Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Loading]

During the hot weather the attenuation increases by 2db, During the day it will be 67db, but at night it is always 66db, I know this because it needs a resync every morning and night. Also during the hot weather We lose 3db n.m on the upstream and about 2db on the downstream. Surely it should stay the same?

[c6em]

No, the overall attenuation figure is measured over how much of the frequency spectrum the ADSL connection actually uses at re-sync......it is an artificial figure.

[konrado5]

I have the same, it implicates you have a fault.

[Loading]

So the higher number of errors and lower noise margin is just the norm of hot weather? So why was it when it was cold during the winter the attenuation went down to 62db Line attenuation?

[konrado5]

I don't know if it is normal if line is provisioned aerially. My line is provisioned underground and I have 0.9-1.6 dB SNR margin every day and night.

[Loading]

Thats the amount mine fluctuates every couple of seconds . Bt need to fix this now it's been on going for a year! Still nothing seems to be found

[konrado5]

How is your line provisioned: underground or aerially?

Best regards
konrado5

[Loading]

Aerially but didn't have this problem before bt messed with something in the exchange.
 

[JGO]

I have the same, it implicates you have a fault.

All metallic conductors have a positive temperature of resistance so loss will increase with temperature. I calculated something  about 1 dB in hot weather for copper, but this requires correction for skin effect over the working frequency range and again if the wires include plated steel, aluminium or W.H.Y.  It does NOT imply a fault condition, so don't loose sleep. 

[konrado5]

I have the same line attenuation during day and during night.

[Loading]

There must be more than one fault on my connection, but its the engineer who will have to find it! Even though the attenuation increases surely it shouldn't have that kind of affect on the n.m should it .

[roseway]

There must be more than one fault on my connection, but its the engineer who will have to find it! Even though the attenuation increases surely it shouldn't have that kind of affect on the n.m should it .

If it doesn't re-sync, then an increase in attenuation will result in an equivalent reduction in SNRM (increased attenuation means a reduced signal, and therefore a reduced signal-to-noise ratio).

[konrado5]

But reduction in SNRM shouldn't be so high.

[Loading]

So you are therefore saying for every 1db of attenuation it costs me 3db?

[roseway]

So you are therefore saying for every 1db of attenuation it costs me 3db?

No, I'm just saying that there's a link. How much the one affects the other depends on how the modem calculates attenuation and SNRM (both are some sort of average over the tone range).