BNC Cable- The Ultimate Guide You Need To Know

Choosing the proper BNC connector to suit the cable for your project usually comes with a price. The price typically needs to be an appropriate assessment of the intending cable. A major issue plaguing most corporate organizations and teams is choosing the right cable. BNC cables remain one of the most used cable types across different industries. This article presents all you need to know about the BNC cable. You will learn about Siamese cables, connectors, benefits, and applications of other types of cables.

BNC Connectors
BNC Connectors

SIAMESE CABLE: What You Need to Know

Siamese Cable

Siamese Cable

1. What is Siamese Cable?

Siamese could also be a term that features a couple of phenomena. The word is essential in describing things joined together. Technically, Siamese cables refer to a set of wires joined together with the same property. 

Siamese cable defines as a single-run cable. These cables transmit both video signals and power supply. Also attached to the side of the Siamese coaxial cable is the power cable. These types of cables usually make use of wires intended for data transfer to transfer power.

Seeing Cables During CCTV Installation
Seeing Cables During CCTV Installation

1.1 Premade Siamese Cable

Premade cables are cables built for individuals who are installing cables without buying tools and connectors. The Siamese CCTV cable that is pre-terminated with connectors already on it is easy to install. All you have to do is insert your cameras in, and you are ready to go!

The majority of the premade Siamese cables are in black or white color. These cables also come in different lengths to keep most camera cable distances. 

So premade Siamese cables create a plug and play installation and also saves time and money!

1.2 Siamese Coax Cable

This type of cable consists of a power wire and a video wire in a single-run. The cable can supply power to the device in question and simultaneously transmit the video signals to the output. They can also be customized to suit your needs by using a preferred BNC connector.

The design of a Siamese coaxial cable features both the video and power terminals. An RG59 coaxial cable transmits video signals and footages from the cameras to the DVRs. These cables achieve this transmission without a separate direct power source cable.

2.The Thickness of Siamese Cable

Siamese cables vary in their length, width, and thickness. This variation depends on the construction materials used and insulating materials. The cable’s design offers a good shielding effect on the cable, directly proportional to the wire’s thickness. 

Thicker cables usually offer better security to the loss of data during transmission. The range of thickness for a standard wire is the best.

3. Siamese Cable Connectors

BNC Connectors
BNC Connectors

3.1 BNC Connector

There are many definitions of the BNC acronym. Other names include Barrel Nut connector, Bayonet Navy connector, Bayonet Nipple connector, and British Naval Connector. Nevertheless, they are popularly known as the “Bayonet Neill-Concelman.”

Bayonet Neill-Concelman (BNC) is used as a socket and plug for video signals, audio signals, power, and networking systems. These devices are known to offer the best connection to devices. They have a powerful bond with any device of choice.

BNC Crimp-On Connectors

The crimp-on connectors install by inserting the wires. Next, they turned to ensure the whole pins get strained into a locking furrow on the plug.

BNC Crimp-on Connectors
BNC Crimp-on Connectors

BNC Compression Connectors

The BNC compression connectors are the best connector types for CCTV Security cameras. They make sure connections are never loose.

BNC Compression Connection

BNC Compression Connection

NOTE: Once you compress the BNC compression connectors, the installer cannot undo it. If there is a wrong compression, then the cable and connector are a waste. 

It is more of a reason why only professional installers are to use the BNC compression connectors. 

There is no compression without a tool. Therefore, the BNC compression connectors require the compression tools to compress the connector on the wire finely.

3.2 12V DC Connectors

12V power supply is essential in running the second cable that makes up the Siamese cable. As a rule of thumb, you will need both male and female pigtail connectors. To connect a 12V power supply, you will have to attach the pigtail connector (female) to the DVR end of your cable. There is also a possibility of connecting multiple cameras to the DVR. In such scenarios, a splitter will be crucial in splitting the power supply into channels.

