Dream Unlocker
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What Should The Power Levels Be ?
Typical values for each (this should not be confused with the levels the ntl: technicians can see from their end, as they use a different measurement system) are:
Note the Downstream power levels are determined by a QAM setting on the network. Increasingly this is 256QAM on ntl: nd Telewest, and can be determined when obtaining these power level readings.
Downstream Power (64QAM - being phased out)
+5 to -15 dBmV with the ideal being close to 0. Values outside of this range would normally result in either an inability to lock onto the network signal, or frequent disconnections.
Downstream Power (256QAM)
+15 to -6 dBmV range, but optimal is +10dBmv to 0 dBmv, with the ideal being close to 5. Values outside of this range would normally result in either an inability to lock onto the network signal, or frequent disconnections.
Upstream Power
Anywhere from 35db to 58 on a Surfboard, 61 on an ntl: 100. Generally lower values are better. If you constantly see 58 on Surfboard or 60/61 on Ambit/ntl: modem this would indicate a poor upstream path and probably result in frequent disconnections.
Signal-to-Noise Ratio (SNR)
For 64QAM downstream, a figure above 25 is desirable, above 30 is ideal.
For 256QAM downstream a figure above 30 is desirable, above 33 is ideal
A low SNR is usually the cause of very slow browsing and high packet loss.
What to look for :
QAM setting (64 or 256)
Downstream power level
Upsream power level
SNR (Signal-to-Noise Ratio)
Typical values for each (this should not be confused with the levels the ntl: technicians can see from their end, as they use a different measurement system) are:
Note the Downstream power levels are determined by a QAM setting on the network. Increasingly this is 256QAM on ntl: nd Telewest, and can be determined when obtaining these power level readings.
Downstream Power (64QAM - being phased out)
+5 to -15 dBmV with the ideal being close to 0. Values outside of this range would normally result in either an inability to lock onto the network signal, or frequent disconnections.
Downstream Power (256QAM)
+15 to -6 dBmV range, but optimal is +10dBmv to 0 dBmv, with the ideal being close to 5. Values outside of this range would normally result in either an inability to lock onto the network signal, or frequent disconnections.
Upstream Power
Anywhere from 35db to 58 on a Surfboard, 61 on an ntl: 100. Generally lower values are better. If you constantly see 58 on Surfboard or 60/61 on Ambit/ntl: modem this would indicate a poor upstream path and probably result in frequent disconnections.
Signal-to-Noise Ratio (SNR)
For 64QAM downstream, a figure above 25 is desirable, above 30 is ideal.
For 256QAM downstream a figure above 30 is desirable, above 33 is ideal
A low SNR is usually the cause of very slow browsing and high packet loss.
What to look for :
QAM setting (64 or 256)
Downstream power level
Upsream power level
SNR (Signal-to-Noise Ratio)
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