Thekrishankumar - Krishan Kumar

AM & FM: How Radio Works 

Lately I’ve been thinking about how the things I use every day actually work, and since I listen to a lot of podcasts, you can guess where this post is going: radio. 

In a studio, a microphone converts sound waves from a person’s voice into an electronic audio signal. If this was sent out by itself, it would only travel a few metres in air before it faded out. To get radio waves to travel long kilometres to a receiver, we have to combine it with a “carrier wave”—an electromagnetic wave. 

Electromagnetic waves are made up of oscillating electric and magnetic fields, just like visible light, but radio waves are right down on the lower end of the spectrum, so their wavelengths are very long—around 300 metres. 

(Image Credit: NASA)

Sound information is combined with the wave by altering or modulating the wave’s properties, like changing its amplitude, frequency, or phase. There are two ways to combine the audio signal with the carrier wave: amplitude modulation (AM) or frequency modulation (FM). 

AM radio changes the overall amplitude or strength of the wave, varying its height in order to incorporate the sound information. FM radio works a little differently, because it changes the frequency of the wave rather than the amplitude. The frequency is the number of wavelengths that pass by a given point per second—physically, a high frequency wave would look squashed up, and a low frequency wave would look stretched out. 

(Image Credit: Wikimedia Commons)

Both kinds of waves are susceptible to variations in amplitude as they zoom off through the air, but since FM radio relies on changes in frequency rather than amplitude, these variations don’t matter—they can just be ignored, and so the sound quality is usually super clear. But AM radio relies on the amplitude to convey information, so when the amplitude is varied a bit, this results in interference or static, which will be a familiar idea if you’ve ever listened to AM radio on a rural country road. The upside of AM radio is that it travels much further than FM radio, which is probably why you’re listening to it on that rural country road in the first place. 

So once these radio waves—whether AM or FM—hit a radio receiver, their oscillating fields induce a current in the conductor. The sound information encoded into the waves can be extracted, and converted back to sound waves to grace your ears with your favourite music or talk show. 

(Bonus: if you want to use science to learn more cool science, my fave podcasts are Radiolab, the Infinite Monkey Cage, and Big Picture Science.)

You've Pasted An Image URL Into A Post. What Happens Next Will Shock You.

Copy the URL of an image you own. Paste that URL anywhere in the text of a post. Watch how that URL doesn’t even show up. Watch how — ♫ whap ♫ — your image shows up instead. 

An invisibly delightful convenience. Enjoy. 

What’s the coolest thing you’ve made with code?

Programming drones is probably the funnest thing I've learned so far. Karlie Kloss, #HourOfCode

In just over a week I will be embarking on my most ambitious project since visiting Mount Everest and the fabled Himalayas. Until March I will be exploring the mountains, deserts, seas and cities of the United Arab Emirates. 

It will be a return to photographing the globe and a focus on the geography and culture that resides on the shores of the Persian Gulf. I will be regularly blogging about the country and at the end will have select pieces going into a very exciting exhibition in London that I am apart of. 

Stay tuned for all the Arabian peninsula has to offer, I can’t wait to be back in a desert! 

Freddie Ardley Photography

Check out Freddie’s: Instagram Facebook Website

Marvel & DC Ultralight

By Bunka

An Artist’s Studio Constructed Entirely Out of Cardboard

Tom Burckhardt has fulfilled his childhood fantasy. He constructed a realistic clubhouse entirely out of cardboard! Ordinarily a painter, he built this artist’s studio using only hot glue and black paint, and pieced together a floor, roof, and elaborate work stations. The installation has been touring art museums as an exhibit since its creation in 2005.

Like.

The Burj Khalifa (Downtown Dubai, UAE)

By Freddie Ardley Photography

Check out Freddie’s: Instagram Facebook Website

Tumblr Tuesday: Earth Day

Fursty Photo (furstyphoto) Earth Day is about critical issues facing our planet, but sometimes it’s also about how goddamned beautiful a mountain is. Look. 

Miss Marine Bio (missmarinebio) The ocean is as terrifying as it is amazing, full of sharks and maybe even the ghosts of dead sharks. Lucky for us, Miss Bio is going where few of us are brave enough to go, and she’s taking pictures along the way.

Earth Street (earthstreet) Imagine if someone stopped you on the street, took your picture, and asked you what you thought about the Earth. Caren didn’t have to imagine it. Good job, Caren. 

Exoteric Environmentalism (exotericenvironmentalism) If you’re into cool facts, you’re into this blog. If you’re into dumb lies, we don’t know what to recommend you, but we still respect you.

Marine Conservation (marine-conservation) Now that we all agree ghost sharks exist, please read this blog to educate yourself on man-sized swimming centipedes.  

Landscape via erosion, tectonics, volcanoes, etc. Human via sperm and egg. Photo of landscape via furstyphoto