LMR-240 Cable Loss Calculator

This tool computes the attenuation loss of a user-specified length of LMR-240 RF coaxial cable [1]. This is a popular antenna cable.

To use the insertion loss calculator use the tool below. Enter

  • Cable length and the units (feet/inches/meters)
  • Frequency of operation in MHz




LMR cables are made by Times Microwave. They come in different varieties differentiated by a numerical suffix. For instance, LMR200, LMR 400, LMR 600 – each with different electrical attributes. The frequency of operation can be as high as 8 GHz making them suitable for everything from HF to Wi-Fi 6e.

The cable has an outer conductor (shield) and an inner conductor (coaxial cable), which are separated by a dielectric material. The cable also has a Jacket (outer cover) that protects the inner conductors from environmental damage.

What does LMR stand for?

LMR stands for Land Mobile Radio. Typical LMR frequencies are in the VHF and UHF (30 MHz to 512 MHz) range. However LMR cables can be used for frequencies up to 8 GHz.


[1] Coaxial Cable on Wikipedia

[2] LMR 240 data sheet from Times Microwave