Superhub Randomly Rebooting Superhub - Very Annoying - Page 3

Sephiroth · 26-12-2011, 09:01

VM, as you've seen, are aware of a firmware issue that causes the SH to reset to default values when in router mode.

My engoneer's mnd tells me that where there are similar cases, one should compare production batches. If somwthing's mis-tooled, yoiu can imagine a dry joint that expands to work by day and glitch when the house cools down. Something like that. But that's musing and too much to hope for.

If there is no prodiction fault, then in modem mode, it doesn't happen unless there is a line condition and then the SH won't go to default settings. That much is clear from the VM forum (as I see it) and my own case and various other specific people have commentted likewise.

The one thing I do recommend is that you stay in modem mde with your own router. I don't think that VM/Netgear will sort oit the router mode problems any time soon.

Superblade7 · 31-12-2011, 07:06

Hi Seph,

New SH arrived on Thursday and I installed it that night.

Tried connecting via wireless and initially had problems connecting. Wired it up, dropped the 802.11 mode from 300Mbps to 145Mbps and this sorted it as everything connected and worked fine.

Then switched to modem mode and it has been in this since as my laptop is wired to it and I only need the wireless occasionally for other devices. This has currently got a System Up Time of just over 1 day and 10 hours which is the longest I've had since end of Nov / early Dec so at present (although I don't want to tempt fate) all seems to be working well.

Another additional and unexpected bonus is the quiet. The old SH always had a sort of high pitched squeal coming from it that others have reported and appears to be something to do with the power cable whereas this one hasn't.

The one thing I'll keep an eye on are the downstream power levels. The old hub was reporting the 5 channels all at 6.X dBmV whereas the new one is currently showing the 5 channels ranging from 8.6 - 9.3 dBmV. Are these levels within tolerance or a little high? May they just settle down given a bit of time? I've still got a 6dB attenuator attached and wondered whether this may need swapping for a 10 dB attenuator although I know this will require another tech visit as I know they won't just send one of these out.

So far so good, let's hope it stays that way.

Cheers

Superblade7

Sephiroth · 31-12-2011, 09:40

You can buy the 10 dB FPA on ebay if you want it quickly - they won't send one out. I don't like power levels outside the recommended range. My VMNG300 wouldn't sync at 7 dBmv. After the SH went in they had to change or reslope the street cabinet amplifier (50m away) because that had gone the other way with power down to -8 dBmv.

If you need an engineer, it's to check what's coming out of the street cabinet amplifier. If your read the Power Levels sticky, it explains all that and the effect of coax distance from the street cabinet.

Keep us posted.

Superblade7 · 01-01-2012, 09:11

Morning Seph,

Happy New Year to you and everyone else on CF.

Thanks for the advice again. The VM Forum Team did ask me to post back on there following receipt of the new SH so I'll tell them what I did on here and advise everything appears well at present (currently 2 days 12hrs and a bit up time!!!) other than the power levels being slightly high and let them check remotely and see what they think. If they don't believe an engineer is necessary might look to buy a 10dB FPA on ebay. I think it's worth waiting for them to check as they might need to check the street cabinet as you advise.

With regards to the FPA's, I have actually got another 6dB one that an engineer left me a couple of years ago when I had a fault with my TV service and he checked my BB at the same time and said I no longer needed it after what he'd done but left it with me just in case. Would this be any good at reducing my power levels (i.e. does 2 x 6 dB make 12dB) or would having two 6dB ones not be any different from the one? Not sure how they work or even if you can have 2 on a line.

Cheers

Superblade7

Sephiroth · 01-01-2012, 09:26

2 x 6 dB screwed in series make 12 dB. Perfectly acceptable.

kwikbreaks · 01-01-2012, 09:35

Except that the downstreams after the extra channels were added are now showing ~ 6-7dBmV which the SH should be able to cope with anyhow and would only require a single 6dB attenuator to take it close to 0dBmV. Adding two at that level would probably make it worse.

