I recently decided to check my wiring in terms of ADSL speed and I discovered quite interesting things:
I opened that box where a phone line comes into my house and there are four wires connected to my house (my internal cabling seems to be made of Cat5e/6 cable).
Kind of wondering why they provided four wires when only two wires are required for a phone and BB? (they are blue and white BTW)
Also on two wires (one pair - black and red) I found a ~48 VDC (+/-) to be presented and they were actually not patched to a wall socket.
So to summarize - four wires from underground are connected to four wires that go into the house. Two of them are patched to a wall socket and used for BB, the others two are NOT patched and just left wrapped around the Cat5e/6 cable in a wall socket but the have +48 VDC.
I also found that white cylinder attached to only one single wire. What is that - capacitor? Shouldn't it be connected to two wires? Should I reconnect it back (probably to a white cable?)
Can all the above make negative impact on my BB speed (I am on naked plan so no PSTN)?
Currently it is:
Upstream Bitrate Fast : 0 kbps
Downstream Bitrate Fast : 0 kbps
Upstream Bitrate Interleaved : 1128 kbps
Downstream Bitrate Interleaved : 10122 kbps
Downstream Noise Margin : 6.000 dB (48 1/8dB)
Upstream Noise Margin : 5.5 dB (44 1/8dB)
Downstream Transmit Power : 19.9 dBm
Upstream Transmit Power : 12.4 dBm
Downstream Attenuation : 29 dB
Upstream Attenuation : 17 dB
I found a DSL calculator which told me that based on line attenuation I should be getting around 14Mb/s.
There are no other phone sockets there or at least I could not find them, but I live in a rented house so can't be 100% sure.