{"id":2760,"date":"2024-01-29T01:13:40","date_gmt":"2024-01-29T01:13:40","guid":{"rendered":"https:\/\/simulide.com\/p\/?p=2760"},"modified":"2024-02-12T04:03:06","modified_gmt":"2024-02-12T04:03:06","slug":"am-modulation-df340","status":"publish","type":"post","link":"https:\/\/simulide.com\/p\/am-modulation-df340\/","title":{"rendered":"AM MODULATION (DF340)"},"content":{"rendered":"<h2><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/02\/AM_MODULATIONa.png\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-full  aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/02\/AM_MODULATIONa.png\" alt=\"\" width=\"602\" height=\"362\" \/><\/a><\/h2>\n<h2><strong><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">(Simulide R2116 or higher.) DF340A.<\/span><\/span> <\/span><\/strong><\/h2>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">Modulation in<strong> AM<\/strong> is obtained by <em><strong>modifying the power<\/strong><\/em> of the modulating stage so that the <strong>positive and negative<\/strong> half-waves of the carrier wave are modulated with a phase shift of <strong>180 degrees<\/strong> with the same modulating signal, otherwise what is called <strong>overmodulation<\/strong> occurs.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">which leaves the carrier at a constant amplitude and therefore the emission of the signal does not occur.<\/span><\/span> <\/span><\/p>\n<p><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/AM.png\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-full  aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/AM.png\" alt=\"\" width=\"127\" height=\"144\" \/><\/a><\/p>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The <strong>AM broadcast<\/strong> of commercial radio stations, amateur radio stations and others has been replaced by <strong><em>FM broadcasting<\/em><\/strong>, which has advantages in terms of broadcast <strong>quality<\/strong> due to its lower sensitivity to disturbances.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">However, <strong>AM<\/strong> is still used due to the simplicity of the system in general, both in <em><strong>emission and reception<\/strong><\/em>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The commercial AM band is between <em><strong>500 kHz and 1700 kHz<\/strong><\/em>.<\/span><\/span> <\/span><\/p>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">In <strong>this porject<\/strong> we use a much lower carrier frequency, <strong>10kHz<\/strong> because what we intend is simply to do a practical simulation of this type of modulation.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The modulator signal must be noticeably lower than that of the carrier, in our case<strong> 40 Hz<\/strong> as a base.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">At the output of the diagram on the<strong> oscilloscope<\/strong>, the <em><strong>modulating signa<\/strong><\/em>l and the already <em><strong>modulated carrier<\/strong><\/em> are shown.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">To manage this modulator we have three controls:<\/span><\/span> <\/span><\/p>\n<ul>\n<li><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>a) Modulator wave<\/strong> type switch.<\/span><\/span><\/span><\/li>\n<li><span class=\"HwtZe\" lang=\"en\"> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>b) A potentiometer<\/strong> to control the <strong>level<\/strong> of the modulating signal.<\/span><\/span><\/span><\/li>\n<li><span class=\"HwtZe\" lang=\"en\"> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>c) A potentiometer<\/strong> to control <strong>modulation depth<\/strong><\/span><\/span><\/span><\/li>\n<\/ul>\n<p><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/FUERA.png\"><img decoding=\"async\" class=\"attachment-full size-full aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/FUERA.png\" alt=\"\" \/><\/a><\/p>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">To know more about AM modulation:\u00a0<\/span><\/span><\/span> <a href=\"https:\/\/en.wikipedia.org\/wiki\/Amplitude_modulation\">https:\/\/en.wikipedia.org\/wiki\/Amplitude_modulation<\/a><\/p>\n<p><strong><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">SCHEME:<\/span><\/span><\/span><\/strong><\/p>\n<div class=\"lRu31\" dir=\"ltr\"><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The circuit in our example is composed of <strong>three operational amplifiers<\/strong> that do all the operation with a symmetrical 5V supply <strong><em>(+5V and -5V)<\/em><\/strong>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The output opamp directly receives the <strong>10kHz carrier wave<\/strong> and the <strong>40 Hz modulating signal<\/strong> is introduced into its <strong>positive<\/strong> and <em><strong>negative power inputs<\/strong><\/em>. At the positive power input its opamp is amplification with a phase shift of <strong>ZERO degrees<\/strong> and in the power supply<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">negative with a phase shift of <strong>180 degrees<\/strong>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The input of these opamps is common and is controlled by <strong>two potentiometers<\/strong>: One to adjust the signal input <strong>LEVEL<\/strong> and another to adjust the carrier modulation <strong>DEPTH<\/strong>, 50% is a standard setting.