SMA Connector Guide: Types, Specs & How to Choose

Sep 29,2025

How do I choose the right SMA connector?

Selecting the right SMA connector isn’t just a matter of matching thread sizes. Engineers and buyers usually look at impedance, voltage rating, frequency range, and mechanical durability before making a decision. Understanding the different sma connector types—male, female, jack, plug, PCB-mounted, or even waterproof models—helps avoid costly mistakes later on.

TEJTE’s SMA series covers 0–18 GHz, with designs tested to handle 335V rms working voltage and 1A current capacity. Many models also reach ≥500 mating cycles, making them reliable for consumer networking gear as well as aerospace equipment. It’s this blend of frequency stability and durability that separates a robust connector from a disposable one.

Connector types: SMA Male, SMA Female, SMA Jack, SMA Plug

SMA Male Connector – has external threads and a center pin. You’ll see it most often on assemblies such as RG316 SMA cables.
SMA Female Connector – designed with inner threads and a receptacle socket. TEJTE uses gold-plated beryllium bronze contacts, ensuring ≤5 mΩ resistance and long-term corrosion resistance.
SMA Plug – often interchangeable with “male” in datasheets. It’s the movable half that fits into the jack.
SMA Jack – the fixed part, mounted to panels or PCBs. A straight SMA-KE jack withstands 1000V rms and operates from -65°C to +165°C, making it suitable for industrial or medical devices where conditions are less forgiving.

Use cases: PCB, antennas, adapters

PCB integration – In compact circuit layouts, board space is always a concern. This is where sma pcb connectors stand out. Right-angle jacks make routing easier when vertical clearance is tight. TEJTE’s SMA-KWE right-angle jack, for example, withstands 1000V rms and achieves ≤0.15 dB insertion loss at 6 GHz, ensuring stable performance without taking up too much room.

Antennas – Many WiFi, LTE, and GPS devices rely on SMA female ports, so pairing them with the correct sma male connector cable preserves the 50Ω impedance across the system. For outdoor installs—think 5G modules on rooftops or IoT gateways exposed to the elements—using an IP67-rated sma waterproof connector is not optional, it’s essential. Without sealing, even a week of humidity can degrade performance. For more antenna-related insights, see TEJTE’s WiFi antenna guide.

Adapters – Different systems don’t always share the same interface. That’s why sma connector types also include adapters—bridging SMA with BNC, N-type, or TNC connections. TEJTE offers SMA to BNC adapters and other couplers that let engineers connect mismatched systems quickly, without redesigning entire cable runs.

What are the differences between SMA connectors?

Even though they share the same family name, sma connector types serve different functions depending on how they’re built and where they’re used. Some are cable-mounted and exposed to repeated handling, while others are fixed on panels or PCBs, designed to withstand vibration and stress. Knowing the distinction helps avoid mismatches that can compromise system reliability.

SMA Male vs SMA Female connection types

SMA Male Connector (plug) – includes the center pin and external threads. It’s normally mounted on cables, making it more prone to wear or bent pins if handled roughly.
SMA Female Connector (jack) – has a socket and internal threads, often fixed to boards or equipment housings. TEJTE’s sma female connectors use gold-plated brass housings with beryllium bronze sockets, offering ≥5000 MΩ insulation resistance and ≥500 mating cycles for consistent, long-term use.

SMA Plug vs SMA Jack performance comparison

SMA Plug (male) – usually cable-mounted, making it the “moving half” of the connection. Because of frequent connect/disconnect cycles, it tends to wear faster.
SMA Jack (female) – panel- or PCB-mounted, better at resisting vibration or mechanical stress in industrial environments.

Electrically, both maintain the required 50Ω impedance when properly matched. TEJTE’s SMA-KE straight jack operates across DC–6 GHz with a VSWR of 1.10:1, proving its reliability in RF communication boards, test instruments, and rugged systems.

For more context, TEJTE’s male vs female guide provides diagrams and real-world examples to avoid confusion in connector selection.

How do I check the impedance and frequency of SMA connectors?

A connector may fit mechanically yet fail electrically if its impedance or frequency rating is overlooked. With sma connectors, these two specs determine whether your system will run smoothly or suffer from mismatched losses and unstable performance.

