How to Check Signal Strength on Comcast Internet
As with any telecommunication device, the quality of service provided is affected directly by the strength of its received signal. Your Comcast cable modem requires a certain level of signal strength in order to provide you with consistent and reliable service. Generally, signal quality is degraded by adding too many splitters or deteriorated cables. If you are having problems with your cable service and suspect the problem is signal-related, you can quickly check your signal levels within your modem's Configuration Manager.
Open your Web browser. Clear the current homepage address from your address bar.
Type "192.168.100.1" in the address bar and press the "Enter" key. This opens a Configuration Manager screen.
Click the "Signal" tab. Look at the numbers next to "Signal to Noise Ratio" in the Downstream section. While numbers over 30 indicate a strong signal, numbers under 30 are considered low.
Look at the "Power Level" in the Downstream section. While zero is considered perfect, satisfactory numbers range from minus 15 to 15.
Find "Power Level" in the Upstream section. Numbers below 55 represent a good signal. Numbers higher than 55 are indicative of a poor signal.