{"id":24,"date":"2014-05-15T09:24:37","date_gmt":"2014-05-15T09:24:37","guid":{"rendered":"http:\/\/jack32.no-ip.com\/wp\/?p=24"},"modified":"2014-06-24T19:02:35","modified_gmt":"2014-06-24T19:02:35","slug":"messuring-the-frequency-of-androids-nfc","status":"publish","type":"post","link":"http:\/\/theelectronicegg.com\/?p=24","title":{"rendered":"Measuring the frequency of Androids NFC"},"content":{"rendered":"<p>Hey there,<\/p>\n<p>Every blog has to start somewhere&#8230; I have some plans for projects I would like to put here. But a fews days ago I had an idea for a quick thing that should get me started.<\/p>\n<p>I was wondering at what frequency Andrioids NFC is operating at. Sure I COULD ask the mighty Internet&#8230; but thats no fun. Lets measure it! Also I was wondering &#8216;Does NFC turn off when the phone goes into standby?&#8217;.<\/p>\n<p>So I set up my analog Oscilloscope. Formed a simple antenna with my probe. Turned on NFC on my phone and placed it on top.<\/p>\n<p><!-- index.php -->\n<div\n\tclass=\"ngg-galleryoverview ngg-ajax-pagination-none\"\n\tid=\"ngg-gallery-83-1\">\n\n    \t<div class=\"slideshowlink\">\n        <a href='http:\/\/theelectronicegg.com\/index.php\/nggallery\/slideshow?p=24'>[Show slideshow]<\/a>\n\t\t\n\t<\/div>\n\t\t\t<!-- Thumbnails -->\n\t\t\t\t<div id=\"ngg-image-0\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14926.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14926.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14926.jpg\"\n               data-image-id=\"6\"\n               data-title=\"SDC14926\"\n               data-description=\"\"\n               data-image-slug=\"sdc14926\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14926\"\n                    alt=\"SDC14926\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14926.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\t\t<div id=\"ngg-image-1\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14925.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14925.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14925.jpg\"\n               data-image-id=\"5\"\n               data-title=\"SDC14925\"\n               data-description=\"\"\n               data-image-slug=\"sdc14925\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14925\"\n                    alt=\"SDC14925\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14925.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\t\t<div id=\"ngg-image-2\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14916.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14916.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14916.jpg\"\n               data-image-id=\"4\"\n               data-title=\"SDC14916\"\n               data-description=\"\"\n               data-image-slug=\"sdc14916\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14916\"\n                    alt=\"SDC14916\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14916.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\t\t<div id=\"ngg-image-3\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14953.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14953.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14953.jpg\"\n               data-image-id=\"8\"\n               data-title=\"SDC14953\"\n               data-description=\"\"\n               data-image-slug=\"sdc14953\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14953\"\n                    alt=\"SDC14953\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14953.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\t\t<div id=\"ngg-image-4\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14953_2.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14953_2.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14953_2.jpg\"\n               data-image-id=\"9\"\n               data-title=\"SDC14953_2\"\n               data-description=\"\"\n               data-image-slug=\"sdc14953_2\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14953_2\"\n                    alt=\"SDC14953_2\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14953_2.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\t\t<div id=\"ngg-image-5\" class=\"ngg-gallery-thumbnail-box\" >\n\t\t\t\t        <div class=\"ngg-gallery-thumbnail\">\n            <a href=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14932.jpg\"\n               title=\"\"\n               data-src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/SDC14932.jpg\"\n               data-thumbnail=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14932.jpg\"\n               data-image-id=\"7\"\n               data-title=\"SDC14932\"\n               data-description=\"\"\n               data-image-slug=\"sdc14932\"\n               class=\"ngg-fancybox\" rel=\"83\">\n                <img\n                    title=\"SDC14932\"\n                    alt=\"SDC14932\"\n                    src=\"http:\/\/theelectronicegg.com\/wp-content\/gallery\/nfc\/thumbs\/thumbs_SDC14932.jpg\"\n                    width=\"120\"\n                    height=\"90\"\n                    style=\"max-width:100%;\"\n                \/>\n            <\/a>\n        <\/div>\n\t\t\t\t\t\t\t<\/div> \n\t\t\t\n        \n\t\t\n\t\t<!-- Pagination -->\n\t<div class='ngg-clear'><\/div>\t<\/div>\n<\/p>\n<p>Easy! The scope shows a nice sine wave. Timebase is set to 20 ns per devision. And I get about 8.6 devisions per wavelength. That calculates to a frequency of about 14.5 Mhz (OK. Yes, I checked online. The &#8220;right&#8221; answer is 13.56 MHz). The signal disappears when I turn off the display and reappears when I unlock the phone. So I guess if you buy some of these cheap NFC tags, you need to unlock the phone and then put it on top. So i might as well turn on my bluetooth by hand rather than unlocking my screen and then put it on that NFC tag that I don&#8217;t have in my car.<\/p>\n<p>The signal comes in bursts of about 5.4 ms every 265 ms. Which is not so easy to capture and measure with my analog scope. But I took some photos and made it work. The length of the burst is hard to see. So I edited the picture to make it appear more clearly. The last picture shows my attempt to measure the dead period between to bursts.<\/p>\n<p>Thats it! Leave your comments below.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Hey there, Every blog has to start somewhere&#8230; I have some plans for projects I would like to put here. But a fews days ago I had an idea for a quick thing that should get me started. I was wondering at what frequency Andrioids NFC is operating at. Sure I COULD ask the mighty [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[11],"tags":[13,12,14,16],"_links":{"self":[{"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/posts\/24"}],"collection":[{"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=24"}],"version-history":[{"count":7,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/posts\/24\/revisions"}],"predecessor-version":[{"id":86,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=\/wp\/v2\/posts\/24\/revisions\/86"}],"wp:attachment":[{"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=24"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=24"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/theelectronicegg.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=24"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}