Checking a Coaxial Cable for Damage with a Multimeter – Part II

September 11, 2019 Michael Traskos

In the last article, Lectromec introduced a damaged coaxial cable and tried three techniques to distinguish it from an undamaged cable. The standard multimeter tests (capacitance, inductance, and resistance measurements) found no appreciable difference.

The idea of this evaluation was to demonstrate that the classic multimeter, while a great tool, is not suitable for detecting damage to coaxial cables.

But we cannot run an article and leave it without a solution. In this article, we continue the testing of a damaged coax cable to see what technology, if any, can identify and perhaps locate the damaged section of cable.

Checking a Coaxial Cable for Damage with a Multimeter

August 23, 2019 Michael Traskos

The electronic multimeter is a great tool; invented in the 1920s, the multimeter has been used by millions of technicians and engineers seeking to measure circuits and troubleshoot electrical issues. So common are these tools now that it is almost impossible to consider a toolbox complete without one.

While these are great tools and can be employed in a million situations, they are not the magic tool that can diagnose every circuit. If only one thing is remembered from this article: multimeters are not the tool to use for coaxial cables

Use of MIL-T-81490 cable in place of a MIL-DTL-17 cable

December 20, 2018 Michael Traskos

A common ‘go-to’ cable for RF applications is the MIL-DTL-17 cable. Many of the MIL-DTL-17 cables are rated to 1 GHz, some to 12.4 GHz (like M17/128), and only a couple at 20GHz (e.g. M17/130 and M17/133 – a word of caution with the /130 and /133 constructions: these are unjacketed cables with an exposed external conductor/shield). There is the M17/205 construction that is spec’d for up to 50GHz, but that comes with a caveat: attenuation. The accompanying figure shows the attenuation per 100ft of M17/205 cable; while the attenuation does rise quickly with higher frequencies, the specification does not provide any attenuation limits beyond 10 GHz. Read more

Understanding Coaxial Cables

October 4, 2016 Michael Traskos

The development and use of coaxial cables have come a long way since its invention in 1880. Improvements in design and reliability have made it a frequent feature for aircraft data transmission applications. In the realm of aerospace, a common coaxial specification is the MIL-DTL-17 coaxial cable standard. There are several parts to the MIL-DTL-17 […] Read more

Coaxial cable