TNC female to female RF Coax Connector

TNC Female to Female RF Coax Connector, commonly known as a TNC barrel adapter or coupler, is a simple yet essential component in radio frequency (RF) coaxial systems. This type of adapter is designed to connect two TNC male plugs together, effectively extending the length of an existing TNC coaxial cable or changing the gender of a TNC male-ended cable to a female connection. It features TNC female jacks on both ends, each characterized by an outer-threaded body and a central receptacle, ready to receive the center pin and inner threads of a TNC male plug.

Utilizing the secure threaded coupling mechanism inherent to TNC connectors, this adapter ensures a robust and vibration-resistant connection, crucial for maintaining signal integrity in demanding environments. It is meticulously engineered to preserve the standard 50 Ohm impedance of TNC systems across its connection, minimizing signal loss and reflections. This makes it ideal for applications requiring a direct, in-line extension of TNC cabling, such as in networking, telecommunications, wireless communication systems, and test and measurement setups, where reliable and consistent RF signal transmission is paramount.

Technical Specification

1. Electrical Characteristics:

Impedance: 50 Ω (Ohms). This is the standard impedance for TNC connectors and this adapter is designed to maintain it for optimal signal transfer and minimal reflection when connecting 50 Ohm TNC male cables.
Frequency Range: Typically DC to 6 GHz, with high-performance versions extending up to 11 GHz or even 18 GHz. Being a straight adapter, it generally offers excellent broadband performance within the TNC series’ capabilities.
VSWR (Voltage Standing Wave Ratio): A measure of how well the impedance is matched, indicating reflected power. For a TNC Female to Female adapter, a good VSWR is typically ≤ 1.3:1 or 1.35:1 max across its specified frequency range. Lower values are better and indicate less signal reflection. For precision adapters, it can be as low as ≤ 1.2:1 at 18 GHz.
Insertion Loss: Represents the signal power lost as it passes through the connector. For a high-quality TNC Female to Female adapter, this is very low, often around ≤ 0.1 dB to 0.2 dB max at the upper end of its frequency range (e.g., 6 GHz or 11 GHz).
Working Voltage: Typically 500 V RMS (Root Mean Square) at sea level.
Dielectric Withstanding Voltage: The maximum voltage the insulator can withstand without breaking down, usually around 1500 V RMS at sea level.
Insulation Resistance: A measure of the resistance of the insulator, typically ≥ 5000 MΩ (Megohms) min.
Contact Resistance: Very low for efficient signal transfer.
- Center Contact: ≤ 1.5 mΩ (Milliohms) max
- Outer Contact: ≤ 0.2 mΩ to 3.0 mΩ max

2. Mechanical Characteristics:

Coupling Mechanism: Threaded (7/16-28 UNEF thread). This provides a highly secure connection that is resistant to vibration and accidental disconnection.
Connector Interface: TNC Female on both ends (outer-threaded body, center receptacle).
Mating Cycles (Durability): The number of times the connector can be mated and unmated without significant degradation in performance, typically ≥ 500 cycles.
Coupling Nut Retention: The force required to pull the coupling nut off the connector body, usually around 100 lbs (444.8 N) min.
Body Style: Straight adapter (unless specified as a bulkhead or right-angle variant).

3. Material Specifications:

Body/Shell: Typically brass, with durable plating such as nickel or passivated stainless steel for excellent corrosion resistance and mechanical strength.
Center Contact: Beryllium copper or brass, commonly with gold plating for superior conductivity and resistance to oxidation.
Insulator/Dielectric: PTFE (Polytetrafluoroethylene, commonly known as Teflon) is the preferred material due to its excellent electrical properties, low dielectric constant, and temperature stability.
Gasket/Seal (if applicable for weatherproof versions): Silicone rubber.

4. Environmental Characteristics:

Operating Temperature Range: A wide range is typical, often from -55°C to +85°C, or for high-performance/military-grade versions, -65°C to +165°C.
Vibration: Designed to withstand significant vibration, often tested according to standards like MIL-STD-202, Method 204.
Shock: Resistant to mechanical shock (e.g., MIL-STD-202, Method 213).
Corrosion Resistance: Good resistance to corrosion, often demonstrated by salt spray testing (e.g., MIL-STD-202, Method 101).
Moisture Resistance: Capable of withstanding humid or wet conditions (e.g., MIL-STD-202, Method 106).