Impedance standards: 50Ω vs 75Ω

50Ω SMA connectors – standard in RF communication, IoT modules, and lab instruments. TEJTE’s common sma connector types for RG316 and RG174 assemblies maintain this impedance, supporting broadband wireless and measurement needs.
75Ω SMA connectors – found mainly in video and broadcast applications.

Even though 50Ω and 75Ω screw together physically, mixing them creates reflection and mismatch losses. That means degraded throughput and potential device malfunction. For a deeper explanation, see TEJTE’s RF coaxial cable guide, which details how impedance affects system reliability.

Frequency matching: DC–6 GHz vs higher frequencies

Standard SMA models – perform reliably up to 6 GHz, covering WiFi, LTE, and Bluetooth.
Extended-range SMA connectors – precision-machined with PTFE insulation, stable up to 18 GHz.
Stainless steel SMA for RG405 – designed for aerospace; rated at ≤1.25 VSWR with shielding effectiveness ≥100 dB @ 1 GHz.

Specification snapshot

Parameter	Value
Frequency Range	DC-6 GHz
Withstand Voltage	1000 V rms
Insertion Loss	≤0.15 dB @ 6 GHz
Mechanical Durability	≥5000 cycles
Insulation Resistance	≥5000 MΩ

Practical note: in lab testing, cheaper connectors often claim “18 GHz” but fail to maintain acceptable VSWR above 10 GHz. Always confirm the datasheet and supplier’s test report before deploying in high-frequency systems.

What dimensions and specs should I consider when selecting SMA connectors?

Choosing sma connectors isn’t only about electrical ratings. The physical build—length, thread size, orientation—determines whether the part fits securely and maintains shielding. Overlooking these details often leads to misalignment, poor strain relief, or even broken solder joints after a few cycles.

Standard dimensions for various applications: straight, threaded, right angle

Straight SMA connectors – best for inline panel or PCB connections. TEJTE’s SMA-KE straight jack measures 13.5 mm in length with an 8 mm tooth size, tolerates 1000V rms, and supports -65°C to +165°C operating ranges.
Right-angle SMA connectors – widely used where vertical clearance is tight. The SMA-KWE right-angle jack measures 23 mm in total length with a 17 mm tooth, and maintains ≤0.15 dB insertion loss @ 6 GHz, making it compact but high performing.
Threaded bulkhead connectors – lock in place with nuts and washers, ensuring vibration resistance for automotive, aerospace, or heavy machinery setups.

If you’re not sure which layout works best, TEJTE’s SMA right-angle adapter guide provides examples of when angled connectors outperform straight versions.

Compatibility between connectors and cables

Every cable has its own diameter and shielding requirements, and not every connector matches them. TEJTE provides sma connector types tailored for the most common coaxial families:

Cable Type	Recommended SMA Connector	Frequency Range	Key Notes
RG174	Standard crimp SMA	DC-3 GHz	Very flexible, but higher loss
RG316	Straight or right-angle SMA	DC-6 GHz	Strong shielding, tight bend radius
LMR-200	Bulkhead SMA connector	DC-6 GHz	Low loss, weather-resistant jacket

Physical photo of SMA connectors installed on an electronic circuit board — SMA Connectors on PCB

For PCB designs, sma pcb connectors with through-hole pins give a strong solder bond, while crimp-style versions remain the go-to for flexible cable assemblies.

How do I properly crimp SMA connectors?

At first glance, crimping an sma crimp connector may seem straightforward, but it’s one of the most common points of failure in RF assemblies. A sloppy crimp introduces unwanted insertion loss, while an over-tightened ferrule risks damaging the dielectric. Following proper standards ensures stable performance and prevents costly rework later.

SMA Crimping Standards

Field	Recommended Standard
Tool Type	Ratcheted hand crimper (manual) or pneumatic (automatic)
Crimp Depth	2.5–3.0 mm depending on connector series
Conductor Strip Length	3.0–3.2 mm (inner conductor)
Dielectric Cut	Flush cut, no nicking
Ferrule Crimp	Hex crimp, uniform, no visible gaps

Step-by-step procedure

Strip the coax cable – expose the inner conductor (~3.0 mm) and dielectric carefully. A clean cut prevents micro-cracks in the PTFE insulation.
Insert the conductor – slide it into the connector pin. Depending on the design, soldering may be optional.
Position the ferrule – pull it over the cable braid to secure shielding.
Seat the connector body – make sure the pin is fully inserted and aligned.
Crimp the ferrule – use the correct die size to form a tight, uniform hex crimp (2.5–3.0 mm).
Inspect visually – check that the braid isn’t loose and the pin is centered.
Test electrically – confirm continuity with a multimeter, and check there’s no short between pin and shell.

