In this article, I’ll teach you how to test for signals in Coaxial cables.
In my job, I have had to frequently check whether a coax cable’s signal is functioning optimally or not to ensure good internet speed and connection. When a coaxial cable deteriorates, the performance of both television and computer systems suffers, potentially rendering both inoperable.
In general, testing a coaxial cable’s signal is easy. Follow these steps:
- Examine the signal strength at the source
- Note source signal strength as the baseline signal strength
- Reconnect the source cable to the cable box
- Connect the cable to a signal meter
- Note the signal strength value on the signal meter
- Repeat steps 2 to 5 for each length of coax cable on your network
I will explore more below.
Coax Cable Testing
These detailed steps will help you test your coax cable signal strength.
Step 1: Signal Strength of The Source
Examine the signal strength at the source.
Trace your cable system to the point where it connects to your local network. Unscrew the coaxial cable from the box’s network side and connect it to the cable signal meter or coax cable tester.
Step 2: Note Source Signal Strength as The Baseline Signal Strength
As a baseline, record the source’s signal strength.
Your meter displays signal strength in decibel millivolts (dbmV). Digital meters can switch between orders of magnitude automatically, reporting in the hundreds or thousands of dbmV using the same output level, so pay attention to the scale at which the meter is measuring.
Step 3: Reconnect the Source Cable to The Cable Box
Reconnect the source cable to your cable box and follow it to its first terminating end. This can happen at a split, junction, television, or modem.
Step 4: Connect the Cable to a Signal Meter or a Coax Cable Tester

Remove the cable from the terminal to which it is connected and connect it to the signal strength meter.

Step 5: Note the Signal Strength Value
Take a signal strength reading.
Although minor signal degradation is expected along the cable, your signal strength should be roughly comparable to the baseline reading. If not, the coaxial cable must be replaced.
The red light means the cable is fine.

Step 6: Redo Steps Two Through Five for Each Length of Coax Cable on Your Network
Repeat steps 2 to 5 for each length of coax cable on your network to dash the remaining cable network.
Signal strength degrades with each passing junction and cable length, but any significant degradation suggests a splitter or cable failure. To maintain signal integrity, these failed cables and splitters must be replaced. (1)
Best Trick for Tracing and Testing Coaxial Cable
To trace and test a coaxial cable, you can use a branded and standard tool to make your job easier and faster. I’ve included some information about the best coaxial cable tester and explorer to make things easier.
Klein Tools Coaxial Cable Explorer & Tester VDV512-058
VDV512-058 Klein Tools
- It can test the coax cable continuity and map the cable at four different locations at once.
- It comes with a color-coded remote that makes identification simple.
- The LED lights indicate whether the coaxial cable is short, open, or in good condition.
- It has a lightweight and compact design that fits easily into your pocket.
- A convenient handle makes it easier to carry and operate.
Wrapping Up
I hope this guide helps you trace and test your coaxial cable’s signal quality for optimum internet speed and strength. The process is quite easy, and you don’t need a specialist to do it; just follow the steps I have stipulated. (2)
Take a look at some of our related articles below.
- Kohler voltage regulator testing
- How to test coax cable signal with multimeter
- How to test ethernet cable with multimeter
References
(1) signal integrity – https://www.sciencedirect.com/topics/computer-science/signal-integrity
(2) internet speed – https://www.verizon.com/info/internet-speed-classifications/
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