Reference

The U.S. Food and Drug Administrationís Center for

Devices and Radiological Health Consumer

Update on Mobile Phones

FDA has been receiving inquiries about the safety of mobile phones, including cellular phones and PCS phones. The follow- ing summarizes what is known--and what remains unknown-- about whether these products can pose a hazard to health, and what can be done to minimize any potential risk. This informa- tion may be used to respond to questions.

Why the concern?

Mobile phones emit low levels of radiofrequency

energy (i.e., radiofrequency radiation) in the microwave range while being used. They also emit very low levels of radiofre- quency energy (RF), considered non-significant, when in the stand-by mode. It is well known that high levels of RF can pro- duce biological damage through heating effects (this is how your microwave oven is able to cook food). However, it is not known whether, to what extent, or through what mechanism, lower levels of RF might cause adverse health effects as well. Although some research has been done to address these questions, no clear picture of the biological effects of this type of radiation has emerged to date. Thus, the available science does not allow us to conclude that mobile phones are absolutely safe, or that they are unsafe. However, the available scientific evidence does not demonstrate any adverse health effects associated with the use of mobile phones.

What kinds of phones are in question?

Questions have been raised about hand-held mobile phones, the kind that have a built-in antenna that is positioned close to the user's head during normal telephone conversation. These types of mobile phones are of concern because of the short distance between the phone's antenna--the primary source of the RF--and the person's head. The exposure to RF from mobile phones in which the antenna is located at greater distances from the user (on the outside of a car, for example) is drastically lower than that from hand-held phones, because a person's RF exposure decreases rapidly with distance from the source. The safety of so-called "cordless phones," which have a base unit connected to the telephone wiring in a house and which operate at far lower power levels and frequencies, has not been questioned.

How much evidence is there that hand-held mobile phones might be harmful?

Briefly, there is not enough evidence to know for sure, either way; however, research efforts are on-going. The existing sci- entific evidence is conflicting and many of the studies that have been done to date have suffered from flaws in their research methods. Animal experiments investigating the effects of RF exposures characteristic of mobile phones have yielded

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Motorola MicroTAC owner manual Why the concern?

MicroTAC specifications

The Motorola MicroTAC, introduced in 1989, is an iconic mobile phone that set the stage for the evolution of modern cellular technology. Known for its innovative design, the MicroTAC was one of the first truly portable mobile phones, demonstrating how far telecommunications had come since the bulky models of earlier decades.

One of the standout features of the MicroTAC was its flip design, which allowed the phone to be compact when closed and easy to carry. When opened, the phone revealed a numeric keypad and a small monochrome display, which provided essential functions and caller ID information. This flip mechanism not only contributed to its portability but also protected the keypad and screen from damage when not in use.

The MicroTAC was notable for its lightweight plastic casing, which made it significantly lighter than its contemporaries. Weighing just under 250 grams, it was a remarkable feat of engineering at the time. The phone had a unique “antenna-in-handle” design, which contributed to its sleek appearance while also optimizing signal reception. This innovation was part of Motorola’s effort to make mobile communication accessible and convenient.

In terms of battery life, the MicroTAC featured a rechargeable NiCd battery that provided several hours of talk time. While modern smartphones boast days of battery life, the MicroTAC was considered admirable for its time, allowing users the freedom to communicate on the go without frequent recharges.

The Motorola MicroTAC operated on analog networks, specifically using the Advanced Mobile Phone System (AMPS). This technology allowed for a clearer voice transmission and was crucial in the early days of mobile communication, enabling users to connect in various environments where fixed lines were impractical.

Additionally, the MicroTAC boasted features like call waiting, auto redial, and a phone book capable of storing multiple contacts—a considerable leap forward from earlier mobile devices.

Despite its simplicity compared to modern smartphones, the Motorola MicroTAC laid the groundwork for future mobile technologies and design principles. Its combination of portability, innovative engineering, and user-friendly features solidified Motorola's reputation as a leader in telecommunications. The MicroTAC remains a nostalgic symbol of the early mobile telephony era and a testament to the foundational technologies that paved the way for today's devices.