Cable
RG400
End A
PL259 UHF Male
End B
TNC FEMALE
Specs Summary
6 ft RG400 — PL259 UHF Male to TNC FEMALE
RG400 cable assembly, 6 feet, with PL259 UHF Male and TNC FEMALE connectors. Hand-assembled, tested, and ships free within the US.
6 ft — PL259 UHF Male / TNC FEMALE
$33.98
Free shipping • In stock
Other lengths:
Signal Loss — 6 ft
Approximate insertion loss for this 6 ft RG400 assembly at common RF frequencies.
| Frequency | Loss / 100 ft | Loss — 6 ft |
|---|---|---|
| 100 MHz | 3.5 dB | 0.21 dB |
| 450 MHz | 7.8 dB | 0.47 dB |
| 900 MHz | 11.5 dB | 0.69 dB |
| 1.8 GHz | 17 dB | 1.02 dB |
| 2.4 GHz | 20 dB | 1.2 dB |
| 5.8 GHz | 34 dB | 2.04 dB |
About This Assembly
RG400 Cable
RG-400 is a double-shielded, silver-plated PTFE coaxial cable built to MIL-C-17 specifications with a 0.195" outer diameter. Its construction mirrors RG-142 but with two braid shields for even greater shielding effectiveness. The standard cable for military and avionics applications requiring certified materials and traceable performance.
UHF Connector
The UHF connector (also known as PL-259 male / SO-239 female) is a large, low-cost RF connector designed in the 1930s for HF and VHF frequencies. Despite its name, its practical usable range is below 300 MHz due to its non-constant impedance design. It remains extremely popular in amateur radio (HF through VHF), CB radio, and marine radio applications.
TNC Connector
TNC (Threaded Neill–Concelman) is the threaded version of BNC, offering improved performance up to 11 GHz and better vibration resistance through its screw coupling. It is commonly used in mobile radio antennas, avionics, and outdoor installations where BNC's bayonet lock would not provide sufficient mechanical security.
Common Applications
This TNC and UHF cable assembly is well suited for military-spec RF interconnects and avionics signal routing. The combination of reliable TNC and UHF connectors and custom-cut cable length makes it a practical choice for both field installations and bench setups. Every assembly is hand-terminated, continuity tested, and ships free within the USA.
Frequently Asked Questions
Is this cable hand-assembled in the USA?
Yes. Every CoaxRF cable assembly is hand-terminated and continuity tested at our US facility before shipping. We do not drop-ship pre-made cables from overseas — each cable is built to order.
Can I order a different length than 6 ft?
Yes. This page is for the 6 ft assembly. Use the length buttons above to select a different standard length, or use the Cable Builder for any custom length.
How much signal loss will I see with this 6 ft cable?
At 1800 MHz, RG400 loses approximately 17 dB per 100 ft. This 6 ft assembly will have roughly 1.02 dB of insertion loss at that frequency. See the signal loss table for all frequency points.
What is the maximum frequency for this assembly?
This assembly is rated DC – 300 MHz. The effective frequency limit is set by the lowest-rated component — either the cable or one of the connectors. Both PL259 UHF Male and TNC FEMALE connectors must be within spec at your target frequency.
What is your return policy?
We accept returns within 30 days of delivery. Custom-length cables are accepted as long as they are in original condition. Contact us and we will provide a prepaid return label at no charge.
