{"id":33,"date":"2022-03-14T11:20:21","date_gmt":"2022-03-14T02:20:21","guid":{"rendered":"https:\/\/ad124asbtu.smartrelease.jp\/jp\/?page_id=33"},"modified":"2025-04-03T14:28:15","modified_gmt":"2025-04-03T05:28:15","slug":"exhibitionhall","status":"publish","type":"page","link":"https:\/\/yrp.co.jp\/en\/exhibitionhall\/","title":{"rendered":"Exhibition hall"},"content":{"rendered":"\n<h2 class=\"wp-block-heading has-text-align-center is-style-default\"><strong>Exhibition Room <\/strong><br>on History of Wireless Communications<\/h2>\n\n\n\n<p>In order to further deepen the understanding of the history of wireless communication, the Exhibition Room was opened with the cooperation of exhibitors, mainly companies of the Yokosuka Research Park (YRP).\u3000Please take this opportunity to visit and see the achievements of our predecessors in the field of wireless communication technology.<\/p>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-box epb-box is-style-epb-radius__3 epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet is-style-epb-default\"><div class=\"epb-box__headline\" data-fontweight=\"normal\" style=\"text-align:left;background-color:#023a8f;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:17px;line-height:1;letter-spacing:0.1em;color:#ffffff\">Contents list<\/div><div class=\"epb-box__body\" style=\"padding:16px;background-color:#ffffff;border-style:none;border-color:#828990;border-width:2px\">\n\n<h2 class=\"wp-block-heading has-normal-font-size\"><a href=\"#info\">User guide<\/a><\/h2>\n\n\n<h2 class=\"wp-block-heading has-normal-font-size\">Exhibition information<\/h2>\n\n\n<ol class=\"wp-block-list\">\n\n<li><a href=\"#one\" data-type=\"URL\">Introduction to Yokosuka Research Park<\/a><\/li>\n\n\n<li><a href=\"#two\">History of Yokosuka<\/a><\/li>\n\n\n<li><a href=\"#wireress\">Advent of Radio Communications<\/a><\/li>\n\n\n<li><a href=\"#radio\">Beginning of Radio Broadcasts<\/a><\/li>\n\n\n<li><a href=\"#radio-valve\">Development and History of Vacuum Tubes<\/a><\/li>\n\n\n<li><a href=\"#Wireless-communication-device\">Evolutionary History of Radio Communication Equipment<\/a><\/li>\n\n\n<li><a href=\"#cellphone\">Advent and History of Mobile Phones<\/a><\/li>\n\n<\/ol>\n\n\n<h2 class=\"wp-block-heading has-normal-font-size\"><a href=\"#link\">Links<\/a><\/h2>\n\n\n<h2 class=\"wp-block-heading has-normal-font-size\"><a href=\"#access\">Access<\/a><\/h2>\n\n<\/div><\/div>\n\n\n\n<div style=\"height:47px\" aria-hidden=\"true\" id=\"info\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-box epb-box is-style-epb-radius__3 epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet is-style-epb-default\"><div class=\"epb-box__headline\" data-fontweight=\"bold\" style=\"text-align:left;background-color:#023a8f;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:24px;line-height:1;letter-spacing:0.05em;color:#f2f3f3\">User guide<\/div><div class=\"epb-box__body\" style=\"padding:16px;background-color:#ffffff;border-style:none;border-color:#80b5dd;border-width:2px\">\n\n<p class=\"has-normal-font-size\">For groups of 10 or more, please apply at least 2 weeks before the desired date.<br>Explanation guide (only in Japanese) provided.<\/p>\n\n\n<p>Admission fee:  free<\/p>\n\n\n<p>Visiting hours:  Weekdays 10:00 am to 5:00 pm<br>\uff08We may not be able to accommodate you on some days for an unavoidable reason.\uff09<\/p>\n\n\n<p>Please note that due to the limited number of acceptable visitors, we may not be able to meet your request.<br>In addition, when events, etc. are held at YRP, individuals may be able to view them.<br>Please use the email form below to inquire about schedules, etc.<\/p>\n\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-button epb-button epb-alignment-center epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" data-button-size=\"m\"><div class=\"epb-btn-size__m\" style=\"--epb-button-text-font-sp:14px;--epb-button-text-font-tablet:14px;--epb-button-text-font-pc:19px;--epb-microcopy-top-font-sp:12px;--epb-microcopy-top-font-tablet:12px;--epb-microcopy-top-font-pc:15px;--epb-microcopy-bottom-font-sp:12px;--epb-microcopy-bottom-font-tablet:12px;--epb-microcopy-bottom-font-pc:12px\"><a style=\"--epb-button-bg-color:#d8dbd9;--epb-button-border-color:#d8dbd9;--epb-button-border-size:1px\" class=\"epb-btn epb-btn__outline is-style-epb-radius__25 is-style-epb-button__standard is-style-epb-hover__opacity\" href=\"https:\/\/www.yrp.co.jp\/en\/aboutyrpinc\/inquiry\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span class=\"epb-btn-text icon-mail\" data-fontweight=\"bold\" style=\"line-height:1;letter-spacing:0.03em\">Contact us<\/span><\/a><\/div><\/div>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-headling epb-advance-headling is-style-epb-block-radius__0 epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"background:#023a8f;--epb-font-sp:26px;--epb-font-tablet:26px;--epb-font-pc:30px;--epb-style-color:#023a8f;--epb-subtext-label-height:1em;--epb-subtext-label-width:1em;--epb-headling-background-color:#023a8f;--epb-block-padding-top:0;--epb-block-padding-bottom:0;--epb-block-padding-left:0;--epb-block-padding-right:0\" id=\"one\"><div class=\"epb-advance-headling__text-wrapper is-style-epb-headling-default epb-has-background epb-has-sub-text-under\"><h2 class=\"epb-advance-headling__text\" data-fontweight=\"bold\" style=\"line-height:1.6;letter-spacing:0.46em;color:#ffffff\">Exhibition