Superhub 2 Power levels
 

After getting my hub changed from SH1, I believe my power levels to be a little low?

Power Level (dBmV) -2.88 -3.51 -3.05 -3.66 -3.90 -4.14 -4.16 -4.40
RxMER (dB) 32.87 32.87 32.77 32.58 32.07 31.84 31.84 31.62

I am right that the parameters are between -3 and +7 ? (Old Telewest)

The technician did change something at the cab, power levels for SH1 were always around +1. I am being told that there is no problem with power levels can anyone confirm?

Re: Superhub 2 Power levels
 

Technically, your power levels are just about OK.

It's the SNR that's worrying, 31-32 is way below optimal.

Re: Superhub 2 Power levels
 

Thanks for the quick reply, then why did the tech support not pick up on this?

---------- Post added at 17:52 ---------- Previous post was at 17:34 ----------

Virgin has just told me that there is no problem with my power levels or SNR? He said that they have a traffic light system which shows my SNR and power levels all in the green...

Re: Superhub 2 Power levels
 

Seph's power level & SNR primer recommends 33 dB as a minimum:

Re: Superhub 2 Power levels
 

Is it working?

Yes: Leave it alone
No: Contact tech support

Re: Superhub 2 Power levels
 

Define "working"?

Re: Superhub 2 Power levels
 

no downtime/uninterrupted service and the op can achieve headline speed

Re: Superhub 2 Power levels
 

and is this possible with downstream SNR around 31/32 dB? Maybe the OP can say whether he getting no downtime/uninterrupted service and can achieve headline speeds? If yes then no worries ..

Re: Superhub 2 Power levels
 

The all important thing is the SNR. The OP's SNR is unacceptable and will be czusing corrupted data.

The SH1 would have been reporting around 2 dB higher SNR. If that was giving trouble and a SH2 was fitted, you can see that the problem lies towards the VM end outside the modem. Anything from loosely screwed in cables at the home to a noisy amplifier, noise in the network, breakdown in the wall box splitter etc.

Re: Superhub 2 Power levels
 

Just got off the phone after speaking to a senior technician at VM, again I was assured there were no issues with noise on my line. He told me that SNR would only become a concern on my part of the network at around 20dB.

Power Level (dBmV)-2.41 -3.13 -2.47 -3.07 -3.37 -3.59 -3.58 -3.83
RxMER (dB)33.72 33.60 33.72 33.49 32.87 32.77 32.77 32.50

Re: Superhub 2 Power levels
 

Lol. With a SNR of 20dB there wouldn't be a network to connect to

Re: Superhub 2 Power levels
 

The new signal spec virgin go by is -6 to +8. Snr is a minimum of 34, upstream maximum of 51.

Re: Superhub 2 Power levels
 

I have no down time on my network, and can archive full speeds outside of congested times. Latency doubles or worse at peak times of the day which stops me wanting to game, I just want the best possible experience I can achieve.

I have had a contract with cable for 14 years and have just recently renewed, but with BT fibre coming to my area soon this could be the last year.

Power Level (dBmV) -0.96 -1.72 -0.96 -1.58 -1.92 -2.07 -2.13 -2.38
RxMER (dB) 36.61 36.61 36.61 36.17 35.97 35.60 35.60 35.42

Here are my latest readings, seem to improved a little later in the day. Do not know if this is due to temperature or utilization? If it is temperature then I expect these figures to degrade throughout the upcoming summer.

Re: Superhub 2 Power levels
 

The ST should have known better. 20 dB is likely to be the minimum acceptable noise value of the UPSTREAM at the CMTS (Though AFAIK that should be 22 dB according to the DOCSIS 3 spec.).

---------- Post added at 23:45 ---------- Previous post was at 23:42 ----------

As temperature rises, coax expands and offers higher resistance (at its simplest). So downstream power would fall. SNR is not significantly affected by temperature.

So I reckon they've fixed it or a transient went away.

Re: Superhub 2 Power levels
 

The senior technician from virgin that I spoken to did seem to know his onions, even as far as to know what make of router I had behind my SH2? Thanks for all your input people.

Re: Superhub 2 Power levels
 

That's not a terribly difficult thing to find out. They can see the MAC address of connected devices and there are sites that you can insert that into which will give you the manufacturer.

Re: Superhub 2 Power levels
 

Indeed, and often systems that display it will do an automatic lookup.

That said if he went out of his way to look that up it sounds to me like the opposite, a show off pretending to sound smart by looking up something entirely irrelevant and un-useful...

Re: Superhub 2 Power levels
 

We used to look them up all the time. It was useful to know what was plugged into the modem as many people didn't know if they had a router or not. Or quite a common one was them saying their DELL laptop wasn't working but there'd be a HP MAC (for example) registered with the modem. Reboot and fixed.

Re: Superhub 2 Power levels
 

Yes but in this case it didn't really have any bearing or relevance to the query at all.

I could have similarly looked up every caller's address, their parents' name, or what qualifications they left school with when someone called in but I don't do it just for fun when they have a problem with a printer...

Re: Superhub 2 Power levels
 

I don't know, I don't think you can claim it isn't relevant at that point. For all the tech new, the problem was with the router. Why rule something out before you're done investigating?

I'd much rather the tech was investigating thoroughly than ignoring potentially useful information.

Re: Superhub 2 Power levels
 

Power levels have nothing to do with the router whatsoever.

It was very clear right from the beginning the *only* thing the OP was enquiring about were power levels.

Re: Superhub 2 Power levels
 

Yes, because what the OP was inquiring about in this thread and what the OP was inquiring about with the VM tech were not the same things. Keep up.

Re: Superhub 2 Power levels
 

Sorry to dig up an old thread but I've have a few down times lately with one lasting over 4 hours after speaking to VM they've said I have an intermittent fault but they can't send an engineer till its down again and I can give the power levels

This is what I currently have

Power Level (dBmV) -1.10 -0.47 -0.43 -0.78 -1.29 -1.67 -1.99 -2.07

RxMER (dB) 38.26 36.17 37.36 37.94 38.26 38.26 38.26 37.94

Whats peoples thoughts on the above? anything wrong with the levels?

Re: Superhub 2 Power levels
 

Power levels are fine.

Re: Superhub 2 Power levels
 

Thanks, the past 3 nights its crashed between 8pm and 8:45pm so I shall see what happens later on

What range would be classed as poor for the power / DB?

Re: Superhub 2 Power levels
 

The upstream levels are of great interest if the connection crashes. Also press refresh a few times and not if the upstream power is moving upwards in .25dBmv increments.

There is a full description of Power Levels & SNR in the Virgin Media forums.

Re: Superhub 2 Power levels
 

Same thing happened earlier with the connection just dropping out another call to VM and they are sending an engineer out

Re: Superhub 2 Power levels
 

Didn't need the engineer in the end after contacting them they found a problem in the area which was swiftly fixed yesterday

:)