Inside Frequency Control

The most common types of crystal oscillators in electrical and RF engineering include OCXOs, TCXOs, VCXOs, and clock oscillators. In this post, we'll be reviewing the basics of temperature compensated crystal oscillators (TCXOs).

Temperature variations are the most significant factor contributing to frequency drift in crystal oscillators.

Other variables that affect frequency output, such as humidity and pressure, can be alleviated easily with a hermetically sealed packaging of the crystal in a vacuum or in an inert gas, such as nitrogen. But controlling temperature for precise frequency output in a crystal oscillator circuit requires a higher level of electronic RF design ingenuity. Enter: the oven controlled crystal oscillator (OCXO).

In this post, we'll take a look at the three types of OCXOs available for RF engineers to meet individual design priorities such as frequency precision, warm-up time, crystal aging, and power consumption.

Oscillators have become indispensable in modern technology. They are the core component that makes RF engineering possible, and are crucial to cell phones, Wi-Fi, GPS, and so much more.

The modern interconnected economy and daily life as we know it would grind to a halt if crystal oscillators were not abundant, well designed, and reasonably affordable. But what determines oscillator pricing?

If you're looking for an oven controlled crystal oscillator (OCXO), my guess is you're interested in the best possible quartz crystal oscillator for your application. Who wouldn't be? 

The oven controlled crystal oscillator (OCXO) is near the top of the food chain when it comes to quartz-based frequency control devices, superseded only by the mighty double oven crystal oscillator (DOCXO).

In this blog, we'll review the basics of how an OCXO works, the terms you need to know, how to determine the turning point, and the differences between AT and SC crystal cuts. 

While GPS technology plays an important role in modern navigation, it's not perfect. Although GPS might perform well enough consumer usage, signal jamming or other disruptions present serious threats to military operations. 

Enter assured positioning, navigation, and timing (A-PNT), new technology that enhances traditional GPS timing. Assured PNT uses additional sources to augment GPS and prevent vulnerabilities. Its goal is to ensure that accurate positioning, navigation, and timing (PNT) is always available.

In this blog, we'll review GPS, its flaws, and other PNT systems (like the GNSS) and give you an overview of how assured PNT technology uses other systems to improve effectiveness. 

Inside every quartz oscillator is something called a crystal blank. The crystal blank is the resonating element of the oscillator that, when subjected to a voltage potential, will begin to vibrate and oscillate at its fundamental frequency.

The way the crystal blank is manufactured can have a significant impact on the oscillator's performance. In this blog, we'll be discussing how the orientation of the quartz when the crystal blank is cut can affect how your oscillator performs.

Why is it important to choose the right crystal oscillator output signal?

The output signal types of crystal oscillators can provide different benefits and drawbacks depending on what you're trying to accomplish with your product. With that said, it's important to understand signal types to avoid as much attenuating and distorting of your clock signal as possible. You'll also want to be sure you're receiving more benefits than drawbacks from the signal to meet your specific design needs.

In a perfect world, a crystal oscillator would generate a signal that remains steady, consistent, and clear with no deviations, for as long as that signal needs to be transmitted. 

But in the real world, no crystal oscillator produces a 100% perfect signal. Even if the signal is very strong and clear, there will still be tiny, random fluctuations in its waveform. This phenomenon can be represented visually in the frequency domain as sidebands on either side of the carrier. These unwanted fluctuations are referred to as phase noise.

In the blog, we'll explain why you need to measure phase noise, what the methods are for measuring it, and 

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.