Print

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

[Weaver]

I posted something elsewhere ages back (can’t remember where) about how summer temperatures reduce dsl link speeds; we are assuming that it’s to do with temperature anyway. In late spring we start to see this, around the end of april. I’m not sure when the autumn equivalent is though. Temperatures have possibly been going down here recently, although this last week has been gorgeous.

My internet sync speeds seem to be about to rise, because I see that SNRMs are improving. If I were to resync the various lines at the right time then I might secure an improvement in speed anyway, but possibly at the expense of reliability.

[displaced]

I’m in the same boat - looking forward to the winter speed boost.

The effect is quite dramatic for me. 52-54 D/S in the summer, 60-61 in winter. I’d hazard a guess that the effect is more dramatic on longer lines (more copper to warm/cool) and even more so on lines like mine that long but not too long.

I try to keep an eye on the downstream attenuation rather than attainable sync.  Partly because I’m almost always synced above attainable anyway. Also, I take the attenuation as a better feel for the physical state of the line. 

My attenuation’s about 21-22 in summer and 17-18 in winter. I think I’ve still got a month or so down here in the south-east before it’ll be worth resyncing to get a nice stable speed!

[Weaver]

Thanks - I should have thought of looking at the attenuation. I need to find some record of exactly what it was in the summer. I was looking at the SNRM for each of my four lines and I noticed that the downstream SNRM is about 0.5dB higher than the target of 3dB, in some cases more, during the better half of the day and goes down to around 3dB at worst. It was this that started me thinking about this subject.

Current values, down / up :
    line 1: 65.0 / 41.0
    line 2: 64.5 / 41.4
    line 3: 65.0 / 40.9
    line 4: 64.5 / 41.2