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This is for you vintage science film buffs: here is a circa 1920 film: How the Telephone Talks (A Silent Film).

This is an educational film from 1920 that explained the “modern” telephone. The concepts are still relevant to today’s modern versions, including the cell phone, which is both radio and telephone.

From Wiki:

A telephone, or phone, is a telecommunications device that permits two or more users to conduct a conversation when they are not in the same vicinity of each other to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals suitable for transmission via cables or other transmission media over long distances, and replays such signals simultaneously in audible form to its user. The word telephone has been adapted into the vocabulary of many languages. It is derived from the Greek: τῆλε, tēle, far and φωνή, phōnē, voice, together meaning distant voice.

First patented in 1876 by Alexander Graham Bell and further developed by many others, the telephone was the first device in history that enabled people to talk directly with each other across large distances. Telephones became rapidly indispensable to businesses, government, and households, and are today some of the most widely used small appliances.

The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice of the distant person. In addition, most telephones contain a ringer which produces a sound to announce an incoming telephone call, and a dial used to enter a telephone number when initiating a call to another telephone. Until approximately the 1970s most telephones used a rotary dial, which was superseded by the modern Touch-Tone push-button dial, first introduced by AT&T in 1963. The receiver and transmitter are usually built into a handset which is held up to the ear and mouth during conversation. The dial may be located either on the handset, or on a base unit to which the handset is connected by a cord containing wires. The transmitter converts the sound waves to electrical signals which are sent through the telephone network to the receiving phone. The receiving telephone converts the signals into audible sound in the receiver, or sometimes a loudspeaker. Telephones are a duplex communications medium, meaning they allow the people on both ends to talk simultaneously.

A landline telephone is connected by a pair of wires to the telephone network, while a mobile phone, such as a cellular phone, is portable and communicates with the telephone network by radio transmissions. A cordless telephone has a portable handset which communicates by radio transmission with the handset base station which is connected by wire to the telephone network.

The telephone network, consisting of a worldwide net of telephone lines, fiber optic cables, microwave transmission, cellular networks, communications satellites, and undersea telephone cables connected by switching centers, allows any telephone in the world to communicate with any other. Each telephone line has an identifying number called its telephone number. To initiate a telephone call the user enters the other telephone’s number into a numeric keypad on the phone.

Although originally designed for simple voice communications, most modern telephones have many additional capabilities. They may be able to record spoken messages, send and receive text messages, take and display photographs or video, play music, and surf the Internet. A current trend is phones that integrate all mobile communication and computing needs; these are called smartphones.

( http://g.nw7us.us/1996vSl )

The other day I received, like some unknown number of others, an invitation to try the QST Digital Edition beta for the May 2012 issue.  I am not a hard-core mobile/digital media user.  But, Sarah is a librarian who has specialized in management and procurement of electronic journals and books.  So, she gave me the low-down on what to look for.  And, over the years, I’ve given her what-for about eBooks because, as I like to say, “I am willing to risk a single print copy of something by taking it places I wouldn’t risk taking an electronic reader.”  That sums up the perspective I took when reviewing e-QST.

You can read about the Digital Edition on ARRL’s FAQ here.  The desktop version requires Flash to use in-browser or Adobe Air and an enormous download to go stand-alone, neither of which really warmed my heart.  But, it does work in the web browser of a mobile device.  I have a 2nd generation iPod Touch running iOS 4 and it worked great in Safari.  I now have a bit of insight as to why people might love their iPads (which I have always viewed as a more-expensive, less-convenient version of the iPod Touch or iPhone).  There appear to be only two levels of zoom: fit page width and zoomed-in.  No matter how good your eyesight, you need to be zoomed in to read because the characters don’t render legibly otherwise.  I think iPad’s larger screen might make reading it easier.

Browsing page thumbnails was OK, but it’s difficult to actually know what you’re looking at before you select the page.  It also would be nice if the pages were numbered in thumbnail view.

One of the big advantages of the Digital Edition is that you can do things you can’t do with the print version, like including audio of JT65.  Granted, I think almost anyone who’s active on HF CW or digital knows what JT65 sounds like, but it’s a basic demonstration of the kinds of things that will be possible in the new format.

Given that I’m usually done with one month’s issue by the time the next one comes out, the Digital Edition is alright for basic browsing and reading.  It’s much faster to skim the print issue, at least with my barebones 768 kbps DSL connection and the higher visual bandwidth of print (read Tufte’s essay The Cognitive Style of PowerPoint for more on this and other interesting reasons to hate slide decks).  The mobile version also requires you to be connected to the Internet to browse.  It turns out that an entire issue is on the order of 350 MB to download stand-alone on a computer.  This makes it difficult to take places where I often want to read QST (on airplanes, for instance)…  It is possible to print from the desktop version (I tried it using 32-bit Windows XP and Firefox), although it seems to be slower than the mobile version (not entirely unexpected).

Another thing that’s a bit different is that if you download the offline content to your desktop, you still need to authenticate to open it.  It’s not clear whether this continues if you drop your ARRL membership.  It is a bit different than owning boxes of back issues…even if you drop your membership, you still have the magazines.  I don’t think this is a huge concern for most hams, who probably wouldn’t be interested in old QSTs if they dropped the membership.

In summary, I like the concept of the Digital Edition, but I wish I could carry off-line issues around on my mobile device.  ARRL hints at this in the FAQ, so I am hopeful.

Saw this in my Google Reader at work and had to post.  Apply to work, ham radio, …?  It’s clearly an artist’s take and not an engineer’s.