My nice new modem is just too keen to sync high. I've got a pretty good line, but it's not quite good enough to hold 8000kbps with an acceptable error rate. I'd like to get it sync'ing around 7400-7600kbps.
I'm trying to lift the SN margin slightly to achieve this, but DTM doesn't work with the TG585v7 firmware, and I can't seem to get any changes to stick when I use telnet and the CLI to make them.
I've ftp'd the user.ini file from the modem onto my PC, edited in the following line, uploaded it back onto the modem and rebooted, in the hope that modemoption1 set to x24 will set the SN margin to around 9dB:
[ adsl.ini ]
adsl config modemoption=240000002000000006000000000000000072
but the SN margin is still 6dB after restart/re-sync, the speed is still 7800-8000, and when I telnet back onto the modem, the CLI command 'adsl debug modemoptioninfo' gives
00:00:00:00:20:00:00:00:06:00:00:00:00:00:00:00:00:72
which is the factory default setting. What has happened to the change I made?
The TG585v7 CLI is supposedly the same as the latest ST585v6 (last of the SpeedTouches).
My line stats: ADSL Max, interleaved, d/s attenuation = 36dB, target SN margin from BT = 6dB, distance from exchange = c.2km. I've had the TG585 hold 8000kbps for long enough to get a BRAS profile of 7000kbps (albeit briefly), but at that speed the FEC rate is astronomic, and the CRC rate is painfully high.
For the sake of completeness, I should add that I've got the modem's environment as clean as I can (plugged into master socket, ADSLNation filter + another filter in series, shielded modem cable, REIN sanitisation through relocation of noise sources) -- just awaiting delivery of a ferrite ring to put on the lead from the AC adaptor (and FWIW, the Thomson AC adaptor puts out hideous amounts of AM noise; fortunately it has a good long cord on the output side). So I think it's unrealistic to hope for a stable, low-error sync at 8000. Getting that speed at all with attenuation of 36dB is marginal anyway.
Sorry for the length of this post, and TIA for any help.
rwm32