Sephiroth · 01-01-2012, 10:00

From post #32 I calculated that 9 dBmv minus 12 dBmv = -3 dBmv (which is OK). As temperature falls (which it may do during the winter, power will creep up towards zero. When the weather warms, one of the 6 dB FPAs can come off.

Equally so, 9 dBmv minus 6 dBmv = +3 dBmv. Power won't creep up higher than 6 dBmv as temparature falls. So that's OK too.

Superblade7 · 01-01-2012, 10:31

Kwik,

Seph is right, my current levels as in post #32 are showing at around 9dBmV with a 6dB FPA already on there so another 6dB should take it down to around 3dB which is right in the middle of the preferred levels.

However, I'm going to leave it as it is until VM have checked it from their end as it may need something tweaking in the street cab as Seph suggests rather than extra attenuation at my end.

It's stable at present so can afford to wait for 5 days or so for the VM forum team to respond.

Cheers

Superblade7

kwikbreaks · 01-01-2012, 14:19

I didn't spot that you'd just mentioned levels rather than posted the full stats or that you'd still got the 6dB FPA in line - sorry.

It seems they haven't finished tweaking you area either as the levels keep changing. At least you've got a choice of what to use though.

Superblade7 · 01-01-2012, 15:35

Yeah, the power levels seem to have shot up recently as I've not needed any FPA on for the last couple of years. Can only assume that this is something to do with them prepping my area for 100Mb.

Sephiroth · 01-01-2012, 20:47

The power levels at your modem are entirely a matter for how your street cab amplifier is set up. I've got a sticky post in the 30/50/100 meg sections of the VM forum that explains all this.

Superblade7 · 02-01-2012, 06:07

Seph,

I read your sticky following your previous post and it explains things clearly. In your first post on this thread you mentioned about the new line card and field work, would this involve them working on the street cab down my road and would they have turned the amplifier up for any particular reason (100Mb?).

Sorry if I'm being a bit slow but as well as sorting out my SH problem, your posts have also been very informative and I've learned a bit about how the network actually works so thanks for all your help.

Cheers

Superblade7 · 02-01-2012, 08:32

Just a quick update, rather than waiting for the VM Forum Team I thought I'd give them a quick ring on the tech support line as I know the Forum take about a week to respond and the tech visits can sometimes be a week or so before they come out.

Told the chap (Neil) that things seem to be working fine but the downstream power levels were a little high. He asked what the levels were and I said around 9dBmV and he asked if everything was working ok. I said yes and he said that I don't need to worry about it!

So I said that I thought that the levels should be within the -3 to +7 dBmV range and he said that whilst they are the preferred levels, he has seen them as high as +14dBmV and still work ok so unless I have any issues, don't worry about it.

So I'll leave it at that then and see if the VM Forum Team offer anything different.

Thanks again Seph for all the advice and to the other who have also chipped in.

Superblade7

Sephiroth · 02-01-2012, 08:47

Neil's spot on. But I'll answer your question from post #42.

They'll reslope the amplifier (you can Google that!) in the street cabinet if the frequency plan changes. They'll also do things if it is evident that, for example, people are having high downstream and high upstream power; again, a reslope exercise. Also if people close to the cabinet have low power, then the amplifier has to be renewed or repaired.

kwikbreaks · 02-01-2012, 09:17

Quote:

Originally Posted by Sephiroth

The power levels at your modem are entirely a matter for how your street cab amplifier is set up. I've got a sticky post in the 30/50/100 meg sections of the VM forum that explains all this.

When this area was tweaked (not sure exactly what was done) I ended up on different channels, a different CMTS, and there was a significant change in upstream power with downstream being pretty much unchanged. What wasn't changed was the congestion

I've also had an instance when an installer/engineer for somewhere else in the street swapped the tap I was on screwing up my upstream power - I reported that on the forum and got it restored to within spec.