Author: Steve Ferguson

MIL-STD-461 Passive Calibration

When MIL-STD-461 revision “G” was issued, I believed that the answer to many of my measurement equipment calibration issues had been solved.  Right there in the “Calibration of measuring equipment” paragraph the requirements clearly stated “After the initial calibration passive devices such as measurement system antennas, current probes, and LISNs, require no further calibration unless […]

Induced Signal Susceptibility DO-160 Section 19

The Issue: Induced signal susceptibility has been a factor in electronic equipment performance since the dawning of voltage and current.  Often referred to as crosstalk, the undesired coupling of one circuit’s signals to another may result in interference that degrades the integrity of either signal.  This article examines the testing process prescribed by RTCA DO-160 […]

Review of Bonding & Grounding Requirements

The Question What is the required bonding and grounding requirements to achieve compliance with the various electromagnetic compatibility (EMC) standards associated with electronic equipment? I received this question a few days ago and quickly realized that a quick and easy answer was not feasible since I virtually had no knowledge of  what kind of equipment […]

Review of Magnetic Effects Testing—DO-160 Section 15

The Issue From the beginning of aviation, knowledge of the aircraft direction during flight has been critical to locating destinations. The magnetic compass was used for centuries in shipping, and naturally, it was adopted for aircraft use. Without visible signposts or landmarks, direction relies on the compass to provide the necessary information. The compass aligns […]

Review of MIL-STD 1275 Requirements

Introduction This may seem disassociated from the electromagnetic compatibility (EMC) theme of this publication but issues dealing with power quality and the qualification testing has a direct link to EMC. Frequently the EMC engineers and technicians are tasked taking care of the power quality, so I believe that reviews of these standards are appropriate. MIL-STD-1275 […]

Review of Space Applications EMC Requirements

The Contract Having been a long-time manufacturer of oxygen concentrator equipment, when I saw an opportunity to bid on a job to provide an oxygen concentrator system (OCS) for a satellite project I jumped at the chance. The specifications were normal for this type of system and of course electromagnetic compatibility (EMC) requirements were included. […]

High magnetic field and RF power impact on a MRI facility

The University Hospitals Cleveland Medical Center in Cleveland, Ohio, decided in 2011 to add proton therapy to its existing radiation therapy equipment in order to provide broader services to its cancer patient population.  The Mevion S250 Proton Therapy System (PTS) was chosen for its compactness and state-of-art technology in a rotational superconducting cyclotron. Geographically, the […]

Voltage Burden

“The measurement system should not affect the measurement.” This statement is accepted throughout the test and evaluation community as a given whether it is stated in the requirements or not.  We get into the habit of taking the measurement without considering the instrument.  We expect that a voltmeter provides a very high impedance, so it […]

Review of MIL-STD-1399-300-1 Requirements

Introduction The electrical power system of a ship functions like a city’s electrical grid from the power generation to medium voltage distribution to the low voltage networks located in various sections of the ship’s structure. It only makes sense to treat the power system like a city’s power system, after all larger vessels include services […]

Review of MIL-STD 704 Requirements

Introduction This article discusses the power quality test and evaluation with a review of MIL-STD-704 and the relationship with electromagnetic compatibility (EMC). MIL-STD-704 deals with aircraft electric power characteristics, and provides the standard to ensure compatibility between the aircraft power system (including external power) and the utilization equipment. MIL-STD-704 covers the power generation system by […]