eFax How-Tos

How Fax Machines Work

Although fax machines may seem like complicated pieces of hardware, their functionality is actually quite straightforward. Here’s a quick step-by-step process on how they work.

How Do Fax Machines Work?

Simply put, fax machines work by sending digital data through phone lines. A fax machine “reads” the text on a piece of paper, converts it into a sequence of audio tones, and transmits those tones to the receiving fax machine, which then converts it back into text.

The fact that today you might still have a need to send a fax is amazing when you consider that faxing has been around for literally 150 years, easily making it the oldest technology you have in your office. (Unless you do your book keeping with an abacus.)

Granted, you may not even know how to use a fax machine. And today, you can use modernized versions of this 19th century communication technology—you can send a fax online, fax by email, and even fax on your phone with a mobile fax app. But you’ve got to admit: Fax has proven that it has staying power.

So it’s probably worth learning how the underlying technology works, right? It’s actually pretty cool.

How a Fax Machine Reads Your Fax Document

Before your fax machine can transmit your paper document to your recipient’s fax machine, it first needs to “see” the document and record what’s on it.

We use the term “see” because, when you feed your document into a fax machine, it uses a built-in photo sensor to view the page as a series of tiny squares (maybe just a hundredth of an inch each), and then records each square as either black or white. The reason older fax machines often used a rotating drum for paper-feeding was so the machine could record a single line’s worth of these tiny squares at a time, then rotate to the next line.

Once the fax machine has recorded a page’s contents, it converts each of the squares into a sequence of audio tones, using different tones to signify that a square is either white or black. (Cool, huh?)

With the page’s info recorded on your fax machine, now it’s ready to transmit.

How a Fax Machine Sends Your Fax

To send your fax, your fax machine (in most cases) actually uses the plain-old telephone network. When you dial your recipient’s fax number on the machine’s keypad, and the two machines connect, your machine starts sending those audio tones over phone lines.

This is what you’re hearing as your fax machine makes those horrible screeching and beeping noises. It’s screaming to your recipient’s fax machine, telling it what to print: “Black square! White square! Black! Black! White, white, white! Black, white, black!”

In other words, you’ve probably listened to many of your faxes translated into “telephone-ese” without ever realizing it.

See How Easy It Is To Fax Your Documents

Although fax machines may seem like complicated pieces of hardware, their functionality is actually quite straightforward. Here’s a quick step-by-step process on how they work:
Step-by-Step Breakdown of How Fax Machines Work

To start faxing, you first need to prepare or scan the document you wish to transmit. Typically, this is achieved using a computer or a digital scanner.

Documents are converted into a digital signal made up of 0s and 1s so that the information can be transmitted over a standard phone line.

After the document is prepared, the fax machine is set up with the recipient’s fax number or email, as well as a cover letter.

After the fax is prepared and submitted, the fax machine will dial the recipient’s number and transmit the digital signal to another fax machine.

The receiving fax machine decodes the digital signal and reconstructs the document. The document is then printed out on the receiving end.

Faxing is Still a Relevant and Convenient Form of Communication

In spite of the increasing popularity of email and digital messaging, faxing is still a great tool for sending documents quickly and securely. With the growing popularity of cloud-based faxing services, faxing is also now more convenient and accessible than ever. These online faxing services offer affordable options for both personal and business use, making them highly scalable. Additionally, they provide features such as document storage, digital signatures, and even mobile faxing options.

Even without a traditional phone line, you can take advantage of the convenience offered by online faxing solutions like eFax. With eFax, you can send faxes from anywhere with an internet connection, whether through your laptop, tablet, or even your smartphone. This allows you to send important documents from any internet-enabled device you want, freeing you from the physical restrictions of a fax machine.

Using online fax services, you get to keep all your faxes securely stored in the cloud, which means you no longer have to concern yourself with depleting paper or toner supplies. This convenience allows for quick retrieval of previously sent or received documents, saving you from sifting through piles of paper files. Solutions like eFax offer unlimited cloud storage with all subscription plans, freeing you from the hassles of long-term contracts and the recurring costs associated with maintaining a traditional fax machine and a separate phone line.

Traditional fax machines can be time-intensive and cumbersome. Switching to online faxing streamlines your fax management, making the process much more efficient. It eliminates the steps of printing, manually operating the fax machine, and waiting for fax transmissions. With online faxing solutions like eFax, you send dispatch multiple faxes at once with just a few clicks from your mobile device. Try eFax today to experience the simplicity and efficiency of managing your faxes online.

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Your Faxing Doesn’t Have to Work This Way

Technology has come a long way since the 1840s, when the first fax device was invented—and since the 1980s, when the analog fax machines we described above went into widespread use in business.
So you can keep faxing like it’s 1989, standing over your desktop fax machine, waiting for it to finish screaming, “White square! Black square!”
Or you can ditch the machine altogether—and start faxing online, from anywhere.

Related FAQs

No, with online fax services like eFax, a traditional phone line isn’t necessary. As long as you have an internet connection, you can send faxes directly from your device.

Fax machines work by transforming a document into digital signals and sending them over a phone line to another fax machine. The receiving machine then decodes these signals and produces a printed copy of the document.

Definitely. With online fax services like eFax, you can easily send faxes from your computer or any internet-enabled device, eliminating the need for a traditional fax machine or phone line.

Yes, it is. With services like eFax, you have the capability to get faxes straight to your email inbox, which makes it easier to manage and store your documents for later use.

eFax provides an email notification once your fax has been sent successfully. This feature allows you to efficiently track your sent faxes and confirm their receipt by the recipient.