Inside Frequency Control

Frequency perturbations, also referred to as activity dips, can be difficult to spot in crystal oscillators. But a single perturbation can cause major problems in an application’s signal, including within GPS or missile systems.

Imagine launching a missile and then losing control of its navigation. Or getting a very inaccurate GPS velocity reading of an aircraft. These (and many other problems) can be caused by a failure to spot activity dips in crystals.

In this article, we'll help you  understand what frequency perturbations are and how to prevent them from occurring in crystal oscillators.

These are exciting times to be working in any field of engineering, but especially in the radio frequency (RF) industry. The modern economy simply cannot function without RF technology, and as we transition into a world of ever-faster mobile service, civilian and military space-based systems, and the Internet of Things (IoT), we’ll  rely increasingly on microwave, low-frequency engineering.

With all the rapid change in the industry and advancements in RF tech, it’s going to be more important than ever to find a crystal oscillator manufacturer that follows the best practices that have guided RF engineers in the past and will continue to in the future.

In this article, we'll provide a basic overview of the RF technology best practices your crystal oscillator manufacturer should be following.

Quartz crystal oscillators are the high and mighty option for low phase noise and added frequency stability in circuit design. Yes, simple oscillators like those made with resistor-capacitor (RC) or inductor-capacitor (IC) resonators are fine for some circuits.

But if you're dealing with higher performance applications in the aerospace, military, and space industries, you're going to want a higher performance crystal oscillator that can maintain low phase noise and strong stability. Otherwise, you'll risk deviating from the very specific (and usually critical) center frequency selected for your design.

In this blog, we'll discuss how to measure low phase noise and how to maintain it in your applications.

One is definitely the loneliest number. So what's better, a single (OCXO) or double oven controlled crystal oscillator (DOCXO)?

One of the core challenges any RF engineer faces is maintaining frequency stability in crystal oscillators. In an ideal world, an oscillator would transmit at the desired frequency indefinitely and without deviation… but of course, we don’t live in an ideal world, and frequency drift is a real problem in many applications.

There are a number of factors that can cause an oscillator to deviate from the correct frequency, but frequency drift is not an insurmountable issue. There are various approaches engineers can take to improve stability. In this article, we'll discuss the best approaches to maintaining a high degree of stability your in crystal oscillators.

Will a crystal oscillator operate outside its specified temperature range? This is a common question and the short answer is: yes, but it's complicated.

If, for example, a crystal oscillator is specified over 0 to 60 °C, it will most likely perform without any issues over -40 to 85 °C. But it's possible that it will fall outside its specified stability. This may not matter if the application needs just a stable frequency rather than an accurate frequency.

RF engineers would love to get their hands on an ideal crystal oscillator circuit. That is, a quartz crystal oscillator that transmits at the designated frequency for the entire life of the device without any frequency deviation. Unfortunately, that ideal circuit world is a mathematical fantasy.

There are many factors that contribute to quartz oscillator stability and frequency drift issues. To prevent these problems as much as possible, it's important to have a firm understanding of precise frequency stability. This will give you the tools to keep your applications performing optimally. But there's another problem...

Poor manufacturing environments can significantly reduce the performance quality of a pressure transducer. A failing pressure transducer will lead to problems with sensors and will provide inaccurate readings (or none at all).

A faulty pressure transducer can not only cause frustration and waste time, but it can also lead to unnecessary costs.

To prevent pressure transducer problems or failure from happening in the first place, let's take a look at seven pressure transducer troubleshooting methods to keep your transducers and sensors working great!

There are many different types of crystal oscillators. OCXOs, TCXOs, and VCXOs are some of the most common types of oscillators. Each have their own advantages and disadvantages. One of the core responsibilities of a lead RF engineer is to pick the oscillators that are an optimal fit for their designs and applications.

If you want to be able to fine-tune your frequency source and get a stable, dependable signal, a voltage-controlled crystal oscillator (VCXO) might be just the solution you’re looking for. Let’s explore the benefits of the VCXO and how you can put them to work in your designs.

Do you know all about atomic clocks in space and how they work? If not, it's about TIME you do. (Haha. Ha. Ha...)

Timing is everything when it comes to GPS satellites and other space applications. Even just a one-microsecond error in timing can lead to an error of 300 meters on the ground. Because atomic clocks can maintain very precise timing, they're a great solution for GPS and other LEO satellites.