https://en.wikipedia.org/wiki/S_meter
https://owenduffy.net/index.htm
https://owenduffy.net/rx/SMeter/index.htm
http://www.iz2zqg.radio/en/thoughts-regarding-the-s-meter
https://vu2nsb.com/radio-systems/amateur-radio-station-ham-shack/radio-transceiver-s-meter/
https://www.giangrandi.org/electronics/radio/smeter.shtml
https://sites.google.com/view/vk1hw/others/s-meter-tracking?pli=1
https://www.google.com/search?q=-67dbm+s9+s+meter&newwindow=1&sxsrf=ALiCzsZAIPlqwol_JRFoSQKjbQEtQnsyTA%3A1670510713418&ei=efiRY4r7GNvd5OUPlM6xwA4&ved=0ahUKEwjKm6qtoer7AhXbLrkGHRRnDOgQ4dUDCA8&uact=5&oq=-67dbm+s9+s+meter&gs_lcp=Cgxnd3Mtd2l6LXNlcnAQA0oECEEYAUoECEYYAFC6CFikGGC2ImgBcAB4AIABdIgBgQaSAQMwLjeYAQCgAQHAAQE&sclient=gws-wiz-serp
https://www.google.com/imgres?imgurl=https%3A%2F%2Fowenduffy.net%2Frx%2FSMeter%2FFig01.png&imgrefurl=https%3A%2F%2Fowenduffy.net%2Frx%2FSMeter%2Findex.htm&tbnid=Laa74DSObIzPRM&vet=12ahUKEwi67qe3s-r7AhVLGLkGHYCBDLwQxiAoCXoECAAQJw..i&docid=9vOq3X6gERQymM&w=616&h=642&itg=1&q=-67dbm%20s9%20s%20meter&ved=2ahUKEwi67qe3s-r7AhVLGLkGHYCBDLwQxiAoCXoECAAQJw#imgrc=Hj1YtP1kWnTgmM&imgdii=agsA86ML0I8YfM
https://www.google.com/imgres?imgurl=https%3A%2F%2Fhamsci.org%2Fsites%2Fdefault%2Ffiles%2Fpages%2Fs_meter_calibration%2Fs_meter-fig1.png&imgrefurl=https%3A%2F%2Fhamsci.org%2Fs-meter-calibration&tbnid=uJ07yiGicNrTLM&vet=12ahUKEwiHqrekour7AhXkBbkGHUp4AI8QMygAegUIARCQAQ..i&docid=zzzaB_o-EbD_tM&w=809&h=400&q=-67dbm%20s9%20s%20meter&ved=2ahUKEwiHqrekour7AhXkBbkGHUp4AI8QMygAegUIARCQAQ
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