetism and electricity... and why it *is* 'magic' :-)

@thekaxmax

6 жыл бұрын

Roger Barraud Yup, cos that's what he says--and that we understand it rather well.

Sixty

I suppose this professor works with metrics only in theory because he has no idea how long 2-3 meters are :)

@NomadUniverse

6 жыл бұрын

He was pretty close to 2m. Your fathom should be longer than you are tall. Within 90% is a lot closer than "no idea".

@timewalker6654

5 жыл бұрын

wtf are you talking about, he was pretty close

2023

Dust

:-D OVERCLOCK! Use liquid nitrogen :-p

first of all: radio waves have nothing to do with ionizing radiation, nobody whith a shred of knowledge would claim that, otoh. there are a number of organisations stating, that more research is needed to assess a possible cancer risk: IARC/WHO, CDC, NCI, NIEHS. Definitely not as crackpot or anti-science as you claim.

this vid was not one of the better ones. sorry :S

Antennae may be interesting but this is just a man walking around pointing at them.

@MorbusCQ

7 жыл бұрын

Remember the part where he explains the physics behind the technology?

@LoneWolfZ

6 жыл бұрын

I have studied antenna theory quite a bit for an ordinary person and I'm sorry to say, this is about as deep as you can go without jumping in head first.

@queenfggggu

6 жыл бұрын

Turn the sound on

1.4GHz? overclock that shizzle :)

dude says "eh" and "ehm" too much

yes