information<\/h2><\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">\uff11\uff0e<span class=\"epb-underline-blue\">Introduction to Yokosuka Research Park<\/span><\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"661\" height=\"371\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/ex01-view.jpg\" alt=\"\" class=\"wp-image-2381\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/ex01-view.jpg 661w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/ex01-view-300x168.jpg 300w\" sizes=\"auto, (max-width: 661px) 100vw, 661px\" \/><\/figure>\n\n\n\n<p>Yokosuka Research Park (YRP) is a research cluster established in 1997 to unify international standards on mobile phones. &nbsp;Public research institutions, laboratories of universities as well as leading corporations of Japan and abroad came together at YRP and developed the third generation mobile phone in 2001. In conducting radio wave experiments, interference of radio waves from and to urban areas must be avoided.&nbsp; This location was selected because of the site conditions as a through area surrounded by hills with favorable access to central Tokyo. One of the most advanced and leading research and development activities in Japan is promoted in an environment rich with nature surrounded by the ocean and greenery.<\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" id=\"two\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">\uff12\uff0e<span class=\"epb-underline-blue\">History of Yokosuka<\/span><\/h2>\n\n\n\n<p>In 1854, Commodore Perry landed on Kurihama Beach in Yokosuka and requested Japan to open the country to the world. &nbsp;At that time, Perry presented two units of telegraph equipment to the shogunate government and the Emperor. &nbsp;The intention of these gifts was to show how the world had steadily built telegraph networks as shown in the figure below.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"508\" height=\"245\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/11p.png\" alt=\"\" class=\"wp-image-2380\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/11p.png 508w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/11p-300x145.png 300w\" sizes=\"auto, (max-width: 508px) 100vw, 508px\" \/><figcaption class=\"wp-element-caption\">A depiction of Perry\u2019s landing at Kurihama Beach<br>A Heine painting, courtesy of Yokosuka City Museum<\/figcaption><\/figure>\n\n\n\n<p>In 1850, the telegraph network crossed the Strait of Dover with undersea cables for the first time in the world. The undersea cables then crossed the Atlantic Ocean in 1866, and it signified the era in which telegraphic communications connected Europe, Asia, South and North America, Africa, Southeast Asia, Australia, and New Zealand. &nbsp;Japan was not a part of this telegraph network and needed to pour all its efforts into closing this technology gap<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"982\" height=\"411\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/12p.png\" alt=\"\" class=\"wp-image-2379\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/12p.png 982w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/12p-300x126.png 300w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/12p-768x321.png 768w\" sizes=\"auto, (max-width: 982px) 100vw, 982px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2023\/02\/blue.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">Land Telegraph Network<\/span><\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2023\/02\/yellow.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">Undersea Cable Telegraph Network of the world<\/span><br> <span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">in 1866.<\/span><\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<p><\/p>\n\n\n\n<p>In 1889, to respond to the Southward Expansion Policy of Russia, Japan placed orders for battleships with the United Kingdom, and Battleship Mikasa, which is&nbsp; preserved as Memorial Ship Mikasa in Yokosuka port area, was one of such vessels.&nbsp;<br>Shortly after placing these orders, Guglielmo Marconi successfully performed a radio communications experiment in 1895 and gradually extended the range.<br>Up to that point, the communication method for ships at sea were limited to flag semaphore or blinking lights with a communication range of, at most, 40 kilometers.<br>The world understood that radio communications was essential for battleships.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"495\" height=\"284\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/03.jpg\" alt=\"\" class=\"wp-image-2383\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/03.jpg 495w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/03-300x172.jpg 300w\" sizes=\"auto, (max-width: 495px) 100vw, 495px\" \/><figcaption class=\"wp-element-caption\">Battleship Mikasa arriving in Japan<br>Photograph courtesy of the Mikasa Preservation Society<\/figcaption><\/figure>\n\n\n\n<div style=\"height:55px\" aria-hidden=\"true\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<p>Japan therefore negotiated with Marconi to purchase his radio communication equipment, but the price was so outrageous that they had no choice but to engage in their own development. Efforts were made by Senior Researcher Matsushiro of the Electrotechnical Laboratory and Professor Kimura of the former Daini Senior High School (under the prewar education system) which later became Tohoku University, and, in 1897, they successfully completed the first radio experiment off the shore of Shinagawa, Tokyo.