SO-239 female-UHF-connector

Guide to Antenna Cables & Connectors

All cables lose some signal, the amount depends on the quality of both the cable and connector.

As a general guide the thicker and less flexible the cable, the better the cable.

This is because to reduce signal loss cables often have a number of layers designed to insulate and shield the inner core from external noise.



UHF series are a variable impedance connector designed for low frequency operations 600KHz to 300MHz. This very large connector is used almost exclusively for radio and UHF applications. The low cost design of UHF connectors often results in impedance varying between 30-40Ω causing significant reflections above 300MHz. Despite this, the connector remains popular with CB/UHF (477MHz) users.

UHF Plug connector Female SO239 UHF connector
Male UHF (PL259) Connector Female UHF (SO239) Panel Mount Connector


N Type

N connectors are the 50Ω connector of choice for most high quality antenna systems due to their wide performance band – DC to 11GHz. This large sized connector has a wider diameter than most connectors but is easily tightened by hand. You will find this connector on most RF applications including radar, mobile base stations, electronic instrumentation, and of course most microwave band antennas.

n male connector cable n female connector
Male N Connector Female N Connector


This is one of the most common antenna connectors, primarily used in VHF/UHF systems. The ‘B’ in BNC refers to the Bayonet twisting interface, with the female connector featuring two bayonet lugs on either side allowing connection to be achieved with only a quarter rotation. Ideally suited to RG58/59 and subminiature cables, BNC connectors offer good performance from DC to 4GHz and have either 50Ω or 75Ω resistance. All BNC connectors on our website are 50Ω.

Male BNC Connector Female BNC Connector
Male BNC Connector Female BNC Connector
Electrical Specifications

Resistance: 50Ω
Capacitance: 96pF/m
Signal Loss: 0.79dB/m @ 850MHz, 1.27dB/m @ 2100MHz
Frequency Range: 0-3GHz
Maximum Recommended Length: 50cm (cellular bands)
Velocity of Propagation: 70%
Nominal Delay: 5.08ns/m
Voltage Withstand: 1200Volts DC

Mechanical Specifications

Weight/100m: 1.8kg
Minimum Bend Radius: 13mm
Conductor Material: Silver coated CCS (0.51mm)
Insulating Material: Teflon PTFE (1.52mm)
Outer Shield Material: Silver coated copper braid 95% Coverage (1.95mm)
Outer Jacket Material: Brown FEP (2.5mm)

Standard Cable – RG58U

RG58 cable specifications cutaway
The most common type of cable encountered. It’s likely the cable supplied with your antenna is RG58, which is flexible, has reasonable performance characteristics, and is cheap.

Super Low Loss Cable – LMR400

LMR-400 coaxial cable specifications cut-away
The highest grade antenna cable, recommended for any performance critical, industrial, and harsh environmental applications. It’s exceptional performance is achieved with a much thicker diameter (10mm) and greatly reduced flexibility (72mm minimum bend diameter). Each manufacturer of LMR400 names their cable with different letters in front of ‘400’, for example the Super Low Loss LMR400 series cable we manufacture is LCU400, ZCG Scalar’s is RU400, Benelec’s is LL400, and so on.

Electrical Specifications

Resistance: 50Ω
Capacitance: 78.4pF/m
Signal Loss: 0.12dB/m @ 850MHz, 0.20dB/m @ 2100MHz
Frequency Range: DC-16GHz
Velocity of Propagation: 85%
Nominal Delay: 3.92ns/m
Voltage Withstand: 2500Volts DC
Peak Power: 16kW

Mechanical Specifications

Weight/100m: 14.6kg
Minimum Bend Radius: 72mm
Conductor Material: Solid Copper (2.74mm)
Insulating Material: Gas Injected Foamed Polyethylene (7.24mm)
Outer Shield Material:
– (1) Sealed APA Tape 100% Coverage (7.37mm)
– (2) Tinned Copper Braid 98% Coverage (8.17mm)
Outer Jacket Material: Black Polyvinyl Chloride PVC (10.3mm)

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