what do negative SNR values mean?

  • Thread starter Thread starter GeX
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GeX

GeX

Soldato
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Howdy.

Further to my thread re DGTeam firmware, I've kept an eye on my stats when the router was power cycled (power cut kinda forced it!)

Anyway when it came back on, these are the stats;

Code:
ADSL Link	        Downstream	Upstream
Connection Speed	21456 kbps	1020 kbps
Line Attenuation	27.0 db  	15.2 db
Noise Margin	        -5.-5 db	11.6 db

but it wouldn't connect, i just the LCP is allowed to come up error.

So i rebooted it, and got;

Code:
ADSL Link	        Downstream	Upstream
Connection Speed	19340 kbps	1020 kbps
Line Attenuation	26.5 db  	15.2 db
Noise Margin	        -5.-9 db	10.8 db

still same LCP error though.

Rebooted again and got;

Code:
ADSL Link	        Downstream	Upstream
Connection Speed	18579 kbps	1020 kbps
Line Attenuation	26.5 db  	15.2 db
Noise Margin	        9.9 db	        10.3 db

which is my usual sync speed, and it connected fine.

Is the SNR going to - because it drops below 6, and that's not allowed on the stock firmware. With DGTeam I could set it to 5.5 and sync higher?
 
Below 6 is allowed perfectly well. It's probably negative because it's not connected and reporting garbage.
 
I've seen other routers do something similar when their snr drops fairly low, one of my old ones used to report some garbage like -273456. As you have a 10db margin at 18.5mb I can't see it being below 6db at 19.3 so not sure why it would do that.
 
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