File:Recreational Walkie Talkies.jpg

Recreational_Walkie_Talkies.jpg (640 × 480像素,文件大小:105 KB,MIME类型:image/jpeg


摘要

描述
English: A collection of walkie-talkies, handheld portable two-way radios for recreational use. From left:
  • Motorola FRS radio, purchased in 2002, which operates on the Family Radio Service band.
  • Motorola dual band walkie-talkie, purchased in 2004, which can operate on either the FRS or the General Mobile Radio Service (GMRS) channels. On both these radios, the antenna is permanently attached, as required by FCC regulations for FRS gear.
  • Early 1980s amateur radio transceiver for the 2 meter (144 MHz) band, complete with external speaker-mike, and DTMF keypad for remote repeater control and phone patch operation.
  • Smaller amateur transciever for the 2 meter (144 MHz) and 70 cm (428 MHz) bands. Although similar in size to the smaller FRS units, it is much more versatile, has a higher transmit power, and can transmit on any of several hundred frequencies in two Amateur radio bands.
  • A 1960s vintage toy walkie-talkie operating in the 27 MHz Citizens' Band; its 900 mm (36 inch)whip antenna is partly extended. This unit has a superheterodyne receiver, and 10 transistors.
  • A mid-1980's toy walkie-talkie operating at very low power in the 49 MHz band, with a Morse code key and the Morse code printed on the case. This unit has only 4 transistors and no volume control or squelch. In addition, rather than the telescoping whip antenna common on earlier models, this unit has a rubber duck antenna, which is thought to be more robust and less dangerous to the user if broken, and has replaced telescoping antennas in virtually all children's two-way radio units.

Commercial and emergency services walkie-talkies may be similar in size to the amateur units shown here, but generally have much better battery life, more rugged construction, and simpler controls, often restricting operation to only one or a few pre-programmed channels. In addition, many have ruggedizing features such as waterproofing (especially for outdoors and marine use) and intrinsically safe design for use in fire-prone industrial environments.

The two older walkie-talkies on the right use only discrete transistors; all the more recent ones shown here use microprocessors and integrated circuits for most of their functions.
日期 2005年4月21日 (原始上传日期)
来源 本檔案是由Premeditated Chaos使用CommonsHelper,從en.wikipedia轉移到維基共享資源。
作者 英语维基百科Wtshymanski

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  • 2005-04-21 04:01 Wtshymanski 640×480× (107183 bytes) {pd} Recreational walkie-talkies. From the left: two different models of [[FRS]] radios by Motorola. Third from the left an early 1980's [[amateur radio]] radio for the [[2 metre]] band, complete with external speaker-mike, and [[DTMF]] keypad for remote

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Recreational, toy and amateur radio walkie-talkies

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当前2012年1月19日 (四) 22:372012年1月19日 (四) 22:37版本的缩略图640 × 480(105 KB)File Upload Bot (Magnus Manske) {{BotMoveToCommons|en.wikipedia|year={{subst:CURRENTYEAR}}|month={{subst:CURRENTMONTHNAME}}|day={{subst:CURRENTDAY}}}} {{Information |Description={{en|'''Recreational walkie-talkies.''' From the left: two different models of personal two-way radios by

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