I wonder if I am misunderstanding you.

"..
Somewhere in the mobile network, or the exchange,.."

I can see that the ringing is coming from somewhere else, say the exchange, other than my phone as that is disconnected but is the noise, over the ringing sound, coming from before my line from the exchange?

If my phone is disconnected does the exchange know (say a circuit not completed by the phone) and therefore does not send any signal down my line?

is the noise, over the ringing sound, coming from before my line from the exchange?

probably the mobile network or white noise from the exchange equipment, there's no audio data to send to you from the line without a phone off the hook.

the exchange sends a ringing voltage to ring, but your line is otherwise approximately open circuit.

With VoIP you can be listening to ringing tone for several seconds before the phone starts to ring, so it's generated at the caller's system end.

The noise on the mobile is probably from teh AGC circuit on the handset. There is no audio path until the call is established so with no audio the handset amplifier ramps up and any low level internal circuit noise is amplified until audible.

Thank you for your advice.

Turned out to be my Speedtouch router.

Replaced it with a Thomson TG784 and the noise and drop outs went.

However when the Speedtouch was used I was getting 3.7 down and .37 uploads.

Now, after 11 days without any drop outs I am getting 2.5 down and .37 uploads

this is the data from the Thomson:-

Uptime: 11 days, 4:15:53
DSL Type: G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]: 448 / 4,512
Data Transferred (Sent/Received) [MB/GB]: 321.66 / 4.04
Output Power (Up/Down) [dBm]: 12.0 / 19.0
Line Attenuation (Up/Down) [dB]: 26.0 / 43.0
SN Margin (Up/Down) [dB]: 22.0 / 15.0
Vendor ID (Local/Remote): TMMB / IFTN
Loss of Framing (Local/Remote): 11 / 0
Loss of Signal (Local/Remote): 1 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 1 / 0
FEC Errors (Up/Down): 154 / 106,626
CRC Errors (Up/Down): 154 / 360
HEC Errors (Up/Down): 89 / 312

should I be getting better downloads?

Because your noise margin is so high. Do a BT speedtest to determine your profile.

BT profile:-

Download speedachieved during the test was - 3369 Kbps
For your connection, the acceptable range of speedsis 1200-4000 Kbps.
IP Profile for your line is - 3500 Kbps
The throughput of Best Efforts (BE) classes achieved during the test is - 11.05:23.04:65.91 (SBE:NBE:PBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.

The results of this test will vary depending on the way your ISP has decided to use these traffic classes.


Re-run of Thinkbroadband test now gives 3.2 down and .4 up.

Still down from 3.7 using Speedtouch router.

Note using BT line checker max is 6.

Edited by athegn (Fri 18-Feb-11 19:51:00)

Keep an eye on that noise margin. This :

SN Margin (Up/Down) [dB]: 22.0 / 15.0

is too high.

no surprise snr is high if you have been having dropouts, you can try ringing technical support and ask them to reset your line to 6db snr - tell them you changed a faulty router, this will increase your speed, if there is still a fault the snr will climb back to 12. Or you can leave alone and wait for the exchange to change you when it sees fit but this may take a little while.