{"id":9519,"date":"2013-01-01T16:48:00","date_gmt":"2013-01-01T05:48:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2013\/01\/01\/high-pitched-audio-qrm-in-ss-148\/"},"modified":"2025-07-22T02:40:19","modified_gmt":"2025-07-21T16:40:19","slug":"high-pitched-audio-qrm-in-ss-148","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2013\/01\/01\/high-pitched-audio-qrm-in-ss-148\/","title":{"rendered":"High Pitched Audio QRM in SS #148"},"content":{"rendered":"
<\/a><\/div>\n

Two listeners blessed with good high frequency hearing alerted me to the fact that the latest podcast had some annoying high pitched noise in the background. Peter, VK2TPM was the first to report it — he sent along the above spectral analysis of a gap between words. Steve, W1KF, also heard it, and provided a clue that I think solved the mystery. <\/b>

<\/b> Steve noted that the noise was not present during the sponsor ads that were included in this episode. <\/b>
That let me figure it out. On Saturday when I was recording this, I got through about half the show when the power went out (that happens a lot here). The battery in the laptop I was using to record the podcast saved the day and no data was lost. The power came back on within a few minutes, but the outage had turned off the main PC in the shack. That PC (AND ITS FAN) remained off when I was recording the ads. I did the same kind of noise removal processing that I always do, but this time the noise sample that I used was taken from the mic with the main PC (AND ITS FAN) turned off. My guess is that the whine from the fan (which I can’t hear due to tinnitus) didn’t make it into the noise sample, and thus didn’t get removed from the podcast audio. I went back and did a couple of rounds of noise removal and low pass filtering. I think (I HOPE) I got rid of the offending noise. <\/b>
I have uploaded a new and hopefully improved version of the podcasts. Audio reports will be appreciated. <\/b>

<\/b> One of my New Years resolutions is to improve the technical and substantive quality of the podcast. <\/b>

<\/b> Thanks Peter, Thanks Steve. <\/b>

<\/b> Happy New Year to all! <\/b>
<\/b>
Our book: “SolderSmoke — Global Adventures in Wireless Electronics” http:\/\/soldersmoke.com\/book.htm<\/a> Our coffee mugs, T-Shirts, bumper stickers: http:\/\/www.cafepress.com\/SolderSmoke<\/a> Our Book Store: http:\/\/astore.amazon.com\/contracross-20<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Two listeners blessed with good high frequency hearing alerted me to the fact that the latest podcast had some annoying high pitched noise in the background. Peter, VK2TPM was the first to report it — he sent along the above spectral analysis of a gap between words. Steve, W1KF, also heard it, and provided a … Continue reading “High Pitched Audio QRM in SS #148”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":9520,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[219,49,25],"tags":[],"class_list":["post-9519","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-microphone","category-soldersmoke-podcast","category-troubleshooting"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/9519","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=9519"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/9519\/revisions"}],"predecessor-version":[{"id":9521,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/9519\/revisions\/9521"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/9520"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=9519"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=9519"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=9519"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}