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:50%\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"557\" height=\"331\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/13p-2.png\" alt=\"\" class=\"wp-image-2386\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/13p-2.png 557w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/13p-2-300x178.png 300w\" sizes=\"auto, (max-width: 557px) 100vw, 557px\" \/><figcaption class=\"wp-element-caption\">Radio telegraph equipment used in the experiment<br>&nbsp;of Tsukishima in Tokyo in 1897<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/14p.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Senior Researcher<br>M. Matsushiro,<br>Electrotechnical Laboratory<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/15p.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Professor<br>S. Kimura,<br>Daini Senior<br>High School<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div style=\"height:45px\" aria-hidden=\"true\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<p>Marconi, at the same time, continued to extend his communication range, and he succeeded in crossing the Strait of Dover, a range of 50km, in 1899. &nbsp;The Japanese Navy also commenced their radio equipment development with an aim of achieving a communication range of 100 kilometers. &nbsp;An experiment was conducted in 1900 between Tsudanuma of Chiba Prefecture and Otsu in Yokosuka, a range of 54 kilometers.<\/p>\n\n\n\n<p>However, extending the communication range remained difficult, and it was compounded by the instability of communication itself.&nbsp; To cope with this situation, the Japanese Navy decided to gather communication engineers at the Naval Arsenal located at Taura (Funakoshi), Yokosuka, in 1902 to engage in radio equipment development.&nbsp; As a result, the Model 36 radio was created in 1903, the year 36 of Meiji Era, and it achieved a communication range of 1,000 kilometers.&nbsp; The Navy immediately constructed a radio factory, and the manufacturing work was carried out day and night to equip all their vessels with Model 36 radio.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"423\" height=\"289\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/02.jpg\" alt=\"\" class=\"wp-image-2387\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/02.jpg 423w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/02-300x205.jpg 300w\" sizes=\"auto, (max-width: 423px) 100vw, 423px\" \/><figcaption class=\"wp-element-caption\">The Building of Yokosuka Naval Arsenal<br>(Currently existed as a building of Toshiba Lighting &amp; Technology Corporation)<\/figcaption><\/figure>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<p>Yokosuka was selected as the location for the development of radio equipment because it was the center of heavy industries in Japan at the time, with shipbuilding yards and steel mills established in the final days of the shogunate, followed by the establishment of a military port and a weapons factory. It was expected that a variety of knowledge and technologies were available there.<\/p>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-broken-grid epb-broken-grid has-media-on-the-left has-mobile-aligned-image is-style-default epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"padding-top:0;padding-bottom:0;padding-left:0;padding-right:0\"><div class=\"epb-broken-grid__background is-vertically-aligned-top is-horizontally-aligned-left\" style=\"--epb-bg-vertical-sp:0%;--epb-bg-vertical-tablet:0%;--epb-bg-vertical:0%;--epb-bg-horizontal-sp:0%;--epb-bg-horizontal-tablet:0%;--epb-bg-horizontal:0%\"><\/div><div class=\"epb-broken-grid__media\"><div class=\"epb-broken-grid__media--inner epb-broken-grid__media--sell is-style-epb-radius__0\" style=\"--epb-opacity:0.2;--epb-image-vertical-sp:0px;--epb-image-vertical-tablet:0px;--epb-image-vertical:10px;--epb-image-horizontal-sp:0%;--epb-image-horizontal-tablet:0%;--epb-image-horizontal:0%\"><div class=\"epb-broken-grid__media--background\" style=\"transform:translate(2%, 2%);width:100%;height:100%\"><\/div><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/16-e1655355953196.png\" class=\"wp-image-undefined\"\/><\/div><\/div><div class=\"epb-broken-grid__content\" style=\"z-index:1;--epb-content-padding-top-sp:16px;--epb-content-padding-bottom-sp:16px;--epb-content-padding-left-sp:16px;--epb-content-padding-right-sp:16px;--epb-content-padding-top-tablet:16px;--epb-content-padding-bottom-tablet:16px;--epb-content-padding-left-tablet:16px;--epb-content-padding-right-tablet:16px;--epb-content-padding-top:16px;--epb-content-padding-bottom:16px;--epb-content-padding-left:16px;--epb-content-padding-right:16px;--epb-content-vertical-sp:0px;--epb-content-vertical-tablet:0px;--epb-content-vertical:200px;--epb-content-horizontal-sp:0%;--epb-content-horizontal-tablet:0%;--epb-content-horizontal:0%;--epb-content-border-type:solid;--epb-content-border-radius:0;--epb-content-border-width:3px\"><div class=\"epb-broken-grid__content--inner epb-broken-grid__content--m\">\n\n<div class=\"wp-block-emanon-premium-blocks-headling epb-advance-headling