A DC connector (in other words, direct current connector) is a connector for supplying power to devices. It is no news that most of the devices we use today make use of 12V DC. They work by taking any power input from 100Volts-220Volts Alternating Current (AC) and giving 12 Volts DC as an output. Devices such as LCD screens, DVD players, Hard Drives, and most other digital devices use this powerful model.

4. Benefits of Siamese Cable

4.1 Siamese cable can transmit both video signals and power in a single-run cable. The video signals run in RG59 Coaxial cable. 

4.2 Siamese cable offers freedom of length to the user. The cable can run up to 1000ft with or without amplification. These cables can also get cut to the exact size needed.

4.3 These cables are compatible with numerous devices as long as the right connector gets connected to its terminals. It can also work with crimp-on and compression BNC cable connectors.

4.4 They have a very reliable shielding. The shielding effect conferred by the thickness and the nature of the manufacturing materials minimizes interference.

4.5 The cables can come in different colors, but the most popular ones are Black and White.

5. Ethernet Cable vs. Siamese Cable

The ethernet cable is unique in its mode of power. It is similar to the Siamese coaxial cables having single power cables. Nevertheless, the Siamese cables are more cost-effective than ethernet cables.

The Ethernet cables are more compatible with all IP cameras than the Siamese cables. However, a major advantage the Siamese cable has over the ethernet cable is its data security. Without a doubt, ethernet cables also offer data security and reduce electrical interference. However, the ethernet cables are not as good as the siamese cables for this function. 

6. Premade Cable vs. Bulk Cable

The Premade Cables are usually the plug and play cables for use with security cameras and other devices. They come with their connectors in place. The Bulk Cables are cables that require tipping, cutting, measuring, and attachment of connectors to the terminals. These cables differ in quality, price, and aesthetics.

6.1 Quality 

Quality in manufacturing dramatically depends on the manufacturing materials, thickness, and cable length. Nevertheless, the bulk cable offers better quality and allows for creativity.  

6.2 The Price

Although buying your camera in bulk may appear costly, it is not always the case. You will save a lot of money in the long run, especially if you use many cables. However, if you will be using a short length of cable, the premade cable is the best.

So as a summary, go for premade cables if you will be using short cables. In contrast, go for bulk cables if you will be using long cables. By doing so, you are making a cost-effective decision.

6.3 Aesthetic

Thickness, length, shielding, and durability affects the aesthetics of the cable. The colors of the cables are usually black and white. For more comfortability, the bulk cable is the best.

7. Other Cables of Security Camera System 

7.1 VGA Cable

The VGA cables are also suitable for connecting the DVR to an external display. As a rule of thumb, there is even a possibility of using both the HDMI and VGA cables together. This functionality is important when you want to use two displays at once. All you have to do is connect your VGA cable to one display and the other’s HDMI cable.

7.2 HDMI Cable

HDMI cables allow you to connect an external display to your recorder. Like the VGA cable, they especially suit for DVR with an analog system. However, these cables are also an essential component when using NVR with IP security camera systems.

2. Understanding RG59 Siamese Cable

A Typical Cable
A Typical Cable

1. What is RG59 Siamese Cable?

The RG-59 Siamese cable is a standard cable type of cable that features tremendous video signal and power. These cables are suitable for Radio Frequency signal transmissions. 

They feature a copper braided shield used to connect to ground connections. This design keeps the shield from radiating the electrical signals. A dielectric insulator surrounds the single-center conducting center to prevent power loss over the cable run’s length. The power cables are attached to the RG59-cable side. This design is to make it a single-run cable carrying both signals and power supplies.  The RG59 cables have several uses and applications.

2. How-to Attach BNC Connector

There are different types of coaxial cables with their various associated BNC connectors. It is advisable to read the manufacturer’s instructions before starting the task of attachment. Nevertheless, here are the steps you should follow for attaching BNC connectors. 

Steps to attach BNC Connector

Putting it merely, attaching the BNC connector involves four main steps.

