N-Type RF Connector: The Outdoor Standard for VHF, UHF, and Cellular

If you're installing an outdoor antenna — for a ham repeater, a cellular booster, a commercial WiFi bridge, or a VHF/UHF base station — N-type connectors belong on every connection in that signal path. N-type has been the outdoor RF standard since the 1940s, and for good reason: it's threaded, weatherproof, handles significant power, and performs cleanly from DC to 11 GHz. Here's everything you need to know about using it correctly.

What N-Type Is

N-type was developed by Paul Neill at Bell Telephone Laboratories in the 1940s, hence the "N" designation. It's a precision-machined threaded connector with a 7/16-inch hex coupling nut. The mating interface is dimensionally controlled to maintain a consistent 50-ohm impedance from DC to 11 GHz. When properly torqued (15 in-lbs) and sealed, a mated N-type pair is IP67 rated — submersible to 1 meter.

The connector family has been standardized in MIL-C-39012, IEC 60169-16, and multiple other military and civilian specifications, which means an N-type connector from any reputable manufacturer will mate reliably with N-type connectors from any other manufacturer. This standardization and the electrical precision of the connector are why it became the outdoor professional standard.

N-Type Specifications

Why N-Type for Outdoor Use

Threading prevents vibration loss. BNC bayonet connections can loosen from wind-induced cable movement and thermal expansion over months of outdoor use. N-type's thread engagement maintains a reliable connection regardless of vibration or movement.

Better VHF/UHF performance than PL-259. PL-259 (the SO-239 socket used on most HF transceivers) has no controlled electrical geometry above about 300 MHz. At 144 MHz it introduces measurable insertion loss and reflections. At 440 MHz it's worse. N-type is precision-controlled to 11 GHz and introduces essentially no additional loss beyond the connector's contact resistance.

Higher power handling than SMA or TNC. SMA handles approximately 100W at 1 GHz. TNC handles about 150W. N-type handles 500W. For repeater installations, high-power amplifiers, and commercial base stations, N-type is the only connector with adequate power handling.

Equipment with N-Type Ports

Ubiquiti Rocket M2, M5, AC, and PowerBeam access points all use N-type. Cambium PMP 450 and ePMP series use N-type. Outdoor yagi antennas, sector antennas, and omnidirectional base station antennas from any professional manufacturer use N-type. WeBoost (Wilson Electronics), SureCall, and Cel-Fi cellular signal boosters use N-female ports on the booster unit and N-type outdoor antennas. PolyPhaser and similar lightning arrestors use N-female pass-through configuration. Amateur radio repeater antennas from Hustler, Diamond, and others use N-type.

N vs PL-259: Know When to Stop Using PL-259

PL-259 is entirely appropriate for HF operation (below 30 MHz) at the transceiver and tuner connections in your shack. It should not be used outdoors at VHF/UHF frequencies. At 144 MHz, an N-type connection has about 0.05 dB of insertion loss; a PL-259 connection has approximately 0.15–0.3 dB, and the variance is large because the geometry isn't controlled. At 440 MHz the difference is greater. For a repeater that operates around the clock and needs every fraction of a dB of receive sensitivity, N-type throughout is not optional.

N vs TNC: Similar Performance, Different Applications

TNC (Threaded Neill-Concelman) is essentially a smaller version of N-type. It uses the same threaded coupling concept, achieves similar frequency performance (DC to 11 GHz), and has comparable weatherproofing. The key differences: TNC has a smaller body diameter (~14mm vs ~21mm) and lower power handling (about 150W vs 500W for N). TNC is used on military handheld equipment, smaller-form-factor antennas, and applications where space is at a premium. For full-size outdoor antennas and repeater feedlines, N-type's power handling and larger weather seal make it the better choice.

N to PL-259: Connecting Outdoor Antennas to HF/VHF Transceivers

Many transceivers — including popular all-band rigs like the Icom IC-7300, IC-9700, and Yaesu FT-991 — use PL-259 (SO-239) for all their antenna ports. When connecting an N-type outdoor antenna (VHF/UHF yagi, repeater antenna, base station vertical) to these radios, you need an N-to-PL-259 cable. Use LMR-400 or RFC400 for any run over 10 feet.

LMR-400 N-Male to PL-259  |  RFC400 N-Male to PL-259  |  LMR-600 N-Male to PL-259

N to SMA: Antennas to SDR and Measurement Equipment

SDR receivers, GPS modules, and bench instruments commonly have SMA ports. When connecting an N-type outdoor antenna to this type of equipment, use a flexible, low-loss cable. RFC195 is ideal for shorter runs inside a rack or equipment bay.

RG58 N-Male to SMA  |  RFC195 N-Male to SMA  |  RFC400 N-Male to SMA

N to RP-SMA: Outdoor Antennas to WiFi Equipment

Consumer and prosumer WiFi equipment uses RP-SMA. Outdoor yagi and panel antennas use N-type. An N-to-RP-SMA cable bridges these two worlds, commonly used when mounting a directional WiFi antenna on a roof or mast and routing the cable to a router or access point inside. Use RFC195 for runs up to 20 feet; use RFC400 or LMR-400 for longer outdoor-to-indoor runs.

RFC195 N-Male to RP-SMA  |  RFC400 N-Male to RP-SMA  |  LMR-400 N-Male to RP-SMA

N to TNC: Repeater and Military Connections

Duplexers and some commercial repeater components use TNC ports. Connecting an N-type feedline to a TNC-ported duplexer requires an N-to-TNC jumper. Use the shortest practical cable for this connection — every connection in the receive path adds noise figure.

RFC195 N-Male to TNC  |  RFC400 N-Male to TNC  |  LMR-400 N-Male to TNC

N-Male to N-Male Jumpers

N-to-N jumper cables are used between a duplexer and an amplifier, between a lightning arrestor and a patch panel, and on test benches characterizing N-type components. Use LMR-400 or RFC400 for any jumper carrying transmit power; use RFC195 for receive-only signal paths where flexibility matters more than low loss.

RFC195 N-Male to N-Male  |  RFC400 N-Male to N-Male  |  LMR-400 N-Male to N-Male  |  LMR-600 N-Male to N-Male

Torque and Field Installation Note

The specified torque for N-type is 15 in-lbs. In field installations without a torque wrench, finger-tight plus approximately a quarter turn with a 7/16-inch wrench achieves roughly this value. Applying anti-oxidant compound (Noalox or equivalent) to the threads of any outdoor N-type connection prevents galvanic corrosion between dissimilar metals and makes future disassembly easier. For tower installations at height, apply thread compound before climbing — fighting a corroded N-type connector 80 feet up is an experience worth avoiding.