RF Connector Types: Which One Is Right for Your Application?

A Closer Look at the Criteria for Radio-Frequency Components

Shopping for a radio-frequency (RF) connector is not exactly a simple proposition. On Bulgin’s online catalog, there are 25 different search categories that describe products for radio signals.

All these parameters make the selection process more complicated than choosing a power or data signal interconnect. This post offers a brief guide that can help you zero in on the best candidate in this class of component.

The Bulgin catalog gives a complete overview of RF solutions that work with a wide array of frequency levels with low losses.

Criteria for Selecting RF Connectors

Connector Type

There are various RF connector types based around size, frequency range, or industry standard. These include V-Type, K-Type, SMA, SSMA, N-Type, F-Type, and TNCA. The differences are shown in the table below. Each type may have different characteristics, so consider factors like size, durability, and ease of use.

Maximum Frequency

Different RF connectors are designed for specific frequency ranges. Connector selection should accommodate all the expected frequencies in your application. All types have a minimum frequency of zero. Maximum frequencies for various types are shown in the table below.

Power Handling Capability

Another major differentiator among the several RF connector types is the level of voltage. The connector must be able to operate at the power level of the application without overheating or causing signal distortion. The table below gives examples of series and the maximum voltage.

Operating Temperature

Key questions to consider in selection: is your application intended for indoor or outdoor use? Will it encounter extreme conditions or be deployed near heat-emitting equipment? 

In certain cases, operating temperature is an important concern and will rule out connector types not designed for your product’s environment. Below are the temperature ranges associated with each product line.

Mechanical Durability

All RF connector designs are made to exceed 500 mating cycles, durable enough for most premium-quality electronics products.

Another universal — all RF connectors employ beryllium copper (BeCu) contact pins. Beryllium copper's combination of electrical properties, mechanical resilience, and resistance to wear and corrosion makes it a superior choice for contact pins.

Materials

Nearly all RF catalog products come in a version with body material made from stainless steel passivation. Stainless steel passivation is a surface treatment process used to enhance corrosion resistance, reduce the risk of fretting corrosion, improve electrical performance, and promote long-term reliability.

Alternatively, some connector types are also come in brass with a few micrometers of gold plating. The combination of brass and gold plating offers superior electrical conductivity, excellent corrosion resistance, low contact resistance, and good durability, making it a preferred choice for many electronic connectors, especially in high-performance applications.

The table below shows the body material availability for each connector series.

Size and Form Factor

Because RF connections are designed to attach to coaxial cables, all types are compatible with standardized and widely available industry components. From subminiature series to threaded locking attachments, there remains a good deal of form factor options.

Here are the basic size and shape considerations in RF coaxial connectors:

• Pin length
• Pin diameter
• Mount hole length
• Mount hole diameter
• Thread size
• PTFE length
• PTFE diameter
• Body length

To match with coaxial cables, sizes are often referred to by the RG (Radio Guide) number or URM (Uniform Resource Management) standard, which describe the cable's dimensions and construction. Common types include RG-6, RG-59, RG-58, and RG-174, each with specific uses in terms of impedance, attenuation, and frequency range.

Special Features

Once the type and cable size parameters are known, there are other options within each type for additional locking and mounting options.

Flange mount (2-hole or 4-hole)
Connector mounts to a panel or enclosure using two or four screws for a secure attachment, commonly used in fixed applications.

Extended PTFE
A longer insulator made from Polytetrafluoroethylene to provide better voltage breakdown resistance and lower insertion loss.

End launch
The connector can be soldered to the end of a printed circuit board (PCB) for RF signals, providing a transition from the coaxial cable to the PCB.

Compression mount
Attached to the cable using a compression tool, securing the connector to the cable without soldering.

Bulkhead
Designed to be mounted on a panel or enclosure, allowing a connection to be made from the outside to the inside of the panel.

Further Assistance

Having a good understanding of the requirements of your RF application is a first step in finding a suitable connector. To find the optimal match, Bulgin is here to help.

Browse our full catalog of RF connectors, terminations, and adaptors.

Have a type in mind? Choose a specific datasheet by category.

If you have further questions about product options, consult a helpful technical expert.