  1. Strip the cable of choice according to the instructions on the cable’s bag. The crimp sleeve helps to ensure proper stripping of the cable of choice, avoiding the internal components’ peeling. Check to ensure the center connector is straight and free. 
  2. Next, slide the BNC connector onto the coax cable, ensuring both fits in well. Also, ensure the cable’s braid is clearly off the body after sliding the connector in place. 
  3. After sliding the BNC connector, place the insulator onto the cable. While holding firmly to the coaxial cable and the BNC connector, click the last piece into position. 
  4. Before crimping the connector into the final and last position, do a light pull test. This test helps to check and confirm the cable’s termination to the connector’s center pin. If the test fails, the connector is wrongly placed and must have a substitute, and the termination process starts again. 
  5. Using a crimp tool, affix the BNC-connector. As a rule of thumb, you must carefully inspect the work done. This inspection is to ensure perfect working conditions. which will give the best results.

Other methods on how to attach the BNC connectors may require some soldering work. In addition to crimping methods, some have clamp nuts to be tightened to a certain degree. These nuts and clamps form as additional fail-safe methods. They ensure the BNC connectors stay in place during connecting and disconnecting from its compatible devices.

3. BNC vs. SDI Cable

The BNC connector is a plug format type of connector, while the SDI is a signal transport type of connector.

1. Definition: 

The BNC is a connector type commonly used on Siamese cables, coaxial cables, twisted cables, and other cables. It is compatible with transmitting the intended signal. The terminals of the coax cables get mounted with the male-type of BNC connectors. This BNC helps to strengthen the signals sent by the video adapter.

In contrast, Serial-Digital-Interface (SDI) connectors’ advantage lies in their transmission ability. SDI connectors can transmit a considerable amount of data, such as uncompressed and unencrypted video signals. It is a professional video standard cable developed for broadcast video operations. 

2. BNC Connectors on SDI

Unlike the BNC that is a connector format of the signal, SDI is a transport format. Because of the SDI’s use of coaxial cables, it typically features BNC plugs. SDI typically carries an uncompressed digital video signal in addition to its PMC audio. This feature allows for transmission at 75 Ohms for a coaxial cable connected to a BNC plug.

Nevertheless, SDI cables have a limited range of signal bandwidth. They typically cannot handle bandwidth tending to the gigahertz range. Hence, the BNC connector is crucial to its proper functioning.  This connector allows the SDI cables to function even at higher bandwidths.

4. BNC Camera Cable

1. What is BNC Camera Cable?

The BNC camera cable is the type of cable, such as the RG59 Siamese cable. They are typically used to transmit video signals from a camera to a DVR/observer. These cables also provide power to the camera simultaneously. 

(BNC Camera cable)

BNC Camera cable

2. BNC Video Cable

The BNC connectors usually come in 50 ohms and 75 ohms. It is the best connector used with BNC video cable assemblies. It is of the same characteristic impedance with assemblies of RG59.

(BNC Video Cable)

BNC Video Cable

5. CCTV Cable and Connector

1. Types of CCTV Cameras

Depending on your requirements, you can select one of the following cameras to suit your project.  

Different Types of CCTV Cameras

Different Types of CCTV Cameras

1.1 The Indoor Camera system

As the name implies, indoor cameras use for indoor security systems. Their design allows them to be used indoors, thereby prolonging their service life. These cameras are very reliable and are a preferred choice for schools, homes, and hotels.

1.2 The Outdoor Camera system

A Typical Outdoor Camera

A Typical Outdoor Camera

The outdoor cameras’ design features a special casing and several lens options. Most of these cameras are also waterproof. These are the types of cameras used for entry points of buildings.

1.3 The IR Day / Night Camera System:

A Typical Surveillance Camera

A Typical Surveillance Camera

IR Day/ Night Camera is a highly sensitive camera used in places where security is a concern. Like the regular camera, the IR camera displays colors at the output end during the day. But at night, the camera switches to black and white mode. 

