How to Tell if a Coax Cable Is Faulty (2 Methods Guide)
Content
In this article, I will teach you how to identify a bad coax cable in just a few minutes.
As an experienced jack-of-all-trades, I use several tricks to check the condition of coax cables. I will teach you the best from this guide. Damaged coaxial cables come with many problems, including but not limited to encrypted signals or poor internet reception. Finding the root cause is vital, not just assumptions for making decisions.
In general, you need to follow a few simple steps to diagnose if a coax cable is good:
- Plug the DSS01 coax cable tester into the coax socket and press the button to test it.
- Perform a continuity test with an electronic multimeter.
- You can also check capacitance, resistance, and impedance with an electronic multimeter.
I'll tell you more below.
How to Diagnose a Faulty Coax Cable
It is very important to establish the condition of your coaxial cable. This will help you identify the real problem and not speculate. You can use several methods to check if your coax cable is good or bad. I will go into detail about some of these techniques.
Method 1: Using a multimeter
You can use a multimeter to check if your coax cable is bad.
A multimeter tests the capabilities of various parts of an electronic device through many complex calculations.
Perform the following tests on the coax cable:
Continuity test
The following steps will help you:
Step 1: Install the multimeter
Insert the red probe lead into the jack with a V next to it and the black probe lead into the COM jack.
Then set the multimeter to the value of the "Ohm" parameter by rotating the selector dial. Finally, ping the probe wires; if the multimeter beeps, there is continuity between the probes. Now let's start testing the coaxial cable.
Step 2: Check the connectors
Coaxial cable has no polarity.
Touch the probe wires on the two coaxial cable connectors. If the multimeter beeps and reads less than 1 ohm, then there is continuity in your coax cable. If the reading exceeds one ohm, your connectors are faulty.
Step 3: Check the wires inside the connectors.
Touch the pins on the inside of the two connectors again. Any reading below one ohm means your coax is good.
Resistance test
Here, an electronic multimeter will test the voltage of the coaxial cable shield and other cable components. The display will show responses/readings in HMS (hectometers).
Step 1. Set your multimeter to resistance mode
Step 2. Insert a 50 ohm dummy load into one jack. Then touch one lead of the probe to the surface of the other connector and the other lead to the inside of the same socket—no dummy load.
Step 3. Compare your resistance results with the nominal impedance of your coax cable.
Capacity check
Again, use an electronic multimeter to check the capacitance of the jacket and conductor of the coax cable. Calculations will be in picofarads (pf).
Procedure: With the multimeter switched to resistance measurement mode, touch the leads on both ends of the coaxial cable and note the reading, which will be very small - in picometers.
Inductance Test
You can use an electronic multimeter to check the inductance of the shield and the line of the coaxial cable. When testing inductance, nanohenry (NH) and ohm (ohm) solutions are discussed.
Signs of a damaged coax cable
Rustic Connectors – If rust appears on the ends of your coax cable, the coax cable is most likely defective.
Missing components indicate a problem with the coax cable.
The green color of the coaxial cable connectors also indicates damage.
Weak connectors – If you twist the connectors on a coaxial cable and feel like they are loose, they are damaged.
Open wires – If the strands inside the coax cable are visible, it is damaged.
Damaged plastic tube (also called rubber shield) – If the rubber shield is damaged, your coax cable may be defective.
So, if you notice any of these signs, use an electronic multimeter to confirm.
Note: The earliest detection method for testing coax is to see if they have already failed.
Coaxial cables are made by a wide variety of companies, so their quality varies greatly.
Method 2: Using the DSS01 Coax Cable Tester
I recommend using the DSS01 Coax Cable Tester to check for problems with your coax cable. With this equipment, you avoid purchasing or using the following:
- Troubleshooting signal reception
- Troubleshooting signal transmission
- No multimeter needed
- Coax Cable Tracking
- Continuity test - on coaxial cable.
- All you need is the DSS01 Coax Cable Tester!
How to use the DSS01 coaxial cable tester
Follow these simple steps to test your coax cable with the DSS01 tester:
Step 1. Connect the DSS01 Coax Cable Tester to a coax socket.
Step 2. Click the Test button. The results will appear in a few seconds.
The DSS01 coaxial cable tester saves time and money. All you need to know is how to connect the coaxial socket and the test button - it's easy to use.
Common Problems Affecting Coaxial Cables
I have chosen four main causes of coaxial cable failure. Avoid them to ensure the long life and overall safety of your coax cables.
Thermal damage
The melting point of coaxial cables is 150°F. This is a relatively low melting point. So, coaxial cables are vulnerable to high temperatures. (1)
hints: To avoid heat damage to the coaxial cable, keep it away from heat sources. If you don't, the rubber shield may melt, pushing the components (in the cable) out of place.
Water damage
Most electrical devices are vulnerable to water. Coaxial cables are no exception. Electrical wiring and components may fail if exposed to water. Therefore, keep the coaxial cable away from water.
physical distortion
The screen of the coaxial cable is fragile. The delicate sheath of the cable can break if thrown, rough handled, or carelessly bent. Always route cables straight ahead. The slightest bend or kink can cause the innards of the coax cable (or internal components) to fall out.
Damaged connector
A damaged connector can lead to failure of the coaxial cable.
The cables are equipped with connectors at both ends. Connectors transfer information from one source to another. Therefore, changing either of the two connectors degrades the function of the coaxial cable. Fortunately, if you find problems, you can replace the connectors instead of buying a new cable. And, of course, this is the main reason for the failure of coaxial cables. (2)
Take a look at some of our articles below.
- How to check the signal of a coaxial cable with a multimeter
- Multimeter continuity symbol
- How to cut an electrical wire
Recommendations
(1) melting point - https://chemed.chem.purdue.edu/genchem/topicreview/
bp/ch14/melting.php
(2) coaxial cable - https://www.sciencedirect.com/topics/engineering/
coaxial cable
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