is-style-epb-block-radius__0 epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-font-sp:26px;--epb-font-tablet:26px;--epb-font-pc:26px;--epb-style-color:#333333;--epb-subtext-label-height:1em;--epb-subtext-label-width:1em;--epb-headling-background-color:#ffffff;--epb-block-padding-top:0;--epb-block-padding-bottom:0;--epb-block-padding-left:0;--epb-block-padding-right:0\"><div class=\"epb-advance-headling__text-wrapper is-style-epb-headling-default epb-has-sub-text-under\"><h2 class=\"epb-advance-headling__text\" data-fontweight=\"bold\" style=\"line-height:1.6;letter-spacing:0.05em;color:#333333\"><\/h2><\/div><\/div>\n\n\n<p>\u5de6\uff1a\u6c5f\u6238\u5e55\u5e9c\u52d8\u5b9a\u5949\u884c\u5c0f\u6817\u4e0a\u91ce\u4ecb\u5fe0\u9806\u50cf<br>\u53f3\uff1a\u30d5\u30e9\u30f3\u30b9\u6d77\u8ecd\u5927\u6280\u5e2b \u6a2a\u9808\u8cc0\u88fd\u9244\u6240\u9996\u9577 F.L.\u30f4\u30a7\u30eb\u30cb\u30fc\u50cf<\/p>\n\n\n<p class=\"has-text-align-right\">\u51fa\u5178\uff1a\u6a2a\u9808\u8cc0\u5e02\u53f2 \u4e0a\u5dfb<\/p>\n\n\n<p class=\"has-text-align-right\">\u63d0\u4f9b\uff1a\u6a2a\u9808\u8cc0\u5e02<\/p>\n\n<\/div><\/div><\/div>\n\n\n\n<p class=\"has-text-align-right\"><\/p>\n\n\n\n<p>These events led to the telegram transmitted with the Model 36 radio from the merchant cruiser Shinano -Maru at the start of the Battle of Tsushima, on May 27, 1905.&nbsp; When identifying the Russian Baltic Fleet, a telegram of &#8220;Enemy vessel seen&#8221; was&nbsp; sent and relayed by the Battleship Itsukushima&nbsp; and finally received by the Flagship Mikasa, which succeeded in making the first move in the naval battle.&nbsp; This became the driving force behind their crushing victory.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"604\" height=\"431\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/17.png\" alt=\"\" class=\"wp-image-2391\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/17.png 604w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/17-300x214.png 300w\" sizes=\"auto, (max-width: 604px) 100vw, 604px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">Image of the Battle of Tsushima<br>and the bridge on Flagship Mikasa<\/span><br>Photograph courtesy of the Mikasa Preservation Society<\/figcaption><\/figure>\n\n\n\n<p><\/p>\n\n\n\n<p>Yokosuka thus became the center of heavy industries in Japan and made contributions toward the building of superships.&nbsp; However, as the trend of the times changed,&nbsp; in 1975, the gantry crane at Shioiri, which had been indispensable for the town of shipbuilding and had been a landmark of Yokosuka, was removed.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"518\" height=\"350\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/18.png\" alt=\"\" class=\"wp-image-2390\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/18.png 518w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/18-300x203.png 300w\" sizes=\"auto, (max-width: 518px) 100vw, 518px\" \/><figcaption class=\"wp-element-caption\">Gantry crane in Shioiri, Yokosuka<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"537\" height=\"331\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/04.jpg\" alt=\"\" class=\"wp-image-2389\" style=\"width:374px;height:230px\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/04.jpg 537w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/04-300x185.jpg 300w\" sizes=\"auto, (max-width: 537px) 100vw, 537px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"10px\" style=\"font-size:10px;\" class=\"epb-font-size\">Yokosuka Research and Development Center of Nippon Telegraph and Telephone Public Corporation<\/span><\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" id=\"wireress\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\"><span class=\"epb-underline-blue\">\uff13\uff0eAdvent of Radio Communications<\/span><\/h2>\n\n\n\n<p>An Italian inventor, Guglielmo Marconi, succeeded in communicating via radio wave in 1895. Radio communications brought about dramatic progress toward communications between ships, which could not be linked with cables.\u3002<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"348\" height=\"279\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/06.jpg\" alt=\"\" class=\"wp-image-2396\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/06.jpg 348w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/06-300x241.jpg 300w\" sizes=\"auto, (max-width: 348px) 100vw, 348px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"405\" height=\"228\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/07.jpg\" alt=\"\" class=\"wp-image-2395\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/07.jpg 405w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/07-300x169.jpg 300w\" sizes=\"auto, (max-width: 405px) 100vw, 405px\" \/><figcaption class=\"wp-element-caption\">Induction coil, a key component of a transmitter<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/08.jpg\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Coherer wave detector, a key component of a receiver<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<p>The Model 36 radio communications terminal developed by Matsunosuke Matsushiro and Shunkichi Kimura, which was a driving force behind the victory at the Battle of Tsushima, is currently exhibited in the Memorial Ship Mikasa, preserved in Yokosuka.