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">At the input of the level potentiometer, a <strong>switch<\/strong> has been provided to select the <em><strong>type of wave to be emitted<\/strong><\/em>: Sinusoidal, sawtooth, triangular, square, random and an input of a variable oscillator.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The output of the <strong>modulator<\/strong> stage and that of the<strong> zero phase<\/strong> shift opamp have been applied to the oscilloscope.<\/span><\/span><\/span><\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div dir=\"ltr\">\n<h2 class=\"lRu31\"><span class=\"HwtZe\" lang=\"en\"><strong><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">AM-MODULATOR AND SIMPLE DEMODUL.<\/span><\/span> <\/strong><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>(Simulide, R2094 or higher). DF340B<\/strong><br \/><\/span><\/span><\/span><\/h2>\n<\/p>\n<\/div>\n<div dir=\"ltr\"><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/AM_MODULATION__DEMOD.png\"><img decoding=\"async\" class=\"attachment-full size-full aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/AM_MODULATION__DEMOD.png\" alt=\"\" \/><\/a><\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div dir=\"ltr\">\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">This Project is an AM <strong><em>modulator<\/em><\/strong> and a <em><strong>simple demodulator<\/strong><\/em>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The modulator is a subcircuit with the diagram of example 340. The carrier wave is a <strong>30 kHz<\/strong> sine wave (Changeable by clicking on the modulator).<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The modulating wave is <strong>40 Hz.<\/strong><\/span><\/span><\/span><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The <strong>demodulator<\/strong> is composed of a <strong><em>rectifier diode<\/em><\/strong> to eliminate the negative half-wave and an <strong><em>LC filter<\/em><\/strong> to eliminate carrier remains.<\/span><\/span><\/span><\/div>\n<div>\u00a0<\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The <strong>modulator oscilloscope<\/strong> shows the modulated and modulating wave.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">On <strong>demodulator oscilloscope<\/strong> shows the modulating wave extracted from the AM.<\/span><\/span><\/span><\/div>\n<div>\u00a0<\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>MODULATOR CONTROLS<\/strong>:<\/span><\/span><\/span><\/div>\n<div>\u00a0<\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">a) <strong>Waveform selector<\/strong> with EXT position to connect another oscillator (Pressing several positions simultaneously shows curious modulations).<\/span><\/span><\/span><\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">b) The potentiometer next to EXT adjusts its input level.<\/span><\/span><\/span><\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">c) <strong>WAVE:<\/strong> Adjust the level of the modulating signal.<\/span><\/span><\/span><\/div>\n<div><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">d) <strong>DPTH<\/strong>: Adjust the modulation depth.<\/span><\/span><\/span><\/div>\n<\/div>\n<div>\u00a0<\/div>\n<div>\n<div class=\"lRu31\" dir=\"ltr\"><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b Jj6Lae\"><span class=\"ryNqvb\">Examples of modulations achieved with <strong>the modulator subcircuit<\/strong>:<\/span><\/span><\/span><\/p>\n<div id=\"ow3265\">\u00a0<\/div>\n<\/div>\n<\/div>\n<div dir=\"ltr\"><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/ONDAS.png\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-full  aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/ONDAS.png\" alt=\"\" width=\"786\" height=\"257\" \/><\/a><\/div>\n<div dir=\"ltr\">\n<h3><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The modulator subcircuit contains the same structure of the modulator already discussed.<\/span><\/span><\/span><\/h3>\n<h2><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/SUBCIRCUIT-1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-full  aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/SUBCIRCUIT-1.png\" alt=\"\" width=\"312\" height=\"307\" \/><\/a><\/h2>\n<h2 class=\"lRu31\"><span class=\"HwtZe\" lang=\"en\"><strong><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">OVERMODULATION.<\/span><\/span> <\/strong><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>(Simulide, TRUNK R2094 or higher). DF340C.