ADSL Sync Speed - Interesting Findings

Tesla

Tesla

Tesla

Soldato
Joined
19 Jan 2003
Posts
17,599
Location
Bristol, UK
Hi all,

I have had cable internet for years but recently moved house and am now with BT for the line and o2 for the BB.

o2 preditced a speed of around 6-7mbps.

On connecting my equipment I was getting 3-4mbps.

This morning I have set about improving this.

I removed the extension socket, I also moved the master socket to the point where the cable enters the house (there was a join at this point already).

This boosted my sync speed by around 3mbps! Just under 7mbps, EXCELLENT!

However, there's always a however or but, when I connect my telephone to the microfilter the sync speed drops to around 5.5mbps!

The telephone is a new BT DECT jobbie. Tested with the phone base station switched on (incase it was RF interference) and same result.

I have also tried a second microfilter and exactly the same. I do have some more filters so will dig those out and give them a whirl in the mean time.

Other than that a little puzzled and a quick Google hasn't helped, so, any ideas?

Cheers,

Chris
 
Tried a couple more filters, one is marginally better but no real difference. Losing just over 1mbps in sync speed when connecting the telephone.
 
tolien said:
If it drops every time you connect your phone, it's got to be your phone.
Click to expand...
The connection doesn't drop, just the sync speed. Not sure what you meant there and wanted to clarify. :)

It's improved a little actually, seems to be sitting around 6mbps now with the phone connected.

Is a drop normal, can a few other forum members with the same setup (just master socket, no extensions) do the same test for me.

Power on the modem with no phone connected, check sync. speed.
Power on modem with phone connected, check sync. speed.

Thanks a lot,

Chris
 
Sorry, should have clearly stated that I am on ADSL2+.

I may go and purchase a cheap corded phone to test. In theory a corded phone would be worse as has a REN of 1 whereas a mains powered DECT handset should theoretically be REN 0, certainly less than a bog standard phone.

I'm inclined to think it's not filters as I have tried 5 different filters that all slightly differ in appearance too so would guess the innards of the filter vary and therefore so could the results but pretty much the same with all of the filters!

Thanks guys.
 
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I am running directly through the test socket anyway. Because the master is behind a wardrobe aesthetics are not important and I just left the front panel off since it's one extra connection not required.

So the microfilter goes directly into the test socket.

I did pop to Tesco for a cheapo £5 wired phone but they were out of stock so i'll check another store up the road when I pass later today.
 
I have yet to contact o2 but have been monitoring my sync speed. It's been at a constant 6.5mb for 2-3 days now.

I guess my profile is lower since speedtests tend to come in around 5-5.5mbps?

How long does it take for the IP profile to rise (generally)?
 
Right, something to add to the mix. I lost sync. tonight whilst I was on the phone.

Does this help point to anything at all?

DSL Connection

Link Information

Uptime: 0 days, 0:14:17
DSL Type: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 880 / 6,479
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 19.0
Line Attenuation (Up/Down) [dB]: 25.5 / 47.0
SN Margin (Up/Down) [dB]: 6.5 / 7.5
Vendor ID (Local/Remote): TMMB / BDCM
Loss of Framing (Local/Remote): 12 / 0
Loss of Signal (Local/Remote): 2 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 25 / 0
FEC Errors (Up/Down): 283 / 7,426
CRC Errors (Up/Down): 283 / 423
HEC Errors (Up/Down): 54,486 / 420
Click to expand...
 
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no not yet. Will get one though. Is it possible the phone can cause sync loss?

EDIT - I note it drops out as soon as I pick up my phone to dial out. I rarely use the house phone so I expect it has been like this for some time.
 
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Finally got round to testing with a different phone and... perfect!

Sync'ing at almost 7mb, pretty much my limit (& the speed o2 predicted) and no drop outs etc.



The DECT phone is only a month old so do I return it for a different model? Or will all DECT phones cause this issue? Do you think this phone is a one-off or the model itself at fault?

Link Information


Uptime: 0 days, 0:10:33

DSL Type: G.992.5 annex A

Bandwidth (Up/Down) [kbps/kbps]: 1,213 / 6,837

Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00

Output Power (Up/Down) [dBm]: 12.0 / 18.5

Line Attenuation (Up/Down) [dB]: 25.0 / 47.5

SN Margin (Up/Down) [dB]: 6.5 / 7.0

Vendor ID (Local/Remote): TMMB / BDCM

Loss of Framing (Local/Remote): 0 / 0

Loss of Signal (Local/Remote): 0 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): 0

Error Seconds (Local/Remote): 0 / 0

FEC Errors (Up/Down): 3 / 971

CRC Errors (Up/Down): 3 / 1

HEC Errors (Up/Down): 102,109 / 0
 
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Thanks for the further replies.

Does anybody have DECT phones and an unaffected ADSL connection? If so which phones do you use?

DECT phone is really useful for us, I could run a wired extension, no problem but I would prefer not to incase it effects the sync speed.
 
Im going to take the DECT's back today and try a different make/model if the shop allow me to.
 
Right update time, the line is still dropping. Regardless of phone used.

Think it's time to call o2?
 
Bit of an update:

After having BT out twice they identified a line fault between the second cabinet on the line and the exchange. They identified the fault first time round but didn't fix it :confused:

Swapped me to a different pair between this cabinet and exchange.

Line is much clearer on the voice and so far no random hissing/scratching interference.

However, sync speed has DROPPED!

From around 6-7mbps to just 3-4mbps!

I am just on the phone to o2 but am having trouble getting through to 2nd line so making do with 1st line but it's a bit of a struggle. They're getting me to check the filter etc...

Any further ideas?

Thanks,

Chris

CURRENT RESULT
DSL Connection

Link Information

Uptime: 0 days, 0:00:52

DSL Type: G.992.5 annex A

Bandwidth (Up/Down) [kbps/kbps]: 1,075 / 3,926

Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00

Output Power (Up/Down) [dBm]: 12.0 / 17.5

Line Attenuation (Up/Down) [dB]: 33.0 / 60.5

SN Margin (Up/Down) [dB]: 3.5 / 4.0

Vendor ID (Local/Remote): TMMB / BDCM

Loss of Framing (Local/Remote): 0 / 0

Loss of Signal (Local/Remote): 0 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): 0

Error Seconds (Local/Remote): 0 / 0

FEC Errors (Up/Down): 0 / 111

CRC Errors (Up/Down): 0 / 0

HEC Errors (Up/Down): 5 / 0
Click to expand...

PREVIOUS RESLT
Link Information


Uptime: 0 days, 0:10:33

DSL Type: G.992.5 annex A

Bandwidth (Up/Down) [kbps/kbps]: 1,213 / 6,837

Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00

Output Power (Up/Down) [dBm]: 12.0 / 18.5

Line Attenuation (Up/Down) [dB]: 25.0 / 47.5

SN Margin (Up/Down) [dB]: 6.5 / 7.0

Vendor ID (Local/Remote): TMMB / BDCM

Loss of Framing (Local/Remote): 0 / 0

Loss of Signal (Local/Remote): 0 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): 0

Error Seconds (Local/Remote): 0 / 0

FEC Errors (Up/Down): 3 / 971

CRC Errors (Up/Down): 3 / 1

HEC Errors (Up/Down): 102,109 / 0
Click to expand...
Line length = ~3.5km (line test result)

The line attenuation seems to have increased a heck of an amount?!
 
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