{"id":6644,"date":"2016-01-20T11:52:00","date_gmt":"2016-01-20T00:52:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2016\/01\/20\/another-am-broadcast-interference-story\/"},"modified":"2016-01-20T11:52:00","modified_gmt":"2016-01-20T00:52:00","slug":"another-am-broadcast-interference-story","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2016\/01\/20\/another-am-broadcast-interference-story\/","title":{"rendered":"Another AM Broadcast Interference Story"},"content":{"rendered":"<p><b>Bill,Pete<\/b><br \/> <b><br \/><\/b> <b>Another great solder smoke podcast today. I especially liked the detail <br \/>of you using the S-meter to check on the local broadcast station, and <br \/>the better reception you had on 160 with a resonant antenna. Before I <br \/>retired I had spent over 25 years as a field service tech working on <br \/>neurological instrumentation. One of the test our instruments performed <br \/>was called an Electro-Myography. Part of this test involved a needle <br \/>electrode being inserted into a muscle. This was fed to an <br \/>instrumentation amplifier connected to a computer that processed the <br \/>output of the amplifier. The signal from the amplifier was also fed to <br \/>a speaker so you could also hear the response of the muscle fibers <br \/>activating as you flexed the muscle. One of my customers called and <br \/>said that quite often when he inserted the needle electrode, he heard <br \/>music instead.<br \/>I made a trip to his office and using a field strength meter, I could <br \/>see the modulation peaks on the FSM. But only in one location against <br \/>the wall in the exam room. I at first thought it might be from a <br \/>speaker cable for their intercom \/ background music system in the wall. <br \/>But there was no wires near that location , and it was an outside <br \/>wall. I went outside with the FSM and found that the signal was coming <br \/>from the down-spout for the rain gutter. Apparently the gutter was <br \/>resonant at the frequency of the local AM station and the received <br \/>signal was being radiated through the wall and picked up by the amplifier.<br \/>I quickly got the set of jumper cables out of my van and connected the <br \/>down-spout to a near by water faucet, the signal went away. After a <br \/>quick trip to the local Home-Despot and picking up some heavy copper <br \/>wire and a ground clamp for the water pipe I was able to fix this <br \/>problem. It is amazing how broadcast interference can show up in so <br \/>many places.<\/p>\n<p>DuWayne<br \/><\/b><i><\/i><u><\/u><sub><\/sub><sup><\/sup><strike><\/strike><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Bill,Pete Another great solder smoke podcast today. I especially liked the detail of you using the S-meter to check on the local broadcast station, and the better reception you had on 160 with a resonant antenna. Before I retired I had spent over 25 years as a field service tech working on neurological instrumentation. One &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2016\/01\/20\/another-am-broadcast-interference-story\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Another AM Broadcast Interference Story&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[45],"tags":[],"class_list":["post-6644","post","type-post","status-publish","format-standard","hentry","category-interference"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/6644","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=6644"}],"version-history":[{"count":0,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/6644\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=6644"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=6644"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=6644"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}