This page applies only to the Surfboard range of cable modems, manufactured by General Instruments (GI) or Motorola.
If you send your web browser to http://192.168.100.1/config.html you will see a page similar to this one:
If you make any changes to the settings on this page, you must click Save Changes. The changes will not take effect until the next time the cable modem restarts: you may force a restart by clicking Restart Cable Modem.
On a cable system that uses a 6MHz channel spacing (e.g. NTSC colour), select North American Standard/HRC/IRC.
On a cable system that uses an 8MHz channel spacing (e.g. PAL or SECAM colour), select European PAL I/B/G.
The Surfboard might not be able to lock onto a downstream channel if the wrong Frequency Plan is chosen.
This should normally be left at 192.168.100.1.
This shows the software ID of the currently selected upstream channel, usually in the range 1-6, corresponding to the channels known as 0-5 in UBR configuration.
In the case where more than one upstream channel is available at your location, the Surfboard will, when restarting, preferentially lock on to the upstream channel whose ID is configured in this box.
If you have severe latency problems because of an over-subscribed upstream channel, you may try configuring the Surfboard to use a different upstream channel number, by setting a value in this box, then clicking Save Changes, then clicking Restart Cable Modem. Then wait doing nothing until the Surfboard has finished restarting and all four green LEDs are steadily lit. Then reload the Surfboard configuration page to check whether your selection has succeeded.
At your locality, not all the upstream channels of the UBR might be available for use, even if they are listed by the -traffic keyword of DocsDiag. Sometimes, for instance, there might be only 3 out of 6 available. In the worst case, there might be only one, the one the Surfboard is already using. There is no way you can tell in advance which of the six upstream IDs are available for selection at your location. The only thing you can do is to experiment by selecting each possibility in turn, saving, restarting the Surfboard, and checking the configuration page again to see whether (a) your selection has taken hold, or (b) the Surfboard has fallen back to a different selection.
When you succeed in changing the upstream channel in use, you should test it to see if the latency problems are any better or worse than with your original channel.
This box shows the frequency of the downstream channel, or the nearest the Surfboard could estimate to it when scanning for the downstream at its last restart. If your Surfboard takes a long time at each restart with the Receive LED flashing, or if your Surfboard event log contains many repeated entries looking like:
************ 8-Debug T509.0 Acquired DS with status NO FEC lock, DS Freq 143000000, US Id 0
with the Freq value changing on each line, then you can speed up Surboard restarts, and reduce clutter in the event log, by entering the exact downstream frequency in the Frequency box. With the correct exact frequency in the Frequency box, the Surfboard will lock on immediately to that frequency when it restarts, without scanning. You must type all the digits of the frequency (as expressed in Hz) even if they require the box to scroll in order to fit them in. If you are told the correct frequency is 402.75 MHz, you must type 402750000.
You can discover the correct frequency to set by:
For NTL in the original (not ex-C&W) regions, the correct frequency to set is 402750000, instead of the Surfboard's estimate of 403000000.
This should normally stay checked, so that the Surfboard provides a DHCP service for local use while the CATV service is not available. Disregard the sentence about being able act as a gateway for up to 32 PCs: most ISPs allow only one IP address to be alloatced in service.
If the Surfboard is connected by ethernet, no driver is required (you might need a driver for your ethernet interface card). If the Surfboard is connected to your PC by USB, then the latest drivers can be found at: http://www.gi.com/noflash/usb_drivers.asp.
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