For more examples of crimped assemblies in practice, see TEJTE’s SMA adapter options, where connectors are often paired with flexible cables like RG316 and RG174.

What are the common mistakes when selecting SMA connectors?

Even experienced engineers sometimes get tripped up when working with sma connectors. The mistakes may look minor at first, but in RF systems they often lead to degraded performance, downtime, or expensive replacements.

Verifying connector polarity (straight vs reverse polarity)

A common error is confusing standard SMA with RP-SMA (reverse polarity). Both use the same thread, but the center pin/socket arrangement is swapped. For example, an RP-SMA male has a socket instead of a pin, which won’t mate properly with a standard SMA female. Mixing the two is a classic source of frustration in WiFi antenna projects.

Practical note: always check the datasheet images or pin diagrams. More than one technician has ordered “SMA male connectors” only to discover they needed RP-SMA for the router port. TEJTE’s male vs female guide illustrates these subtle but costly differences.

Outdoor and waterproof considerations

Another frequent oversight is underestimating the environment. Standard connectors may perform perfectly indoors but fail quickly outdoors. Moisture creeps into the threads, corrosion sets in, and insertion loss rises sharply.

For antennas mounted on rooftops or 5G small cells, you’ll need an sma waterproof connector. TEJTE’s IP67-rated versions include silicone rubber seals, gold-plated contacts, and have been tested to ≥5000 MΩ insulation resistance and 1000V rms withstand voltage. These features aren’t luxuries—they’re survival requirements in harsh weather.

Related reading: TEJTE shares real-world antenna practices in the WiFi antenna guide, showing how connector choice impacts both indoor and outdoor system stability.

How do SMA connectors perform in antennas and communication devices?

The role of an sma connector for antenna systems goes far beyond simply attaching a cable. A mismatched or low-quality connector can raise VSWR, introduce extra insertion loss, and ultimately reduce coverage. On the other hand, a well-chosen connector maintains signal clarity and ensures long-term reliability.

Antenna-SMA connector matching requirements

Most antennas—whether WiFi, LTE, or GPS—are designed with SMA female connectors. To keep the impedance at 50Ω, these must be paired with sma male connectors of equal quality. TEJTE’s antenna-grade SMA series supports DC–6 GHz for standard applications and up to 18 GHz for specialized systems, all while maintaining ≤0.15 dB insertion loss @ 6 GHz and ≥5000 MΩ insulation resistance.

For outdoor antenna installations, such as pole-mounted 5G modules or weather stations, an IP67 sma waterproof connector is the safer choice. Equipped with silicone seals and gold-plated contacts, they prevent corrosion even after prolonged exposure to rain or humidity.

Applications in wireless communication systems

WiFi routers & access points – use SMA female ports for detachable antennas, giving flexibility in coverage upgrades.
4G/5G modules – rely on SMA for consistent RF links in both consumer and industrial equipment.
GPS receivers – compact SMA jacks help maintain low noise and accurate positioning.
IoT devices – miniature boards often integrate sma pcb connectors, ensuring reliable wireless connectivity even in dense layouts.

For broader antenna-related insights, see TEJTE’s WiFi antenna guide, which explains how connector choice interacts with different frequency bands and device types.

How do I assess the quality and reliability of SMA connectors before purchase?

Not all sma connectors are created equal. Two connectors may look the same, yet their internal build, plating quality, and test standards can lead to very different lifespans. Before committing to bulk orders, it’s worth checking certifications, materials, and real test data.

Quality certifications and brand selection

A reliable connector should meet RoHS standards at minimum, and for demanding applications, MIL-grade testing is a strong signal of durability. TEJTE’s SMA line is validated for consistent electrical performance, making them suitable for network communication boards, RF measurement instruments, and even medical devices.

Performance figures speak louder than claims. For instance, TEJTE’s SMA-KWE right-angle jacks deliver ≤0.15 dB insertion loss at 6 GHz and endure ≥5000 mating cycles, ensuring they remain stable even after heavy use.

