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Author Topic: Pilot tone  (Read 334 times)

Weaver

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Pilot tone
« on: November 15, 2020, 09:19:15 AM »

I donít understand the pilot tone in DSL; Is it meant for detecting the presence of the service ?

I read in a Huawei document that the downstream pilot tone is supposed to be tone 64 and thereís supposed to be an upstream tone at tone 16. I am seeing a drop down to bit loading=2 on tone 69, not tone 64, and Iím not seeing any bit loading drop on tone 16 so I donít understand where that has disappeared to.
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licquorice

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Re: Pilot tone
« Reply #1 on: November 15, 2020, 04:41:02 PM »

At the risk of teaching grandma to suck eggs, the purpose of a pilot tone is to give a standard reference frequency for setting/measuring signal levels.
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Weaver

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Re: Pilot tone
« Reply #2 on: November 15, 2020, 07:22:38 PM »

Thank you. Iím not qualified as a grandma. Do you know why Iím not seeing the upstream one ? Or why the downstream carries 2 bits?
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licquorice

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Re: Pilot tone
« Reply #3 on: November 15, 2020, 07:56:22 PM »

I'm afraid I have no answer to that. I was just speaking in generic terms as to the purpose of pilot tones in systems.
« Last Edit: November 15, 2020, 07:59:31 PM by licquorice »
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