What Is LMR-400?

LMR cable is a low-loss coaxial cable. The primary feature of this cable is its low losses, especially at high frequencies. LMR400 50-ohm coaxial cable is relatively heavy, with an outside diameter of 0.4 inches. While flexible, it has a maximum recommended bend radius of 1 inch in fixed installations and 4 inches when the cable is unsecured. LMR is a registered trademark of Times Microwave Systems, which manufactures LMR series coaxial cables.

7 items

  • Times Microwave
    LMR-400
    $0.00 / 1000 FT
    • Application: Outdoor
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • Times Microwave
    LMR-400 DB
    $0.00 / 1000 FT
    • Application: Outdoor/Watertight
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • Times Microwave
    LMR-400-FR
    $0.00 / 1000 FT
    • Application: Indoor/Outdoor Riser CMR
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • Times Microwave
    LMR-400-FR-PVC
    $0.00 /
    • Application: Indoor/Outdoor Riser CMR
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • Times Microwave
    LMR-400-LSZH
    $0.00 / 1000 FT
    • Application: Low Smoke Zero Halogen
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • Times Microwave
    LMR-400-PVC
    $0.00 / 1000 FT
    • Application: General Purpose
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    View Details
  • $0.00 / 1000 FT
    • Application: General Purpose
    • Approx LBS/MFT: 68.00
    • Cond. Material: Bare Copper Clad Aluminum
    Order
    Add to List

Characteristics of LMR-400 Cable

LMR-400 has an ultraviolet-resistant polyethylene outer jacket with a service life of up to 20 years outdoors. The cable uses foam polyethylene dielectric. It has a double shield that provides greater than 90 decibels of radio frequency (RF) shielding, comparable with the shielding achievable with semi-rigid coaxial cabling. You can use this cable for communications frequencies up to 5.8 GHz and losses at that frequency are 10.8 dB per 100 feet. Different versions include waterproof cable, non-halogen (no smoke) variants, and one with a low-cost PVC outer jacket.

LMR-400 Cable Construction

Conductor

Times Microwave LMR-400 has a solid bare copper clad aluminum (BCCAl) conductor with a diameter of 0.108 inches.

Dielectric Insulation

These low loss coax cables use a foamed polyethylene dielectric with a nominal outer diameter of 0.285 inches.

Shield

The cable has a dual shield. The inner shield, which acts as the return conductor, is aluminum tape. A tinned copper outer braid protects the aluminum tape and improves shielding.

Jacket

The standard jacket is a UV-resistant polyethylene jacket with a rated outdoor life of 20 years. Waterproof versions incorporate a sealing compound under the jacket. You can specify a PVC jacket and flame-resistant jackets.

LMR-400 Applications

This low loss cable cable is a direct replacement for RG8 coaxial cable. It's used for direct wireless transmission and as antenna feeds in the 5.8 GHz band including GPS, wireless local area network (WLAN), wireless internet, and microwave communications.

Comparison Between Lmr-400 Coaxial and Other Popular Coaxial Cables

  LMR-400 RG8 RG58 RG213 LMR-900
Impedance ohms 50 52 53.5 50 50
Attenuation 900MHz
(dB/ft)
3.9 4.1 13.0 8.2 1.7
Attenuation 5.8 GHz 10.8 40.9 51.6 28.6 4.9
Maximum Voltage (DC) 2500 4000 4000 2500 5000
Diameter (in) 0.405 0.405 0.405 0.405 0.870

LMR-400 Coaxial Cable Specifications

Central Conductor: Solid bare copper clad aluminum
Dielectric: Polyethylene foam
Outer Conductor and Shield: Aluminum Tape
Outer Shield: Tinned copper braid
Jacket: Black polyethylene (waterproof, nonsmoking, and PVC alternatives)
Nominal Impedance: 50 ohms
Nominal Capacitance: 23.9 pf/ft
Operating Temperature Range: -40°C to 85°C
Maximum Voltage: 2500V (DC)
Conductor Resistance: Inner Conductor: 1.39 ohms/1000ft
Outer Conductor: 1.65 ohms/1000ft
Velocity of Propagation: 85%
Attenuation at 900 MHz: 3.9 dB/100ft
Shielding Effectiveness: >90 dB

Contact us to learn more about using Times Microwave LMR coaxial cables.