Related insight: the RF connector selection guide explains how connector quality directly influences overall system stability.

Verifying materials and manufacturing process

Brass with gold plating – balances conductivity and resistance to corrosion.
Stainless steel housings – ideal for outdoor or aerospace use, offering higher tensile strength.
PTFE dielectric – ensures stability across wide temperature ranges (-65°C to +165°C).

For antenna systems exposed to the elements, using an sma waterproof connector is essential. TEJTE’s IP67-rated designs include silicone rubber seals and gold-plated contacts, tested to withstand 1000V rms and maintain ≥5000 MΩ insulation resistance. Without these protections, even a small amount of moisture can degrade performance quickly.

How do I order SMA connectors from TEJTE?

Once you’ve identified the correct sma connectors for your project, placing an order with TEJTE is straightforward. Whether you’re sourcing small batches for prototyping or large runs for production, the process is designed to balance flexibility with efficiency.

Choosing the connector type, length, and custom requirements

Pick the connector version you need: male, female, jack, or plug.
Decide on orientation—straight or a sma right angle connector, depending on your layout.
Match the connector to your coaxial type: RG316 or RG174 sma coaxial cable assemblies are common for compact wireless projects, while LMR-series works best for outdoor installations.
For board-level designs, consider sma pcb connectors with through-hole or surface-mount options.
Customization is available: tooth length, plating finish (gold, nickel, silver), logo engraving, and even small-batch runs for specialized antenna systems.

Lead time and after-sales support

Quotation – provided quickly once connector type and cable requirements are confirmed.
Lead time – typically 7–15 days, depending on order size and customization.
Prototype sampling – available for validation before mass production.
After-sales service – includes technical support and replacement if any manufacturing defects are found.

To streamline your process, you can order SMA connectors for custom solutions directly, or explore SMA coaxial cable assemblies suited for high-frequency performance.

FAQ

What is the difference between SMA male and SMA female connectors?

An sma male connector has a center pin with external threads, while the sma female connector includes a center socket with inner threads. They fit together to form a secure RF connection. For a detailed explanation, you can read TEJTE’s guide on SMA connector male vs female types.

How do I choose the right SMA connector for my antenna system?

First, confirm whether your antenna uses an SMA female or RP-SMA female port. Then match it with the correct sma male connector or RP-SMA male cable. Pay attention to impedance—most antennas require 50Ω—and, for outdoor setups, always select an sma waterproof connector with IP67 sealing. For more context, the WiFi antenna guide explains connector choices across 433 MHz, 4G, and 5G systems.

What are the common mistakes when selecting SMA connectors for RF applications?

The most frequent errors include mixing 50Ω and 75Ω SMA connectors, confusing RP-SMA with standard SMA, and overlooking environmental requirements. Using a standard indoor connector outdoors, without sealing, often leads to corrosion. TEJTE’s sma waterproof connectors are built to prevent this issue.

How do I crimp an SMA connector correctly?

When working with an sma crimp connector, use the correct stripping dimensions and a ratcheted crimp tool. For RG316 cable, the inner conductor strip length is around 3.0 mm, with ferrule crimp depth of 2.5–3.0 mm. After crimping, check visually that no braid is loose and confirm continuity with a multimeter. More detail is available in TEJTE’s sma adapter assembly guide.

What materials should I consider when purchasing SMA connectors for outdoor use?

For outdoor or industrial projects, connectors built with stainless steel housings and gold-plated brass contacts last longer. Pairing them with PTFE dielectric ensures stable performance from -65°C to +165°C. TEJTE’s sma waterproof connector range includes IP67-rated designs with silicone seals for weather resistance.

Can I use a right-angle SMA connector for tight spaces?

Yes. A sma right angle connector is ideal when space is limited or when cables need to be routed sideways from a PCB. TEJTE’s SMA-KWE right-angle jacks, for example, are tested at ≤0.15 dB insertion loss @ 6 GHz, providing stable performance even in compact enclosures. For deeper insights, see SMA right-angle options.

How do I verify the quality of SMA connectors before purchasing?

Check for certifications such as RoHS, review VSWR and insertion loss data, and confirm the plating thickness. A reliable sma coaxial cable assembly should specify frequency range (e.g., DC–6 GHz) and mechanical durability (≥500 cycles). TEJTE provides RF connector specs that highlight these performance benchmarks.

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