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"456\" height=\"307\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/19.png\" alt=\"\" class=\"wp-image-2393\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/19.png 456w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/19-300x202.png 300w\" sizes=\"auto, (max-width: 456px) 100vw, 456px\" \/><figcaption class=\"wp-element-caption\">Memorial Ship Mikasa<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"402\" height=\"305\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/20.jpg\" alt=\"\" class=\"wp-image-2392\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/20.jpg 402w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/20-300x228.jpg 300w\" sizes=\"auto, (max-width: 402px) 100vw, 402px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"12px\" style=\"font-size:12px;\" class=\"epb-font-size\">Radio Communication Room inside Memorial Ship Mikasa<\/span><\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" id=\"radio\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\"><span class=\"epb-underline-blue\">\uff14\uff0eBeginning of Radio Broadcasts<\/span><\/h2>\n\n\n\n<p>A rich number of vacuum tube radios were manufactured and popularized in the United States, where radio broadcasting began in 1923.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"461\" height=\"218\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/09.jpg\" alt=\"\" class=\"wp-image-2399\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/09.jpg 461w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/09-300x142.jpg 300w\" sizes=\"auto, (max-width: 461px) 100vw, 461px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">Six-tube autodyne type receiver<br>(Manufactured by Atwater Kent Manufacturing Company of the United States)<\/span><\/figcaption><\/figure>\n\n\n\n<p>In 1923, Japan was struck by the Great Kanto Earthquake, which claimed 100,000 lives. The importance of radio broadcasting was reassessed, and the Japan Broadcasting Corporation or NHK (Station JOAK) began radio broadcasting two years later, in 1925. As vacuum tubes were quite expensive at the time, many people listened to radio broadcasts using thin wire crystal detector radio equipment.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"393\" height=\"293\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/20.png\" alt=\"\" class=\"wp-image-2398\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/20.png 393w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/20-300x224.png 300w\" sizes=\"auto, (max-width: 393px) 100vw, 393px\" \/><figcaption class=\"wp-element-caption\">A small wire \u201cCat\u2019s whisker\u201d crystal detector radio manufactured by Japan Radio Co., Ltd.<br>(The photograph depicts a duplicate fabricated by YRP)<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\" id=\"radio-valve\"><span class=\"epb-underline-blue\">\uff15\uff0eDevelopment and History of Vacuum Tubes<\/span><\/h2>\n\n\n\n<p>The vacuum tube makes it possible to transmit and receive radio waves in an efficient and stable manner.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<div class=\"wp-block-media-text alignwide has-media-on-the-right is-stacked-on-mobile\" style=\"grid-template-columns:auto 33%\"><div class=\"wp-block-media-text__content\">\n<p class=\"has-normal-font-size\">A vacuum tube is an electron tube capable of controlling and amplifying electric current. It has a structure consisting of a glass tube with near vacuum condition inside, containing a filament and electrodes. When electric current flows through a filament, a thermionic emission occurs and the electrons move toward an electrode. Taking advantage of this action, electric current can be rectified, amplified, or controlled.<\/p>\n<\/div><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"179\" height=\"300\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/11-179x300-1.jpg\" alt=\"11\" class=\"wp-image-2397 size-medium\"\/><\/figure><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<p>Stripes that do not turn black are formed inside the glass.<\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer is-style-display-pc\"><\/div>\n\n\n\n<p>History of the British Radio Valve to 1940, written by Keith R. Thrower<\/p>\n<\/div>\n<\/div>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"922\" height=\"239\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/21.jpg\" alt=\"\" class=\"wp-image-2402\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/21.jpg 922w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/21-300x78.jpg 300w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/21-768x199.jpg 768w\" sizes=\"auto, (max-width: 922px) 100vw, 922px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">From left to right: Tennis ball type, Eggplant type, ST tubes (two tubes), GT tubes (two tubes), MT tube, and NuVista tube.<\/span><\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"573\" height=\"224\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/22.png\" alt=\"\" class=\"wp-image-2401\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/22.png 573w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/22-300x117.png 300w\" sizes=\"auto, (max-width: 573px) 100vw, 573px\" \/><figcaption class=\"wp-element-caption\"><span data-fontsize=\"16px\" style=\"font-size:16px;\" class=\"epb-font-size\">Various types of vacuum tubes bearing the mark of the former Japanese Navy Insignia<\/span><\/figcaption><\/figure>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<figure class=\"wp-block-image alignright size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/37.png\" alt=\"\"\/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<p>The Yokosuka Naval Arsenal was also engaged in the research and development of vacuum tubes, and manufacturers delivered vacuum tubes bearing the mark of the Naval Insignia.