RG400 coaxial cable layers


Attenuation @ 1000 MHz

0.48 dB/m


50 Ω

Inner Conductor

Silver Plated Copper

Dielectric Material

Outer Conductor

Silver Plated Copper Braid (1)
Silver Plated Copper Braid (2)


RG-400 is a high temperature coaxial cable used in interconnections between telecommunications equipment and is widely used for commercial wireless applications such as avionics, radar, GPS, and medical systems. Featuring a PTFE dielectric and FEP jacket the cable is rated for operation up to 200°C. The cable's 4.95 mm overall diameter makes it suitable for applications with limited space. The cable differs from the more popular RG-142 only by its stranded conductor.

Shielding effectiveness of RG-400 is typically >80 dB to 6 GHz and >60 dB to its cutoff frequency of 12.4 GHz making it ideal for a range of microwave band applications.

Typical Electrical Specifications Typical Mechanical Specifications
Operating frequency range DC to 12.4 GHz Inner conductor (mm) 19 x 0.203
Capacitance (pF/m) 105 Dielectric (mm) 2.95
Velocity of propagation (%) 70 Outer conductor (mm) 3.95
Shielding effectiveness (dB) >60 Jacket (mm) 4.95
Maximum operating voltage (KVrms) 1.4 Operating temperature -55 to +200 °C