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AppleSauce
15-01-2009, 21:47
Hello,

I have a power level of 14dBmV, I've had an attenuator for a while now which lowers it down to between -1 and -4. unfortunately now the attenuator seems to be blocking my internet connection, weird huh?

Anyone got any ideas what could be causing it?
Joxer
15-01-2009, 21:51
What are your downstream and upstream power levels with the attenuator attached and detached?

It could be the upstream causing the problem, the SNR (Signal to Noise Ratio) is importnant too.
AppleSauce
15-01-2009, 21:54
My Downstream SNR is 40.0 dB without it attached when its attached about 37 dB, as for upstream I saw very little change.

I get these errors when it's attached: "No Ranging Response received - T3 time-out"
Joxer
15-01-2009, 22:15
That would be an upstream issue. SNR is fine so what are the upstream values? Very little difference can mean a lot.
AppleSauce
15-01-2009, 22:22
Wow just tried it again for the 4/5 time in the past few days and now internet is up and running with it on, the power levels are diffrent though here they are.

this is with the attenuator:

Downstream Lock : Locked
Downstream Channel Id : 0
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 3.3 dBmV
Downstream SNR : 39.9 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 25800000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 49.0 dBmV
Upstream Mini-Slot Size : 2

Upstream seems a little high :X
Joxer
15-01-2009, 22:27
All levels are fine there, do you remember what the upstream power was before? It should be between 30 and 58.
Peter_
15-01-2009, 22:27
Wow just tried it again for the 4/5 time in the past few days and now internet is up and running with it on, the power levels are diffrent though here they are.

this is with the attenuator:

Downstream Lock : Locked
Downstream Channel Id : 0
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 3.3 dBmV
Downstream SNR : 39.9 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 25800000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 49.0 dBmV
Upstream Mini-Slot Size : 2

Upstream seems a little high :X
Your power levels appear to be virtually spot on as my own Upstream is little different from your own and I am EX-Telewest.
AppleSauce
15-01-2009, 22:28
All levels are fine there, do you remember what the upstream power was before? It should be between 30 and 58.

yes i do, my upstream power level was the same as my downstream power level, round about 39.

Moldova: I am also Ex-Telewest.
Peter_
15-01-2009, 22:37
yes i do, my upstream power level was the same as my downstream power level, round about 39.

Moldova: I am also Ex-Telewest.

Well as I said your power levels are not to different from my own and the 331000000 frequency says you are on an EX-Telewest connection the same as myself.:)
Joxer
15-01-2009, 22:50
That would be fine too, sorry no idea what was going on there, maybe upstream SNR issue that has now been fixed.
Ignitionnet
15-01-2009, 23:01
Well as I said your power levels are not to different from my own and the 331000000 frequency says you are on an EX-Telewest connection the same as myself.:)

I have some bad news - lots of ex-ntl areas now have a 331MHz downstream as well ;)
Joxer
15-01-2009, 23:04
And that looks like an Ambit modem....
Peter_
15-01-2009, 23:07
I have some bad news - lots of ex-ntl areas now have a 331MHz downstream as well ;)

But he has stated that he is EX-Telewest and I have an Ambit 256 modem in front of me and I am EX-Telewest.
General Maximus
15-01-2009, 23:09
I am ex-ntl and am exactly 33.1
Joxer
15-01-2009, 23:10
Not in this post I hope or my eyesight is failing.
Peter_
15-01-2009, 23:13
Not in this post I hope or my eyesight is failing.

Post 8 he said he was EX-Telewest and only broadbanding has said he looks like he has an Ambit but I do have one.:)
Joxer
15-01-2009, 23:21
My eyesight is failing, but it was me that said he had an Ambit.
Peter_
15-01-2009, 23:24
My eyesight is failing, but it was me that said he had an Ambit.
You are only right, I think this calls for sleep and maybe a wipe of my glasses.:p:
Ignitionnet
15-01-2009, 23:25
But he has stated that he is EX-Telewest and I have an Ambit 256 modem in front of me and I am EX-Telewest.

Yeah just mentioning that 331MHz is not a reliable indicator anymore :angel:
moaningmags
15-01-2009, 23:26
My eyesight is failing, but it was me that said he had an Ambit.

Your eyesight is fine and yes you said it.
AppleSauce
16-01-2009, 03:08
Something is not right here, if I reboot my modem whilst the attenuator is connected I cannot connect to the internet I just get these two errors:

Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Time Not Established Time Not Established Information (7) MAP w/initial maintenance region received

But if I disconnect the attenuator whilst the modem is on and let it sync, then plug in the attenuator it works fine. :confused:

Extremely weird.
Ignitionnet
16-01-2009, 08:53
That sounds more like a boned modem to be honest.
AppleSauce
16-01-2009, 13:33
The modem is brand new, the attenuator never used to work on my old modem which was a webstar DPX100 either, it just randomly started blocking the signal one day.
Ignitionnet
16-01-2009, 14:32
Doesn't really explain why modem can sync fine so long as it's synched before hand.

Unless ofc something in the attenuator is faulty and breaks the modem's ranging downstream.

If it works fine without the attenuator just leave it out.