<\/p>\n<\/div>\n<\/div>\n\n\n\n<p>Vacuum tubes evolved significantly in the 1940s, and radio communications with higher frequencies became available. Communications were conducted in high frequency (HF) and medium frequency (MF) at the beginning, but that was expanded to include very high frequency (VHF) and ultra-high frequency (UHF), which is the frequency range available to current mobile phones.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"506\" height=\"259\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/12.jpg\" alt=\"\" class=\"wp-image-2407\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/12.jpg 506w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/12-300x154.jpg 300w\" sizes=\"auto, (max-width: 506px) 100vw, 506px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p>Japan Navy Type 92 Special Receiver Revision 4<\/p>\n\n\n\n<p>A receiver developed for use onboard submarines around 1940s.<\/p>\n\n\n\n<p>The equipment was used on all Navy vessels and land-based stations because of its superior operations and performance.<br>Communications were performed between 20 kHz and 20 MHz.<\/p>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/23.png\" alt=\"\"\/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p>US Army Model PRC-10 FM transceiver<br>A transceiver developed around the 1950s for Army field operations. The equipment was assembled using 16 MT tubes and operated between 38 and 55 MHz.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/24.png\" alt=\"\"\/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"344\" height=\"329\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/25.png\" alt=\"\" class=\"wp-image-2404\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/25.png 344w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/25-300x287.png 300w\" sizes=\"auto, (max-width: 344px) 100vw, 344px\" \/><figcaption class=\"wp-element-caption\">Radio Direction Finder Model KS-321UA<br>manufactured by Koden Electronics Co. Ltd. 1959.<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"447\" height=\"226\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/27.png\" alt=\"\" class=\"wp-image-2403\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/27.png 447w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/27-300x152.png 300w\" sizes=\"auto, (max-width: 447px) 100vw, 447px\" \/><figcaption class=\"wp-element-caption\">High performance radio receiver Model S-20R<br>Double Super-heterodyne Double Conversion Receiver with one high and two mid frequency stages<br>Manufactured in the United States in 1939.<br>manufactured by Hallicrafters<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\" id=\"Wireless-communication-device\">\uff16\uff0e<span class=\"epb-underline-blue\">Evolutionary History of Radio Communication Equipment<\/span><\/h2>\n\n\n\n<p>The evolution of the vacuum tube led to more powerful communications equipment, but people suffered economically from material shortage during the World War II. In order to ensure that people could still listen to radio broadcasts, the Government directed manufacture of radios available at low prices. Radios built with &#8220;Nami&#8221; (meaning &#8220;frugal&#8221; in Japanese) tubes having three or fewer electrodes were popularized as &#8220;Nami San&#8221; (Frugal Model 3) and &#8220;Nami Yon&#8221;(Frugal Model 4) radios.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/28.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Speaker for radio in 1930s<br>(Manufactured by Japan Radio Co., Ltd.)<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"367\" height=\"238\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/29.png\" alt=\"\" class=\"wp-image-2410\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/29.png 367w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/29-300x195.png 300w\" sizes=\"auto, (max-width: 367px) 100vw, 367px\" \/><figcaption class=\"wp-element-caption\">Radio receiver in 1940s<br>referred to as &#8220;Nami Yon&#8221; (Frugal Model 4)<br>&#8220;Televian&#8221; manufactured by Yamanaka Electronics Industries Co., Ltd.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<p>Amateur radio operations that enabled people to communicate freely with people overseas spread explosively after the war. Manufacturers in the United States that were producing communications equipment for military use also started producing receivers for amateur radio operators. Radio equipment made in Japan for amateur operators that offered high performance at low prices and good design was actively exported.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"420\" height=\"227\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/13.jpg\" alt=\"\" class=\"wp-image-2409\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/13.jpg 420w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/13-300x162.jpg 300w\" sizes=\"auto, (max-width: 420px) 100vw, 420px\" \/><figcaption class=\"wp-element-caption\">High performance radio receiver Model 9R-59<br>Double Super-heterodyne (Double Conversion) Receiver with one high and two mid-frequency stages manufactured by Trio in 1959.