TNC Connector
Understanding the TNC Connector
The TNC connector was developed in the 1950s-60s as a threaded improvement to the bayonet-style BNC. The threaded coupling provides consistent contact pressure and eliminates the accidental disconnection that plagues BNC in high-vibration environments.
Key Specifications
- Impedance: 50 ohms (standard), 75 ohms (video/CATV variant)
- Frequency range: DC to 11 GHz (standard), to 18 GHz with precision versions
- VSWR: 1.3:1 typical at 11 GHz
- Power handling: 100-500 W depending on frequency
- Mating cycles: 500+ per MIL-STD-348
TNC vs BNC vs SMA
- vs BNC: Same body size but threaded (not bayonet). Higher frequency (11 GHz vs 4 GHz). Better vibration resistance
- vs SMA: Larger body, higher power handling, lower max frequency. TNC for field; SMA for lab and PCB
Variants
- RP-TNC: Reverse polarity. Gender-swapped center pin. Common in Wi-Fi and WLAN equipment
- 75-ohm TNC: Matched to 75-ohm systems for video and CATV
- Configurations: Straight, right-angle, bulkhead, panel-mount. Crimp, solder, and clamp terminations
Key Equations
The TNC (Threaded Neill-Concelman) connector is a threaded variant of the BNC providing reliable RF connections from DC to 11 GHz. Its threaded coupling mechanism...
Key specifications:
11 GHz | 50 ohm | 75 ohm | 18 GHz
Power: P(dBm) = 10log(PmW), 0dBm = 1mW
Comparison
| Connector | Freq Max | Impedance | Power | Interface |
|---|---|---|---|---|
| SMA | 18 GHz | 50 Ω | 0.5 W | Threaded |
| N-Type | 11 GHz | 50 Ω | 5 W | Threaded |
| 2.92mm (K) | 40 GHz | 50 Ω | 0.3 W | Threaded |
| 1.85mm (V) | 67 GHz | 50 Ω | 0.2 W | Threaded |
| 1.0mm (W) | 110 GHz | 50 Ω | 0.1 W | Threaded |
Frequently Asked Questions
What is a TNC connector?
TNC (Threaded Neill-Concelman) is a threaded version of the BNC connector rated DC to 11 GHz. The threaded coupling provides vibration-resistant connections for military, telecom, and aerospace applications. 50-ohm impedance, MIL-STD-348 compliant.
How does TNC compare to BNC and SMA?
TNC offers higher frequency than BNC (11 GHz vs 4 GHz) due to threaded coupling. SMA is smaller and works to 18+ GHz but handles less power. TNC is preferred when vibration resistance and moderate power handling are needed.
What are TNC connector variants?
Standard 50-ohm TNC, Reverse-Polarity TNC (RP-TNC) for Wi-Fi, and 75-ohm TNC for video. Available in straight, right-angle, bulkhead, and panel-mount with crimp, solder, or clamp terminations.