ratchet Posted December 31, 2005 CID Share Posted December 31, 2005 Is there any significan't difference between a Signal to Noise Ratio of 39 dB and 40 dB? Is it even 2.5% or doesn't it even work that way? Quote Link to comment Share on other sites More sharing options...
dn0 Posted December 31, 2005 CID Share Posted December 31, 2005 Actually both numbers are very good readings, and there would be no difference in performance. The minimum downstream SNR for good performance in 256QAM is 32dB. Quote Link to comment Share on other sites More sharing options...
ratchet Posted December 31, 2005 Author CID Share Posted December 31, 2005 Ok, thank you! Next question: several times so far thi month it has been below 0 here in PA and the reading has dropped to 32. The only time it has ever been below 39. What do you think is happening? I'll get home from work and it might only be 15 out, however, the ratio will be back to 39. Quote Link to comment Share on other sites More sharing options...
dn0 Posted December 31, 2005 CID Share Posted December 31, 2005 That is quite a swing from 39-32 even with the cold temps. RF levels actually increase when it is colder out because there is less attenuation when the cables are cold. And the cables are physically shorter when there cold - you may notice power/telephone/cable lines droop down low on a hot day - on a cold day there tight as a piano string. It still should not affect your downloads much even when it drops to 32dB. What is your Rx level? Quote Link to comment Share on other sites More sharing options...
ratchet Posted December 31, 2005 Author CID Share Posted December 31, 2005 What is Rx? I am aware of the better signals in the cold that is why I didn't understand what is going on those couple extra cold mornings. Her are all my values at the moment! Downstream Value Frequency 495000000 Hz Locked Signal to Noise Ratio 39 dB Power Level 7 dBmV The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading Upstream Value Channel ID 3 Frequency 23000000 Hz Ranged Power Level 45 dBmV This of course is Upstream! Status | Signal | Addresses | Configuration | Logs | Help Quote Link to comment Share on other sites More sharing options...
dn0 Posted December 31, 2005 CID Share Posted December 31, 2005 What is Rx? Sorry should have been more clear; I wasn't referring to your current prescription drug level. :haha: I meant the receive level which is the '7 dBmv' reading from your diag page. If the plant or mainline levels are hot on your run, then the colder periods could be putting one or more of the amplifiers over the edge and that will cause distortions in the signals. This may be the case, but not the only possibility. Quote Link to comment Share on other sites More sharing options...
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