<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"410\" height=\"184\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/30.png\" alt=\"\" class=\"wp-image-2408\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/30.png 410w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/30-300x135.png 300w\" sizes=\"auto, (max-width: 410px) 100vw, 410px\" \/><figcaption class=\"wp-element-caption\">Radio receiver in 1940s<br>referred to as &#8220;Nami Yon&#8221; (Frugal Model 4)<br>&#8220;Televian&#8221; manufactured by Yamanaka Electronics Industries Co., Ltd.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\"><span class=\"epb-underline-blue\">Advent and Evolution of Semiconductors<\/span><\/h2>\n\n\n\n<p>Transistors were invented in the United States in 1947, and they rapidly replaced vacuum tubes. Transistors became popular because, unlike vacuum tubes, they had no heater, did not operate at high temperatures, and had semi-permanent life. The technology for stacking up many transistors on top of a crystal, the integrated circuits or &#8220;IC&#8221; came about soon after, and electronic equipment became increasingly small. This miniaturization also made it possible to create equipment with signals of even higher frequencies.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"959\" height=\"260\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/08\/31.png\" alt=\"\" class=\"wp-image-2416\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/31.png 959w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/31-300x81.png 300w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/31-768x208.png 768w\" sizes=\"auto, (max-width: 959px) 100vw, 959px\" \/><figcaption class=\"wp-element-caption\">From left to right: \u2460 Germanium diodes, \u2461 Germanium transistors, \u2462 Silicon transistors,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; \u2463 Thick film IC, \u2464 Semiconductor ICs, \u2465 Logic IC, \u2466 LSI (gate array),<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; and \u2467 VLSI (Windows NT \u03bcCPU)<\/figcaption><\/figure>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"334\" height=\"291\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/09\/raadio1.jpg\" alt=\"\" class=\"wp-image-2498\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/raadio1.jpg 334w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/raadio1-300x261.jpg 300w\" sizes=\"auto, (max-width: 334px) 100vw, 334px\" \/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"346\" height=\"288\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/09\/radio2.jpg\" alt=\"\" class=\"wp-image-2499\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/radio2.jpg 346w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/radio2-300x250.jpg 300w\" sizes=\"auto, (max-width: 346px) 100vw, 346px\" \/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"405\" height=\"287\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/09\/radio3.jpg\" alt=\"\" class=\"wp-image-2500\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/radio3.jpg 405w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/radio3-300x213.jpg 300w\" sizes=\"auto, (max-width: 405px) 100vw, 405px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\" id=\"cellphone\">7.  <span class=\"epb-underline-blue\">Advent and History of Mobile Phones<\/span><\/h2>\n\n\n\n<p>The demand for transceivers that made it possible to engage in conversations even while in transit became increasingly high as the world entered a peaceful era and flourished economically. Varieties of transceivers were created, but their biggest shortfall was that they did not link up to a public network.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\">Low power transceiver<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/14-2.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Transceiver for citizens band radio communications Frequency: 27 MHz band<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 8 channels<br>Model RJ-380 manufactured by Matsushita Electric Ind. in 1978<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\">Micro-power transceiver<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/35.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">requiring no license to operate<br>Model GT-02 manufactured by Gakken in 1979<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-top is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\">Amateur radio station<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/08\/36.png\" alt=\"\"\/><figcaption class=\"wp-element-caption\">Band: 144MHz\/435MHz<br>Model TH-77 manufactured by Kenwood<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n<p>Car phones started to circulate in Japan in 1979, and it was in 1987 when the phones became light and small enough for people to carry around on their person. There had been four times of generation changes so far. In order to achieve the third generation, to unify the systems around the world, the YRP was established, wherein the forces from Japan as well as overseas gathered.