Whatever splitter you use, make sure that the cable modem's signal power
remains below 55dBmV for the upstream level and not too much below 0dBmV
for the downstream. Otherwise, you might have problems with your
Internet or VOIP service.
The web server built in to TWC's standard-issue Motorola cable modems
will display this information if you type (or paste) the following
address into your web browser: <
http://192.168.100.1/>.
It's best to check signal levels during the warmest part of the day. If
necessary to preserve good signal levels for the modem, put it on the
preferred (-3.5dB) leg of the three-way splitter or even use a couple of
two-way splitters in series, with the modem connected to the first
(upstream) splitter.