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Sephiroth · 07-11-2023, 20:52

The power level range for d3.1 is the same as it was for D3.0. That is because at the symbol level, its just a collection binary bits out of which the modem has to make sense.

The official (CableLabs) range is -15dBmv t0 +15dBm. That is the range within which the modem will try and make sense of what it is receiving. The practical range is c. -7dBmv through +15dbMv. Sometimes the higher power level (above 10dBmv) can be problematical if there is considerable noise that gets amplified by that high power.

-2dBmv is fine. D3.1 downstream can operate in a frequency range of 252 MHz to 1788MHz (D3.0 is constrained to 1002MHz at the high end). In practice, VM use a frequency above 690MHz which will attenuate the power transmitted by the last active node (c. 44 dBmv iIrc).

A good technical read at: https://www.commscope.com/globalasse...-docsis-wp.pdf

07-11-2023, 20:52	#65
Sephiroth Wisdom & truth Join Date: Jul 2009 Location: RG41 Services: RG41: 1Gig VOLT Rutland: Gigaclear 400/400 Posts: 12,652	Re: 5th Upstream The power level range for d3.1 is the same as it was for D3.0. That is because at the symbol level, its just a collection binary bits out of which the modem has to make sense. The official (CableLabs) range is -15dBmv t0 +15dBm. That is the range within which the modem will try and make sense of what it is receiving. The practical range is c. -7dBmv through +15dbMv. Sometimes the higher power level (above 10dBmv) can be problematical if there is considerable noise that gets amplified by that high power. -2dBmv is fine. D3.1 downstream can operate in a frequency range of 252 MHz to 1788MHz (D3.0 is constrained to 1002MHz at the high end). In practice, VM use a frequency above 690MHz which will attenuate the power transmitted by the last active node (c. 44 dBmv iIrc). A good technical read at: https://www.commscope.com/globalasse...-docsis-wp.pdf __________________ *Seph.* My advice is at your risk.