Does Splicing Coaxial Cable Degrade Signal?

The reason why you are looking for splicing a coaxial cable might be for your home or business, frequently cables need to be lengthened, shortened or repaired and I am pretty sure your DIY project needs you to have any of these operations done.

Well, let me assure you that you’re in the right place. I have discussed about coaxial cables and the process of splicing them thoroughly in this article.

Read it out to know more about coax cables and all necessary queries.

Shall we delay any further? Let’s just begin!


Splicing often is responsible for signal loss. Here the length of the cable plays an important role. The length of the cable directly affects the connection between the resistance and capacitance of the wire.

Besides Resistance and the dielectric field both influence the frequency of the signal of the wire, as the insulation system of the wire is created with dielectric materials. You need to utilize additional dielectric material as an insulator when you need to transmit a high-frequency signal across a coaxial cable.

The signal flow will decrease as the amount of dielectric materials rises. Hence, the signal fades.

When the cable or other media through which the energy travels is poor quality, the signal loss is occurs regardless of how successfully the signal is transferred from the transmitter. You must therefore first determine what is causing the coaxial cable signal loss.

What is Coaxial Cable?

Let’s try to understand the structure. These are electrical signal-carrying wires, which in general are useful for signals that could be interrupted by noise.

On the outermost surface, there is a protective plastic layer, inside which a braided metal mesh conductor is placed. Then there is a copper conductor shielded by an insulator around it which is just inside the braided metal conductor.

The copper conductor in the core is thus the signal carrier in this instance.

The conductor wire is insulated by an insulator, which is basically a dielectric plastic insulation layer. This also works as a separator between the conductor and the shield.

The braided metal conductor works for preventing any interruption of the electrical signal or cross-linking.

And finally, The protective plastic layer consists of a plastic polymer coating, providing additional safety, and is the final protective layer of the entire system.

These cables can be identified by two letters prefix RG followed by a number. For example, RG-9. The number indicates a rating that was developed by the US military in order to identify different coax types.

How Does Coaxial Cable Work?

The transmission of signal is incurred by copper conductors. Mainly it conducts alternate current instead of direct current.

If a regular wire is utilized in a situation where high-frequency current needs to be conveyed, the wire will emit signals outwards.  Hence, the signal will lose some of its power, which will reduce the signal’s strength.

To deal with such problems, coaxial cables can be of great use. The braided mesh layer confines the radio emitted by the conductor.

But that’s not it with coaxes. The distance between the central wire and the mesh conductive layer will not be constant if a particular segment of the cable is pinched or twisted, which will have an impact on the internal radio waves. In this scenario, the signal’s source will get a reflection of the internal radio waves. The effect lowers the signal power.

Hence coaxial cables are made with an added layer of plastic insulator between the mesh and the center wire. It ensures a reliable separation between these two layers as well as provides stiffness, which makes the cable not so easy to break or bend. 

Uses Of Coaxial Cable

Of the vast uses, I would discuss few of them for a better understanding.

Security Camera Signal

For CCTV or security camera usage, RG-59 is unbeatable. Besides, RG-6 is also vastly used though both of them have different features.

Video Signal

RG-6 and RG-59 is well known in the video industry. Here, RG-6 is always recommended to use for it’s digital signals rather than RG-59, which is basically an industry standard one.

Internet Connection

RG-6 was created run signals on a higher frequency. These internet carrying cables are made with a thick dielectric insulation and a large conductor. RG-6 cables may transfer GHz signal levels more effectively because they are made with a different type of shielding.

Television Signal

The RG 62 cables are used for televisions that work within 75 ohms. It uses RG-6 as an identifier. But today, RG-62 cables are rarely used in networking applications.


High-definition television carries stronger signals. An RG-11 coaxial cable is the ideal choice for HDTVs. Because this kind of cable needs a thicker gauge and greater room to transfer signals.

Read Also: Installing an Outlet with 3 Black and 3 White Wires

How to Splice Coaxial Cables?

Now I will instruct the step-by-step procedure of splicing a coax cable. You will need a few tools to do the job, but don’t worry. These are easily available in any hardware or electrical store near you.

Identify Terminator Point

  • Take a tiny, precise wire cutter.
  • cut off the ends of the coax cables.
  • create a squared-off surface.
  • Next, use your fingers to shape the coax’s ends.
  • Reform the cable ends into cylinders by molding them. Because of the cutting operation’s pressure, they will have been deformed.

Insert Cables

Take a coax stripper tool and insert the cables there one by one. As each cable is introduced, make sure the end is set flush against the wall or the stripping tool’s guide to guarantee precise strip lengths.


