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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Electronics
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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Demystifying RF Circuit Design – The art of Voodoo
Mike from Mikeselectricstuff did a very neat teardown of an Anritsu spectrum analyzer. However, he did call RF circuit design Voodoo and implied it’s some sort of black art. But is it really? Let’s have a look. If you watched the video of Mike [1] from Mikeselectricstuff tearing down an Anritsu spectrum analyzer, you might […]
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Switched Capacitor (SC) comb filter
Switched-capacitor filters are great alternatives to standard LC filters. Their frequency response can easily be controlled solely by an external clock signal. In this short article we will have a closer look at an extremely narrow switched-capacitor comb filter. For a homebrew EAS (Emergency Alert System) decoder I needed a very selective band pass filter […]
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Review: Abracon ABPSM-ULN-A – Precision Power Supply Module
When bench testing noise sensitive circuits, one needs an ultra clean power source. Low noise lab power supplies are usually bulky and expensive. Abracon challenges both the bulkiness and the expensiveness with their new low noise pocket sized ABPSM-ULN-A ultra low noise power supply module. With the ABPSM-ULN-A, Abracon intends to set a new standard […]
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Review: Freescale FRDM-KL25Z development platform for Kinetis L-Series MCUs
Freescale’s new low-cost development platform FRDM-KL25Z featuring Freescale Semiconductor’s ARM® Cortex™-M0+ processor-based high performance, low-power Kinetis L series 32-bit MCUs has launched last Tuesday. Let’s check it out. The FRDM-KL25Z “Freedom” development platform is an extremely inexpensive development board with a Kinetis KL2 Family 32-bit ARM®CortexTM-M0+ MCU [1]. The Kinetis L-Series MCUs promise true 32-bit […]
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Review: Abracon Sync’n Go – Portable Precision Frequency Reference
Most professional devices which require high accuracy and precision have an input for some sort of external frequency reference. The frequency 10 MHz is an industry standard particularly for test equipment. Most reference generators are designed for lab use and therefore are bulky and unsuitable for portable use. Abracon now offers a pocket-sized portable solution. […]
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Why you should use high quality soldering tips
That a chain is only as strong as the weakest link should be common sense. Yet I see many people investing into extremely cheap soldering irons and then being surprised about their weak performance. Let’s compare tips of a budget soldering iron and a professional brand soldering iron. A while back I read an article […]
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Modifying a 240V / 50 Hz switch mode power supply for 120 V / 60 Hz
Most switch mode power supplies can handle both 120 or 240 Volts just fine. They usually either have a switch to select the input voltage or are simply designed to cover the whole range to begin with. But what if one needs to operate a switch mode power supply, that is exclusively designed for 240 […]
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Freescale’s Kinetis L-Series ARM® Cortex™-M0+ based MCUs
Freescale announced a new line of ARM® Cortex™-M0+ based microcontrollers, the Kinetis L Series. The MCUs are supposed to offer the performance of a real 32-bit MCU at the price and energy rating of an 8-bit microcontroller. A tight budget and low power requirements used to limit design engineers to 8-bit and 16-bit MCUs. Freescale’s […]
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