SMA vs. TNC: Two most common antenna interfaces

About SMA vs. TNC, Have you ever observed the external antennas?

The newly purchased antennas must match the radio interface; otherwise, they will not work correctly.

You may think they are all the same, but you will see different antenna interfaces if you notice them closely.

This article will introduce two commonly used antenna interfaces; SMA and TNC.

Commonly used RF connectors for antenna:

RF connectors play an important role in any antenna system, functioning as a connection between the antenna and related RF systems. 

The antenna market deploys SMA and TNC RF connectors for a rugged connection with several variants, including reverse polarity, non-rotating, rotating, and male/female options.

People use RF connectors for several reasons, but the common ones are their inexpensive nature, capacity to handle different operating frequencies, RF power levels, and large mating cycles.

SMA Vs TNC: Pros and Cons

SMA (m) RF connectorTNC (m) RF connector
Advantages:Can handle 18GHz max frequencyWeatherproof on proper matingSmall size, ideal for specific applications requiring less size and less weightMore than 500 mating cyclesAdvantages:Can handle 11 GHz max frequencySuitable for rugged applicationsWeatherproof on proper matingMore than 500 mating cycles
Disadvantages:Not very robust in comparison to large RF connectors.Disadvantages:Larger and heavier than SMA connectors

SMA antenna interface:

SMA stands for subminiature version A, and you will find them in two versions, SMA and Reverse Polarity SMA, based on the difference in the polarity.

The basic difference between SMA and RP-SMA is that SMA has an outer helix with a hole and an inner helix with a needle, while RP-SMA has an outer helix with a needle and an inner spiral with a hole design.

SMA connectors

SMA connectors

TNC antenna interface:

Standing for Threaded Neill-Concelman, TNC is thicker than SMA.

Further, a metal shield is present between the antenna connector’s outer and inner contact points.

Remedial measures:

Suppose you forgot to check the antenna interface type while purchasing. What will you do?

You can use an interface adapter to convert SMA to TNC and vice versa.

SMA Vs. TNC: Importance of RF connector quality to Antenna Performance

Due to its functionality, a high-quality radio frequency connector is critical for the antenna design.

  • RF connectors establish a connection between RF systems and antenna
  • RF connectors are a conduit for flowing radio frequency energy between RF systems and the antenna’s radome elements.

If the RF connector does not work, it becomes the main reason for the antenna failure.

Some antennas may have additional mounting structures like flange bases for added stability, but most omnidirectional antennas use RF connectors as their mechanical connection point to date.

While designing the antenna, if one overlooks the importance of RF connectors and picks some poorly designed and low-quality products, it may affect the electrical performance of the antenna design in various ways.

It can lead to mechanical failure in the antenna, which may result in communication, video, or data loss at any time.

Also, it may be life-threatening for military personnel and people who depend on wireless communication systems for their safety, security, and mission and success.

Further, it would be best always to choose the RF connectors compatible with the antenna’s intended application.

You must know that an SMA connector is suitable for commercial or indoor RF applications, not outdoor rugged military use.

For extreme environmental conditions, you must look for RF connectors that can withstand abusive weather conditions, take more space on the radio face, and weigh more.

The SMA cables

SMA Vs. TNC: Some of the performance considerations you must look for

RF connectors must meet electrical and mechanical requirements for satisfactory performance.

Often, people overlook specific considerations and end up buying low-quality RF connectors.

The connection between the RF connector and the RF cable: Crimped or Soldered

Industries use high-quality soldering techniques to solder an RF connector to the antenna cable within the antenna’s radome.

During soldering, technicians solder the connector’s center pin to the antenna cable’s center conductor.

The connection should be robust enough to ensure a long-lasting connection between the two components, especially in the case of a solid cable.

Further, the chances of the solder connection deteriorating are bleak.

Also, soldering the connector’s solder shank with the cable ground shield rather than crimping improves the mechanical integrity and performance of the antenna.

The soldering materials must be compatible with each other and should be of high quality while soldering the RF connector and the RF cable.

A stainless-steel solder tank is best suited for RF connectors for the rugged and long-lasting solder joint.

Plated finish quality on external surfaces:

Whether or not an RF connector will survive in a particular environment depends mainly on its plated finish.

Industries specify using nickel-silver (high quality) or black chrome finish for maximum standard RF connectors to ensure good mechanical performance while withstanding harsh environmental conditions; also, the center pin surface should have gold plating.

Black Chrome exterior connector plating:

Law enforcement and military applications use low-visibility, non-reflective product finish.

Thus, black chrome plating for the exterior surfaces of the connector is best suited for primary RF connectors.

When applied to a connector, a black chrome finish becomes its integral part and does not wear off quickly.

Further, if you want to remove it, there is a low-toxicity chromium and cadmium removal process, making the connector safe and environmentally friendly.


Although there are several remedial measures, we recommend choosing the type of antenna interface before buying as it can heavily impact the radio performance.

If you cannot decide which connector will be suitable for your antenna applications, contact Cloom professionals.

We are a leading manufacturer of various cable assemblies and wiring harnesses for different applications.

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