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The Consumer Electronics Hall of Fame: Motorola Advisor Pager

This was the first product that let you reach a doctor when you absolutely, positively needed one

2 min read
photo of the Motorola Advisor Pager
Good Advice: The Motorola Advisor, which came out in 1990, was among the first pagers capable of displaying alphanumeric text.
Photo: Motorola

In the early 1990s, when pagers were in their heyday, the Motorola Advisor was the pager of choice.

The first paging systems were introduced in the 1950s, but pagers came into widespread use only in the 1980s, when wireless technology got good enough to make them easy to use. At the time, Motorola was practically synonymous with wireless communications technology.

The early pagers were far smaller, lighter, and more portable than the cellular phones of the day, which were called bricks for good reason. Typical pager customers wore the devices on their hips and worked in medicine, emergency care, and other quick-response professions.

Early pagers mostly lacked screens, which meant that responding to a page required two calls. When the unit buzzed or beeped, users had to go find a phone, inevitably a landline. They’d first call a pager service to get the phone number the caller had left, and then call the caller.

Pager makers tried several approaches to avoid this problem. Some built models that would allow callers to leave a voice message that could be stored on the pager and played back by the user. Others incorporated tiny screens that could display either a phone number or a numerical code. People compiled lists of codes they would share with callers and other pager users. In this one, 41 means “call me,” for example, and 53 means “thank you,” and so on.

By the early 1990s, roughly 3 million people were using pagers, by some estimates. Many of the new customers had merely a desire rather than a need to be constantly in touch—executives, for instance. By 1993 Motorola’s user manual for the Advisor II noted that the product was “ideal for demanding business environments.”

The original Advisor, released in 1990, was among the first pagers to provide alphanumeric messaging—up to four lines of text with up to 20 characters per line. It could be set to receive not only individual pages but also up to three additional group pages. It also included an alarm clock function. It was compact, measuring 18.5 by 55 by 81 millimeters, and ran on a single AA battery. 

Alphanumeric messaging unlocked the full potential of the pager. Often you could send enough information in one 80-character message to ensure that no callback was required. In retrospect, it could be considered a prototype for text messaging, with the same advantages of utility, convenience, and brevity. In the mid-1990s, the number of people using the devices skyrocketed, with estimates ranging from about 25 million to 61 million.

Motorola made two Advisor models that could communicate on different combinations of UHF, VHF, and 900-megahertz bands (the frequency was user selectable). They offered at-the-time blazing fast transmission rates of 1600, 3200, or 6400 baud. The communications protocol was a one-way system called Flex; it was created by Motorola and used primarily for its pagers (a later version, called ReFlex, was two-way). The Advisor’s user manual helpfully suggested, “Include your pager number on business cards and on your answering machine message.” Wow. Remember answering machines?

A few years later, smartphones—and actual text messaging—began to supersede pagers. Nevertheless, paging lives on. To this day, some doctors still use them, because their messages are more secure and their transmission is more reliable.

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Caltech Team Launches Experimental Space-Based Solar Array

The satellite will test some of the tech needed to wirelessly beam power from orbit

4 min read
A lightweight gold-colored square frame for a solar power array, seen flying in space with Earth in background.

Artist's conception of Caltech's Space Solar Power Demonstrator in Earth orbit.


For about as long as engineers have talked about beaming solar power to Earth from space, they’ve had to caution that it was an idea unlikely to become real anytime soon. Elaborate designs for orbiting solar farms have circulated for decades—but since photovoltaic cells were inefficient, any arrays would need to be the size of cities. The plans got no closer to space than the upper shelves of libraries.

That’s beginning to change. Right now, in a sun-synchronous orbit about 525 kilometers overhead, there is a small experimental satellite called the Space Solar Power Demonstrator One (SSPD-1 for short). It was designed and built by a team at the California Institute of Technology, funded by donations from the California real estate developer Donald Bren, and launched on 3 January—among 113 other small payloads—on a SpaceX Falcon 9 rocket.

“To the best of our knowledge, this would be the first demonstration of actual power transfer in space, of wireless power transfer,” says Ali Hajimiri, a professor of electrical engineering at Caltech and a codirector of the program behind SSPD-1, the Space Solar Power Project.

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Building the Future of Smart Home Security

Engineers must invent new technology to enhance security products’ abilities

4 min read
One engineer peers into a microscope to work on a small circuit while another engineer looks on

In this article, SimpliSafe’s VP of Software Engineering discusses his team’s focus on creating a safer future through enhanced technology.


This is a sponsored article brought to you by SimpliSafe.

It’s nearly impossible to find a household today that doesn’t have at least one connected smart home device installed. From video doorbells to robot vacuums, automated lighting, and voice assistants, smart home technology has invaded consumers’ homes and shows no sign of disappearing anytime soon. Indeed, according to a study conducted by consulting firm Parks Associates, smart home device adoption has increased by more than 64 percent in the past two years, with 23 percent of households owning three or more smart home devices. This is particularly true for devices that provide security with 38 percent of Americans owning a home security product. This percentage is likely to increase as 7 in 10 homebuyers claimed that safety and security was the primary reason, after convenience, that they would be seeking out smart homes, according to a report published by last year.

As the demand for smart home security grows, it’s pertinent that the engineers who build the products and services that keep millions of customers safe continue to experiment with new technologies that could enhance overall security and accessibility. At SimpliSafe, an award-winning home security company based in Boston, Mass., it is the pursuit of industry-leading protection that drives the entire organization to continue innovating.

In this article, Nate Wilfert, VP of Software Engineering at SimpliSafe, discusses the complex puzzles his team is solving on a daily basis—such as applying artificial intelligence (AI) technology into cameras and building load-balancing solutions to handle server traffic—to push forward the company’s mission to make every home secure and advance the home security industry as a whole.

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