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"681\" height=\"170\" src=\"http:\/\/194.91.4.36\/en\/wp-content\/uploads\/2022\/09\/cellphone.jpg\" alt=\"\" class=\"wp-image-2491\" srcset=\"https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/cellphone.jpg 681w, https:\/\/yrp.co.jp\/en\/wp-content\/uploads\/2022\/09\/cellphone-300x75.jpg 300w\" sizes=\"auto, (max-width: 681px) 100vw, 681px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\" style=\"font-size:14px\">Tapping was possible using some enhanced radio receivers, since the modulation was analog FM.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\" style=\"font-size:14px\">Tapping was prevented&nbsp; with adopting digital modulation and encryption, but various systems are mixed.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-small-font-size\">The &nbsp;globally unified system as IMT-2000<\/p>\n\n\n\n<p class=\"has-small-font-size\">YRP made contribution,<br>on W-DMA\/CDMA2000<\/p>\n\n\n\n<p class=\"has-text-align-center\" style=\"font-size:14px\"><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"has-text-align-center\" style=\"font-size:14px\">Mobile phones became personal computers in the form of smart phones<\/p>\n<\/div>\n<\/div>\n\n\n\n<p>As a result, the 3rd generation (W-CDMA\/CDMA-2000) service started in 2001. The number of people using the Internet on mobile phones has increased rapidly, and we are now in the age of fourth-generation mobile phones, which have the same heart as PCs (personal computers).<\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\" id=\"link\"><span class=\"epb-underline-blue\">Links<\/span><\/h2>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__initial wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><a class=\"epb-linkcard_link\" href=\"http:\/\/www.museum.yokosuka.kanagawa.jp\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:2px;border-bottom-width:2px;border-left-width:2px;border-right-width:2px;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Yokosuka City Museum<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__initial wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><a class=\"epb-linkcard_link\" href=\"https:\/\/www.kinenkan-mikasa.or.jp\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:2px;border-bottom-width:2px;border-left-width:2px;border-right-width:2px;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Memorial Ship MIKASA<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__initial wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><a class=\"epb-linkcard_link\" href=\"https:\/\/www.mod.go.jp\/gsdf\/sigsch\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:2px;border-bottom-width:2px;border-left-width:2px;border-right-width:2px;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Ground Self-Defense Force Camp Kurihama Communication School History Museum<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__initial wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><a class=\"epb-linkcard_link\" href=\"https:\/\/hct.lab.gvm-jp.groupis-ex.ntt\/index.html\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:2px;border-bottom-width:2px;border-left-width:2px;border-right-width:2px;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">NTT History Center of Technologies<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\" id=\"access\"><span class=\"epb-underline-blue\">Access<\/span><\/h2>\n\n\n\n<p class=\"has-text-align-center\">3-4 Hikarino-oka, Yokosuka-City, Kanagawa-Prefecture, 239-0847, Japan<\/p>\n\n\n\n<div class=\"wp-block-emanon-premium-blocks-button epb-button epb-alignment-center epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" data-button-size=\"m\"><div class=\"epb-btn-size__m\" style=\"--epb-button-text-font-sp:14px;--epb-button-text-font-tablet:14px;--epb-button-text-font-pc:14px;--epb-microcopy-top-font-sp:12px;--epb-microcopy-top-font-tablet:12px;--epb-microcopy-top-font-pc:15px;--epb-microcopy-bottom-font-sp:12px;--epb-microcopy-bottom-font-tablet:12px;--epb-microcopy-bottom-font-pc:12px\"><div class=\"epb-microcopy-top\" data-fontweight=\"normal\">See the location maps<\/div><a style=\"--epb-button-bg-color:#f2f3f3;--epb-button-border-size:1px\" class=\"epb-btn epb-btn__outline is-style-epb-radius__25 is-style-epb-button__standard is-style-epb-hover__initial\" href=\"https:\/\/www.yrp.co.jp\/en\/yrp-outline\/direction\/\"><span class=\"epb-btn-text\" data-fontweight=\"normal\" style=\"line-height:1;letter-spacing:0em\">Access map<\/span><\/a><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Exhibition Room on History of Wireless Communications In order to further deepen the understanding of the hist [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1394,"parent":0,"menu_order":304,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-33","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/pages\/33","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/comments?post=33"}],"version-history":[{"count":6,"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/pages\/33\/revisions"}],"predecessor-version":[{"id":3594,"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/pages\/33\/revisions\/3594"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/yrp.co.jp\/en\/wp-json\/"}],"wp:attachment":[{"href":"https:\/\/yrp.co.jp\/en\/wp-json\/wp\/v2\/media?parent=33"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}