> > Have you tried all the improvement options with your wiring &
> > microfilter(s) - see the many postings in this ng for details?
>
> More fiddling is on my list of things to do.
I've been working on optimising.
Putting the router next to the master socket is the first step
then you can use a 6 or 12 inch RJ11 to RJ11 lead (and
run CAT5 from the router - but how you distribute from the
router is up to you).
With a long line there is nothing you can do about the
local loop, all you can work on is the SNR.
Keep all things with magnetic fields, power cubes,
the PSU for the router, as far as possible from the router.
You don't want the wiring and small signal (across
the line) tranformers on
the routers PCB picking up induced noise.
The signal level at the higher end of the frequency
range is very small.
In the domestic environment low energy lamps have
a pair of transistors oscillating as a square wave
generator nicely into the frequency range just
above audio, hair dryers with their commutator
motors are also electrically noisy.
What can happen is you get a burst of noise,
your rate gets knocked back, and it takes
3 to 5 days before it gets raised again.
So eliminate anything that can act as an aerial.
Swapping different routers in and out seems
to force a retrain, so line may come back
at a higher, but sometimes short lived rate.
My BT router gives me a lot of information
about both upstream, and downstream
parameters, Dratek only gives downstream,
though its spectrum display is useful.
Draytek with UK2 long and difficult line flash
seems the most stable. All the UK2 flash
seems to do is up the gain, probaly because
on a long high loss line there is no chance
of overloading the front end. It seems to assume
a sending end level, so by upping the gain
it reports a lower attenuation (which ain't so,
atten is a line parameter) as well as a better
SNR which is probably true as lifting the gain
probably lifts the all important top end of the
HF signal above the noise.
You can chain filters, just make sure you plug
the RJ11 into the first one.
Don't load the phone side down with too high
a REN, lowering the impedance on the phones
side seems to affect the ADSL side.
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