Get the stripping tool around the cable and spin the tool precisely around it 4 to 5 times. On each cable, keep the rotation in the same spot. Applying pressure that would draw on the cable insulation layer is not recommended.

Complete Cutting Strip

As you’re done with each cable, remove the stripping tool. The stripper made two cuts. Now get off the material closest to the ends of each cable. use your fingers for pulling them off.

The middle conductor of each cable is thus left uncovered as a result.

Pull off the Outer Insulation

Use a stripper and then your finger to gently pull off the outer insulation that has been freed on each cable. Each cable’s foil layer gets exposed as a result.

Tear off

A layer of metal mesh will then be visible as you tear off each cable’s exposed foil.


Now with your finger, bend the open metal mesh back on each cable. But be careful, you must not tear the layer of foil under the mesh. Each cable’s end of the outer insulation should be covered by the mesh after fully bending it back.

Know that the underlying insulation is protected by the foil.

F connector

Get an F connector and press the end of the cables into the back of it. Ensure that each connector has a white inner insulating layer resting against the connector’s front flange. Apply just straight pressure to obtain a good installation.

It might be essential to wiggle and keep pushing the coax and connector together. Be careful of the cable inside the connector’s body as it should not be twisted.


Put a coax crimping tool inside of each F connector. Connectors must be soldered or crimped. Squeeze the crimping tool handle all the way to complete the crimp. Open the crimping tool after releasing the handle.

Now you shall remove the finished crimp connection from the tool.

Complete Splicing

Now it’s time to finish off. Use a BNC female-to-female coaxial adapter to connect the ends of the 2 cables.

Why does Splicing Coaxial Cable Degrade Signal?

The loss of energy that occurs when a signal travels across a medium, typically coaxial cable, is known as signal loss or degradation.

In essence, the signal loss doesn’t depend on how well the signal is transmitted from the transmitter when the cable or medium through which the energy goes through is poor.

So, you must first understand the causes of coaxial cable signal loss.

Length of the Coaxial Cable

The length of a coaxial cable is the reason for signal losses. It is very simple to understand. Because internal factors like resistance, capacitance, and conductance are calculated according to per unit length of a cable.

As we know the relationship between the resistance and capacitance is directly proportional to the length of the cable. So, when the length of the cable increases, the resistance and capacitance also increase.

And when the resistance and capacitance increase, the flow of energy will decrease. And this is how signal losses.

For example, if you use a 50-feet length of cable you may face 20% of signal degradation. And if you use the 100-200 feet length of cable, you may lose 50% of your energy. So, to keep the signal losses in a minimal range, you shouldn’t use any cable whose length is not more than 15 feet.

Frequency of the Signal

The frequency of the signal that you transmitted through the coaxial cable is an important factor. The frequency of the signal is also related to the resistance and the dielectric field.

When the high-frequency signal passes through the coaxial cable, it increases the resistance of the cable. And when the resistance increases, it releases heat. And this heat is produced by the high-frequency signal.

Thus, it loses the signal and reduces the current flow.

The coaxial cable has insulation around the electric field. The insulation system is working like a shield. And this insulation system is created with dielectric materials.

So, when you have to pass the high-frequency signal through the coaxial cable, you need to use more dielectric material as an insulator. If the dielectric materials increase then the flow of signal will decrease. Thus, the signal drops.

If you want the minimum signal drops, you need to use a minimum quantity of dielectric materials.

Types of Coaxial Cable

Basically, the concept is very simple. Each and every coaxial cable is made with different characteristics, different capacities, and different limits. What type of cable you have to use is depending on your requirements.

If you don’t know the limits of the cable, you can’t use the cable effectively and will face signal losses.

So, these are the basic reasons for the signal degradations.

How Do You Test If a Coaxial Cable is Good?

As you know the problem of a coaxial cable, you need to know the way to test your coaxial cable whether the cable is good for use or damaged.

Test the Coaxial Cable with a Multimeter

The coaxial cable testing method with a multimeter is a very easy way to find out the cable’s continuity and current flow through it.

If you see the current passes through the cable continuously, that means the cable is working properly and there is nothing wrong with the coaxial cable. You can also find how much current passes through it.

If you see the current flow through the cable is below its normal limit, then surely there is something wrong with it.

Test the Coaxial Cable with an Ohmmeter

Basically, an ohm meter calculates the resistance of the cable. If the ohm meter is working then there will be resistance within the range of the limit of the ohm meter.

But if the resistance is out of the range of the ohm meter, that means you need to change the cable as soon as possible.