<\/strong><\/span><\/span><\/span><\/h2>\n<\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div dir=\"ltr\"><a href=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/OVERMODULATION.png\"><img loading=\"lazy\" decoding=\"async\" class=\"attachment-full  aligncenter\" src=\"https:\/\/simulide.com\/p\/storage\/2024\/01\/OVERMODULATION.png\" alt=\"\" width=\"703\" height=\"472\" \/><\/a><\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div dir=\"ltr\"><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">This scheme corresponds to a circuit that <strong>adds<\/strong> the <strong>carrier<\/strong> plus the <strong>modulating signal<\/strong>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">Here in the positive and negative half waves the modulating wave is <strong>in phase<\/strong>, this is called <strong>OVERMODULATION<\/strong> where it can be seen that the carrier always maintains the <strong>same amplitude<\/strong>.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">In this case, there is <em><strong>no amplitude modulation<\/strong><\/em>, so the signal could not be broadcast.<\/span><\/span><\/span><\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div dir=\"ltr\">\n<h3><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>MISCELLANY:<\/strong> <\/span><\/span><\/span><\/h3>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">The attached zip file typically includes: <\/span><\/span><\/span><\/p>\n<p><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>1)<\/strong> Electrical diagram.<br \/><\/span><\/span><\/span><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\"><strong>2)<\/strong> <strong>\u201cdata\u201d<\/strong> folder. <\/span><\/span><\/span><\/p>\n<\/div>\n<h3><strong><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">SUBCIRCUITS:<\/span><\/span> <\/span><\/strong><\/h3>\n<div dir=\"ltr\">\u00a0<\/div>\n<div class=\"lRu31\" dir=\"ltr\"><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">This example <strong>integrates<\/strong> several subcircuits located in the <strong>&#8220;data&#8221; folder<\/strong> into the ZIP attached.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">This folder must always be next to the <strong>&#8220;sim1&#8221; scheme<\/strong> so that it can be executed.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">A <strong>subcircuit<\/strong> is a <strong>&#8220;custom&#8221;<\/strong> circuit that accumulates a set of Simulide <strong>base components (primitive function)<\/strong> to obtain a new or an adapted function.<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">These subcircuits are treated<\/span><\/span> <span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">by Simulide as another component of its own structure. User can <strong>create<\/strong> his own subcircuits or <strong>use<\/strong> the ones published here in your own designs once the procedure is known, explained in detail in the Simulide tutorials:\u00a0 <strong><a href=\"https:\/\/simulide.com\/p\/subcircuits\/\">https:\/\/simulide.com\/p\/subcircuits\/<\/a><\/strong><\/span><\/span><\/span><\/div>\n<div dir=\"ltr\">\u00a0<\/div>\n<div class=\"lRu31\" dir=\"ltr\"><span class=\"HwtZe\" lang=\"en\"><span class=\"jCAhz ChMk0b\"><span class=\"ryNqvb\">* <strong>Communication with the author<\/strong>: Simulide\/User\/Messages\/Defran<\/span><\/span><\/span><\/div>\n\n<style>.wp-block-kadence-spacer.kt-block-spacer-2760_c0b7f7-f1 .kt-block-spacer{height:60px;}.wp-block-kadence-spacer.kt-block-spacer-2760_c0b7f7-f1 .kt-divider{border-top-width:1px;height:1px;border-top-color:#eee;width:80%;border-top-style:solid;}<\/style>\n<div class=\"wp-block-kadence-spacer aligncenter kt-block-spacer-2760_c0b7f7-f1\"><div class=\"kt-block-spacer kt-block-spacer-halign-center\"><hr class=\"kt-divider\"\/><\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Downloads:<\/strong><\/h2>\n\n\n\n<div class=\"wp-block-file\"><a id=\"wp-block-file--media-b8b86c07-9b3d-4954-9330-fc7d922eeb03\" href=\"https:\/\/simulide.com\/p\/wp-content\/uploads\/2024\/01\/AM_MODULATION_DF340.zip\">AM_MODULATION_DF340<\/a><a href=\"https:\/\/simulide.com\/p\/wp-content\/uploads\/2024\/01\/AM_MODULATION_DF340.zip\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-b8b86c07-9b3d-4954-9330-fc7d922eeb03\">Download<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>AM modulation, AM modulation subcircuit and Demodulation, Overmodulation<\/p>\n","protected":false},"author":3,"featured_media":2762,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"footnotes":""},"categories":[10,5],"tags":[],"class_list":["post-2760","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-analog","category-pure-hardware"],"_links":{"self":[{"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/posts\/2760","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/comments?post=2760"}],"version-history":[{"count":24,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/posts\/2760\/revisions"}],"predecessor-version":[{"id":2908,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/posts\/2760\/revisions\/2908"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/media\/2762"}],"wp:attachment":[{"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/media?parent=2760"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/categories?post=2760"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/simulide.com\/p\/wp-json\/wp\/v2\/tags?post=2760"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}