These camera types find the best application fit in the military barracks, parking lots, garages, and high-security zones. 

1.4 The Dome Camera

Dome cameras feature a dark dome-like housing and designed to be unnoticed by observers. These cameras come in a compact design and can be tilted and rotated manually, depending on the surveillance team. 

Like the outdoor cameras, dome-type cameras are the best fit for public places. They are a common choice in railway stations and bus terminals. 

1.5 The Bullet Camera

Just as the name implies, they feature a bullet-shaped casing. These types of cameras find their application both in the indoors and outdoors environment. The bullet cameras are small in size. But they have a reputably integrated design and are useful in carrying out security surveillance. The bullet cameras also have infrared light, which offers an illuminating view even in darkness and weatherproof. 

1.5 The Vandal Proof Camera

These are unique camera systems used for security purposes. They look better when housed within a solid material covered by a break-proof glass hub. The glass hub does not reduce the camera streams’ video footage.

These cameras are suitable for security posts as they are strong. 

1.6 The Hidden Camera

It features a compact design. They are cameras that use for spy surveillance. They are best for use in places like clubhouses and stores. Their design includes a built-in recorder. This feature allows the camera to achieve seamless recording and broadcasting of footage. 

1.7 The Pan Tilt Zoom Camera

Also referred to as the 360° camera. They offer good viewing and zooming capability in all possible directions. These cameras can also work automatically to turn to a different viewing position.  

2. Different Types of CCTV Cable

2.1 Coaxial Cable


  1. Durable: These cables have tremendous service life compared to other CCTV cables. Their durability results from the efficient material used in their design.
  2. Versatile: A major concern of users when purchasing cables is versatility. Coaxial cables are suitable for a wide range of applications. You will find them in towing vehicles, RF signal transmission, as well as mooring ships.
  3. Reliable: The design and shielding used in making coaxial cables make them a very reliable option. They are not prone to data loss due to the shielding property they possess.
  4. Distance: They are suitable for signal transmission over long distances. These cables can achieve this transmission with minimal electrical interference.


  1. Cost: The design of coaxial cables makes them costlier than many other types of cables.

2.2 Siamese Cable


  1. Versatile: The Siamese cable is also a very versatile type of cable. Their design allows for both power and data transmission at the same time. Also, they are suitable for a wide variety of applications.
  2. Data integrity: These cables prevent electrical interference from causing data loss. Hence, the cables are a reliable option for data transmission.
  3. Simplicity in design: The capability of both data and power transmission make the Siamese cable popular. These cables have the added advantage of simplified operations due to its design.
  4. Adaptability: The Siamese cables are compatible with several electronic devices. You will find them in CCTVs, security systems, and even surveillance cameras.


  1. Intricacy: the Siamese cables require experienced personnel during installation and operation. This intricacy is due to their special design that allows for both data and power transmission.

2.3 Ethernet Cable


  1. Reliable: The ethernet cables are less prone to technical problems common in other types of cables. They are very reliable and have a long service life.
  2. Data security: These cables enhance data security and prevent data loss by using common firewalls. 
  3. Speed: The ethernet cables offer a tremendous amount of speed for data transmission. In addition to their speed capability, they are very secure to use.


  1. Distance: the ethernet cables offer reduced distance capability compared to other cables. 
  2. Additional requirements: The ethernet cables require a port on the switch for each wired device. This requirement might not be cost-effective for some users.

3. Analog Camera Cable and Connector

Analog Cables

Analog Cables

3.1 BNC Connector

The BNC connector is a Radio Frequency spectrum (RF) connector adapted as coaxial wire. It is adapted to connect to devices such as TV or radio and other radio-amplitude electronic equipment.

This connector’s frequencies are below 3 GHz, and the connector uses RF signal connections. The BNC is a substitute for the RCA connector when used for composite video on mainstream video devices. 


