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Re: snap shot of modem

upstream SNR of 25 dB is not good.   the minimum upstream SNR varies depending on what modulation type you are using on your upstream carriers.
25dB will work fine on QPSK modulation, but once you get into the QAM 16, 32, 64 you are going to have problems.   You can't fix upstream SNR by padding an install.   that has to be fixed on the plant level.   As you increase the loss in the install, the modem transmit level will increase correspondingly, but that won't help create more separation between the upstream noise floor, and your modem's peak carrier strength.

You have problems in your mainline plant if you are receiving 34 MER downstream with +10dBmv signal strength.  I would be interested to see what your downstream MER is at 0 dBmv, and that means measuring a zero with no compensation on your meter.   That will give you a better idea of downstream plant performance.   This is all assuming that your install is bulletproofed.  

Your upstream alignment back to the CMTS (ultimately) is off as well if you are only acheiving 25dB upstream SNR at any signal strength.   Like i said, if your upstream modulation is QPSK, you should work, but any higher order modulation scheme will have a hard time getting no errors on the upstream link.
This is CABL.com posting #335577. Tiny Link: cabl.co/mbzsH
Posted in reply to: Re: snap shot of modem by cabledawg71874
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