RG400 cable

Cable

RG400

PL259 UHF Male

End A

PL259 UHF Male

SMA MALE

End B

SMA MALE

Specs Summary

CableRG400
Diameter.195 INCH
Impedance50 Ohm
FrequencyDC – 300 MHz
Length50 ft
Velocity Factor70%
PL259 UHF Male InterfaceUHF threaded (PL-259 / SO-239)
SMA MALE InterfaceSMA threaded (MIL-STD-348)
50 Ohm DC – 300 MHz

50 ft RG400 — PL259 UHF Male to SMA MALE

RG400 cable assembly, 50 feet, with PL259 UHF Male and SMA MALE connectors. Hand-assembled, tested, and ships free within the US.

50 ft — PL259 UHF Male / SMA MALE

$150.38

Free shipping • In stock

Need a different length? Use the Cable Builder

Signal Loss — 50 ft

Approximate insertion loss for this 50 ft RG400 assembly at common RF frequencies.

Frequency Loss / 100 ft Loss — 50 ft
100 MHz 3.5 dB 1.75 dB
450 MHz 7.8 dB 3.9 dB
900 MHz 11.5 dB 5.75 dB
1.8 GHz 17 dB 8.5 dB
2.4 GHz 20 dB 10 dB
5.8 GHz 34 dB 17 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.

SMA Connector

SMA (SubMiniature version A) is the most widely used RF connector in the industry, offering a threaded interface that provides a secure, low-reflection connection from DC to 18 GHz. Its compact size, 50-ohm impedance, and broad frequency range make it the default choice for WiFi equipment, software-defined radios, cellular antennas, GPS receivers, and RF test instruments.

Common Applications

This SMA and UHF cable assembly is well suited for military-spec RF interconnects and avionics signal routing. The combination of reliable SMA 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 50 ft?

Yes. This page is for the 50 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 50 ft cable?

At 1800 MHz, RG400 loses approximately 17 dB per 100 ft. This 50 ft assembly will have roughly 8.5 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 SMA MALE 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.

Other RG400 Configurations