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View Full Version : Power levels - are they OK?

jem16
23-06-2009, 07:42
I had a new modem, Virgin 256, fitted yesterday.

Power levels are;

Downstream Lock : Locked
Downstream Channel Id : 4
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 6.8 dBmV
Downstream SNR : 40.5 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 37500000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 57.0 dBmV
Upstream Mini-Slot Size : 2

I asked the engineer about the high upstream level and was told it was fine as it was under 60dBmV and stable.

Is it ok or should I be asking for another visit?
Peter_
23-06-2009, 07:45
The upstream is on the high side but how is your connection at the moment.
jem16
23-06-2009, 07:57
Since I changed over to my Linksys router the connection has been stable and no apparent problems.

Only issue is speed at the moment as I'm getting around 8/9 mb on a 20mb connection. However from memory it's my old Linksys router which cannot handle anything higher than 10mb. I've had to swap back to that as neither of my Netgear routers (Virgin or my own) will work without the connection dropping out.
ro53ben
23-06-2009, 10:40
Sounds like time for a new router, one without a Netgear badge.
Ignitionnet
23-06-2009, 16:22
Upstream Modulation : QAM16
Upstream transmit Power Level : 57.0 dBmV

This is not acceptable and needs to be fixed. Should be max 55 and ideally 53 or under, it's outside spec.

The engineer was talking out of his bottom a bit, no modem on the network should ever be at 60dBmV the specs mandate a maximum of 58dBmV even if the modem itself can go higher.

For 16QAM maximum specified transmit power is 55dBmV and 53dBmV is where it really should be at most.

QPSK add 3 to both of the above as it uses half the power, so 58 and 53.
jem16
23-06-2009, 17:00
Sounds like time for a new router, one without a Netgear badge.

I intend to buy a new Linksys router.

For 16QAM maximum specified transmit power is 55dBmV and 53dBmV is where it really should be at most.

What issues might it cause being too high?

QPSK add 3 to both of the above as it uses half the power, so 58 and 53.

Don't follow this - what do you mean?

Lastly - how do i get an engineer who will take this seriously and fix the levels and not just tell me that less than 60 is fine?