  1. They are the most common type for CCTV cameras.
  2. The BNC cables can function effectively at extremely great distances.
  3. These connectors have a firm physical connection due to their design. Unlike the DIN connector, they are less prone to disconnection and inconsistent image.


  1. Their design requires a separate power source. Hence, It might not be cost-effective.
  2. They are only able to transmit video signals.

3.2 RCA Connector

The Radio Corporation of America (RCA) connector is the oldest kind of cable. It initially invents to allow mono phonograph connectors to connect to various amplifiers. 


  1. The RCA cables are preferable for both audio and video signal transmission.
  2. These cables have several available accessories.


  1. They do not offer firm physical connections like the BNC connectors. Hence, they are prone to disconnection and inconsistent image.
  2. They are unsuitable for vast distances.

3.3 DIN Connector

If you spend more time in cars, you will probably have to replace your old car radio and cabling system. There are some things to consider before changing your car radio into a modern double DIN head unit.

Now you know that most car radios come with an inbuilt universal cable, there arises purchasing one. Many manufacturers claim that the connector that is convenient for this purpose is not the ISO. To connect any dual DIN host to your car,  it is highly advisable to buy the right adapter cable. 


  1. These connectors’ designs make them easy to connect.
  2. The DIN connector does not require a separate power source. This feature makes them cost-effective as the system easily powers them.
  3. They are capable of being used across very long distances.


  1. The pins are easy to bend. Therefore, you need to be extra careful during the connection process.
  2. It easily disconnects, especially when used for DVR systems. 
  3. The pin configuration shares compatibility with the camera manufacturer. Hence, users cannot mix DIN cameras from just any manufacturer.

3.4 BNC Extension Cable

Are you considering a more extended range for the transmission of data and power? Then the BNC extension cable is what you need. With the BNC security coupler, you will easily connect 2 BNC extension cables to extend the cable reach. It is Ideal for CCTV applications as it is simple and easy to use.


  1. They offer extended length capability.
  2. These cables are straightforward to install and offer a firm physical connection. 
  3. They allow for both video input connections and camera connections.


  1. Their design requires a different power source. Hence, it might be bulky.

How to Convert Between Connectors


As a rule of thumb, the BNC female to RCA male Coupler can improve CCTV standards. This standard is usually better than BNC to common RCA connectors.

RCA to BNC Cable

It is best practice to use the female RCA to male BNC Coupler. This practice helps to convert common RCA connectors to standard BNC CCTV cable. It achieves merely by connecting the RCA connector to the female RCA and the male BNC Coupler. Then it gets connected to the BNC connector. The observation speeds up the processes carried out by the observation system/DVRs.

DIN to BNC Cable

Here, the BNC Cable Adapter converts DIN connectors’ to standard BNC CCTV cable. Connecting the DIN connector to the BNC Cable Adapter can achieve it. Then the connection of the BNC connector to the observation system / DVR occurs. 

BNC to DIN Cable

The BNC to DIN Cable is customized using an RCA to DIN cable adapter. This adapter connects standard CCTV BNC connectors to DIN ports’. 

RCA to DIN Cable

The RCA to DIN Cable Adapter allows a connection between standard RCA connectors and DIN.                

4. Running Long CCTV Camera Cables for Your Setup

The maximum distance the CCTV cameras should be from the recorder is crucial. This distance is typically a function of the CCTV camera cables for setups. Cables such as the RG59 coaxial cable can extend the camera from 600ft to 1000ft. The RG6 coaxial cable can run up to 1300 feet. Using multiple amplifiers, the RG6 can run up-to 5000ft.  


This article has provided you with all you need to know about these kinds of cables. Nevertheless, if you need custom BNC cables with a perfect connector, you will need to choose a reliable manufacturer. Cloom Tech is the best place to get quality cable solutions. Our products meet international standards for quality, durability, and performance. You should get in touch with us for a quality BNC cable connector matching your design and specifications.

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I am a responsible, intelligent and experienced business professional with an extensive background in the electronics industry.

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