# Author: James Wren

## How Do I Upsample and Downsample My Data?

This post covers how to upsample and downsample data and the possible pitfalls of this process. Before we cover the technical details let us first explain what we mean

## What Are Vibration, Torsional Vibration & Shaft Twist?

When analyzing rotating shafts some terms are often confused. This post will attempt to explain the differences. So, what are vibration, torsional vibration and twist? What is Vibration? We

## The Effect of the Nyquist Theory on Rotational Order Analysis

Nyquist theory is generally understood, but this understanding usually relates to time sampling and the conversion to the frequency domain. Rotational order analysis and the effect of the

## How to avoid a ground loop – It’s not only a problem with accelerometers

When using modern, high technology measurement devices one can often be tripped up by the simplest things. The most common is the ground loop. Time and again this

## Speech Articulation Index – What Does It Mean?

There are many ways to calculate speech articulation index and each has its advantages in different applications. Prosig’s DATS includes four methods for evaluating the Articulation Index as seen in

## Processing pump data – a classic case of amplitude modulation

When dealing with some vibration data from a pump, we observed some strange phenomena in the data. It turned out to be a classic case of amplitude modulation.

## How do we design or modify a system to avoid resonance?

After finding the natural frequency of a system, what could be done to stop or reduce the systems resonance being excited? Basically put, how do we avoid resonance

## Three Methods For Analyzing Vibration In Rotating Components

In this post we will first look at how to process data from rotating machinery. Then we will focus on shaft or gear train twist. Let’s look at

## What Is Resonance? (Part 3)

In the previous two articles (What Is Resonance? (Part 1) & What Is Resonance (Part 2)) in this series we have looked at how we can identify a

## What Are AC and DC Coupling?

This is an important subject to understand when working in the signal processing field. In terms of AC and DC Coupling, what is Coupling? Quite simply, coupling is

## Video: How To Calibrate Microphones & Accelerometers

Here are two videos on a relatively simple, but sometimes misunderstood procedure – how to calibrate microphones & accelerometers

## Understanding Filter Characteristics

Recently when discussing with an engineering student the characteristics of filters, it became clear that some confusion exists around this subject area. This note attempts to explain the differences

## A Simple Capture, Analysis and Report (Part 4)

This is the final part of our four part tutorial. This adds a report to the worksheet we developed in part 3.

## A Simple Capture, Analysis and Report (Part 3)

Today we have the third of our four part tutorial. Here we show how to quickly build a worksheet to analyze the data we captured in parts one

## A Simple Capture, Analysis and Report (Part 2)

Part two of the four tutorials showing a simple setup to capture, analyze and produce a report using Prosig’s DATS software and P8000 hardware. This part deals with

## A Simple Capture, Analysis and Report (Part 1)

The first part of a series of four tutorials showing a simple setup to capture, analyze and produce a report using Prosig’s DATS software and P8000 hardware. Part

## What Is The Difference Between Single Ended & Differential Inputs?

Prosig P8000 systems use differential inputs, but what are they and why are they so special? This subject is not always fully understood and, therefore, the focus of

## Converting Acceleration, Velocity & Displacement

From time to time I meet engineers who are interested in the conversions between acceleration, velocity and displacement. Often, they have measured acceleration, but are interested in displacement

## How To Float Output Windows in DATS Acquisition V4

Nowadays it is easy to attach extra screens to most computers. It is not uncommon to have a two or even three monitor setups. Even with laptops it

## Comparison Between Sound Intensity Probes and Acoustic Cameras

Sometimes we are asked about the differences between an acoustic camera and a sound intensity probe and which of the two is better for a particular application. There

## What is the difference between microphone types?

I’m often asked what is the difference between free field microphones, diffuse field microphones and pressure microphones. For a run-of-the-mill ½ inch microphone the short answer is nothing.

## A Simple Frequency Response Function

The following article will attempt to explain the basic theory of the frequency response function. This basic theory will then be used to calculate the frequency response function