This video briefly explains how to influence a crystal oscillator’s frequency by introducing reactive elements such as trim capacitors and inductors:
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Search Results for: crystal oscillator
Overtone Crystal Oscillator
Crystals with higher frequencies than about 30 MHz are almost exclusively overtone crystals. Such a crystal is intended to be used on an odd multiple of it’s fundamental frequency. Unfortunately, the crystal doesn’t want to resonate on it’s overtone frequency voluntarily, the oscillator circuit needs to force the correct overtone. For a little 2m band […]
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Simple oscillator as crystal tester
For homebrew crystal filters such as Cohn-Type or Ladder-Type filters it is often necessary to select crystals within 10 – 50 Hz of the target frequency. To make the selection process a little bit more pleasant, I designed this little test circuit. It is basically just a very simple oscillator utilizing a hand full of […]
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Crystal controlled listening device
There are tons of circuits for listening devices available on the internet. For the most part, they all have in common that they are virtually useless. This article shows how to build a reliable, small and inexpensive listening device using a PLL clock multiplier and a standard crystal. Most audio listening devices, also called spy […]
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Low Noise Oscillator Design
The overall performance of any RF circuit in regards of it’s phase noise and spectral purity depends significantly on the frequency generating circuitry, commonly an oscillator. Low noise oscillators with high spectral purity are neither witchcraft nor black magic. Many people think the design of oscillators is black magic as such circuits usually either work […]
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ICS501 / ICS501 VHF Experiments
The ICS501 / ICS511 from Renesas are easy to use, fully integrated clock multipliers for output frequencies up to 200 MHz. What makes them particuarly interesting is the integrated crystal oscillator circuit and ability to produce some fractional multiples, such as 6.25 or 2.5. So let’s find out if they’re interesting for the hobbyist who […]
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Look Inside: Teledyne LeCroy HDO4024
True beauty lies within, or so they say. For an exclusive look under the hood, I decided to break the warranty seal on my Teledyne LeCroy HDO4024. It took me a while to debate with myself whether or not I should void the warranty on this scope. Curiosity won and I couldn’t resist, I just […]
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Review: Abracon ABFT Frequency Translators
In March, 2012, Abracon announced the production of ultra-low jitter, VCXO based frequency translators / jitter attenuators. This is supposed to resolve some problems that accompany classic PLL-based designs at an affordable price. Now, the ABFT frequency translators / jitter attenuators are available on the market and it’s time to have a closer look. The […]
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ICS501 – Integrated PLL Clock Multiplier
Before clock multiplier circuits existed, they had to be implemented with discrete parts. This took up quite a bit time in design and prototyping. Luckily the days are over and we can use integrated clock multipliers such as the LOCO™ PLL clock multiplier ICS501. I stumbled across a box of ICS501 PLL clock multipliers from […]
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C-Band DRO LNB Teardown
A low-noise block downconverter (LNB) is a key element in a satellite receiver system and is responsible for converting the relatively high frequency of the received signal into the more convenient L-Band. But how do they work and what do they look like on the inside? Let’s have a look! From a theoretical standpoint, a […]
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