Test the Coaxial Cable with a Continuity Tester

Testing coaxial cable with a continuity tester is one of the best tools. First of all, you need to connect the cable with the continuity tester.

Then if the tester makes a beep sound that means the cable is perfectly all right. But if the tester finds any problem, then the tester will remain silent.

Test the Coaxial Cable with a Coaxial Cable Tester

To test the coaxial cable there is a dedicated tester which is known as a coaxial cable tester. You need to turn off the connection of the coaxial cable and connect with the tester.

If the signal is normal then the cable is absolutely fine. But if the signal is very low or very strong then it suggests there will be problem with the cable.

How Do You Prevent Signal Loss?

We have already known the reasons for the degradation of the signals. Now we have to know the ways to prevent signal losses.

Length of the Cable

The relationship between the length and signal losses is directly proportional. So, the larger the length, the more the signal losses. So, to avoid signal losses due to length, you need to use a cable of fewer than 15 feet.

Resistance of the Cable

When the resistance of the cable increases, the flow of the current will decrease. So, when the current can’t pass properly through the cable, it produces heat. That’s the reason for signal losses.

So, you can use the cable with a low resistance to avoid signal losses or to make the signal losses minimal.

Dielectric Materials

The dielectric material is working like a shield in the coaxial cable. But the number of dielectric materials matters.

The more the dielectric material, the more the signal losses. Because the signal can’t pass through the dielectric material.

So, as per requirements, you can use a coaxial cable with minimum dielectric materials to avoid more signal losses.

Moisture Control

Moisture can penetrate through the coaxial cable. And it may enter through the dielectric materials. If it enters through the dielectric material, it will absorb power from the signal.

Thus, it causes signal losses. So, to protect the cable from moisture, you can use coaxial cable with solid dielectric polyethylene as the dielectric material. Because this cable will be more suitable to use in any environment.

So, what if you use each and every process to minimize signal losses, but the signal losses still remain high?

If this type of problem arises then you need to use repeaters, a device that regenerates the signal, and hubs that will increase the signal strength to prevent signal losses or degradation.

Hope it sums up how you can prevent or control signal losses.

Frequently Asked Questions (FAQs)

Does It Matter what Coaxial Cable I Use? 

Yes, it impacts the type of task you are choosing to perform with the coaxial cable.

For example,RG-59 is an outdated standard and is not as effective for internet connections if you wish to use the wire for that.

 The more recent and superior standard for internet connections is RG-6. Signal interference is lessened by its multilayer shielding and thicker copper core.

What is the Transmission Speed of the Coaxial Cable?

Coaxial cable can transmit data at a very high speed around 2/3rd of the light speed or 200,000 kilometers per second.

So, you can easily understand how fast the transmission rate it has. In other words, coaxial cable’s transmission speed range is 10 Mbps (Megabits per second) – 100 Mbps. 

Even it can transmit very high-frequency signals up to 1 GHz through it. And it works 80 times faster than any twisted pair of cables.

Does the Length of the Coaxial Cable Affect the Signal?

Yes, the length of the coaxial cable affects the signal. The length of a coaxial cable is the reason for signal losses.

It is very simple to understand. Because internal factors like resistance, capacitance, and conductance are calculated according to per unit length of a cable.

As we know the relationship between the resistance and capacitance is directly proportional to the length of the cable. So, when the length of the cable increases, the resistance and capacitance also increase.

And when the resistance and capacitance increase, the flow of energy will decrease. And this is how signal losses.

What is the Maximum Distance for a Coaxial Cable?

The maximum distance that a coaxial cable can transmit a signal successfully is depending on the mode of the coaxial cable. Single mode and multi-mode coaxial cable.

The single-mode cable is expensive and it is capable of higher bandwidth and covering long distances. The maximum cable length of a single-mode cable is around 60 km.

And the maximum cable length of a multi-mode coaxial cable is around 2kms.


If a coaxial cable is “spliced” poorly, without keeping the matching impedance along the entire length, the signal will “degrade.” When the cable or other media through which the energy travels is inferior, the signal loss is irrespective of how effectively the signal is transferred from the transmitter.

Acknowledging the basics of a coaxial wire wasn’t that tough, right? I hope the article helps you to successfully manage your DIY project.

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Manuel Elmad

Manuel Elmad has always been interested in technical things. When he was just a kid, he worked in a mechanical shop and learned all about the inner workings of electronics and machines. This sparked his thirst for knowledge and led him to pursue a career in this field. For the past 8 years, He has been working as a technician and loves to learn new things and also helps others to learn. In his spare time, Elmand likes to strike on the keyboard for spreading his knowledge and go hiking with his friends.

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