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Doppler effect at 27 MHz? How fast do you drive anyway? :shock: Max doppler shift at 10m travelling at 60 MPh (100 KMh) is only 2.44 Hertz or twice that for both vehicles traveling towards each other. 5 hertz will not be a factor.

Doppler shift versus freq at 100 KMh

Doppler shift on a LEO sat is only +/- 3 KHz at 144 MHz and a few thousand miles per hour.

I use SSB all the time even on 50 MHz with out a problem. I have used it a few times on 144 MHz as well and the only problem there has been the picketing effect of being in motion but not doppler shift.

<blockquote data-quote="Captain Kilowatt" data-source="post: 83350" data-attributes="member: 39">Doppler effect at 27 MHz? How fast do you drive anyway?&nbsp; :shock:&nbsp;&nbsp; <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f606.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":lol:" title="Laugh&nbsp; &nbsp; :lol:"&nbsp; data-smilie="19"data-shortname=":lol:" /> Max doppler shift at 10m travelling at 60 MPh (100 KMh) is only 2.44 Hertz or twice that for both vehicles traveling towards each other. 5 hertz will not be a factor. <a href="http://www.qsl.net/vk3jed/doppler.html" target="_blank">Doppler shift versus freq at 100 KMh</a>Doppler shift on a LEO sat is only +/- 3 KHz at 144 MHz and a few thousand miles per hour.I use SSB all the time even on 50 MHz with out a problem. I have used it a few times on 144 MHz as well and the only problem there has been the picketing effect of being in motion but not doppler shift.</blockquote>

[QUOTE="Captain Kilowatt, post: 83350, member: 39"] Doppler effect at 27 MHz? How fast do you drive anyway? :shock: :lol: Max doppler shift at 10m travelling at 60 MPh (100 KMh) is only 2.44 Hertz or twice that for both vehicles traveling towards each other. 5 hertz will not be a factor. [url=http://www.qsl.net/vk3jed/doppler.html]Doppler shift versus freq at 100 KMh[/url] Doppler shift on a LEO sat is only +/- 3 KHz at 144 MHz and a few thousand miles per hour. I use SSB all the time even on 50 MHz with out a problem. I have used it a few times on 144 MHz as well and the only problem there has been the picketing effect of being in motion but not doppler shift. [/QUOTE]

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