📡 How to Check Comcast Modem Signal Levels

Guide to Diagnosing Internet Issues Using Your Modem’s Built-In Tools

📜 Overview: When and Why to Use This Guide

If you're experiencing:

• Slow internet speeds
• Frequent disconnections (especially overnight or early morning)
• Lag or buffering during video calls or streaming
• Packet loss in VoIP or remote desktop sessions

🔐 Step 1: Access the Modem Interface

1. Connect to your network (wired or WiFi).
2. Open a web browser and enter http://10.1.10.1 in the address bar.
1. If the login page does not appear, connect a laptop directly to the Comcast gateway using an Ethernet cable and try the address again.
   
2. If you don't have a laptop, or your laptop doesn't have an ethernet port, you can connect to the Comcast gateway's WiFi connection. You can find the credentials on a sticker somewhere on your gateway.
3. Login using the default credentials:
   • Username: cusadmin
   • Password: highspeed
   If these have been changed and you're unsure of the new login, please contact us.

📈 Step 2: View Signal Levels

1. Once logged in, go to Connection → Comcast Network.
2. Locate the boxes labeled Upstream and Downstream. Focus on these key values:
   • Downstream Power (Rx): Ideal range is -7 to +7 dBmV. Acceptable up to ±10 dBmV. Out of spec beyond ±15 dBmV.
   • Upstream Power (Tx): Ideal range is 35–49 dBmV. Values over 53 dBmV may cause instability.
   • Signal to Noise Ratio (SNR): Should be above 30 dB. Below 25 dB can lead to dropped connections and packet loss.

✅ For reference, see our internal guide for example values and screenshots.

📷 Step 3: Send Us a Screenshot or Photo

1. Take a clear screenshot or photo of the Comcast Network signal page.
2. Email it to helpdesk@allyadvantage.com. This will create a new ticket in our system. If you have an existing ticket, we will merge the tickets.
   

This helps us quickly diagnose whether the issue stems from poor signal quality or excessive noise.

📞 Step 4: Locate Your Comcast Account Number & Contact Support

1. Open your latest Comcast Business invoice.
2. Look at the top right of the first page — your Account Number is listed clearly under the label Account Number. It typically begins with four digits and appears in the format: XXXX XX XXX XXXXXXX.
3. To speak with Comcast Business support, call 800-391-3000. This number is available 24/7.
4. Be prepared to verify your account number and business address when calling.

💡 Tip: If you’re near your modem and can reproduce an issue while on the phone with Comcast, they can often run live diagnostics on the line and escalate a truck roll if needed.

🛠️ What Happens Next

Our team will:

• Compare your values to DOCSIS 3.0/3.1 standards
• Determine if there are power, cabling, or signal issues
• Advise on next steps such as:
  • Removing or replacing splitters
  • Using a directional tap or no-loss amplifier
  • Escalating to Comcast if the issue is external

📍 Note for Non-Comcast Modems

If you're using a non-Comcast modem (e.g., Netgear, Arris, Motorola), the interface will look different. Just email us your modem’s make and model, and we’ll send you device-specific instructions.