When parts are being used in military or aerospace applications they need to meet special quality standards. Using off-the-shelf parts is a big no-go and should be avoided at all times. While inventorying all my electronic parts, I stumbled across a few old forgotten parts from a fairly old project which was designed according to […]
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Electronics
Microcontroller Controlled Police Strobe Light
Circuits with flashing LEDs and amazing color combinations are pretty popular. This is probably because they are not only simple but one can literally see the results instantly. Let’s have a look at a microcontroller controlled police strobe light using an ATtiny45 from Atmel. LED flashing circuits have been around for ages and probably always […]
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Resuscitate Atmel AVR from CKSEL Fuse-Bit Death
The most common way to ‘kill’ a Atmel AVR microcontroller is by programming fuse bits wrong. Sooner or later every Atmel AVR enthusiast will stumble across a fuse-bit related problem. The most common mistake, a wrong clock source selection through the CKSEL fuse-bit, can be fixed easily. The fuse-bits CKSEL0 through CKSEL3 let the microcontroller […]
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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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Atmel AVRISP mkII and BASCOM AVR
More and more computers (especially laptops) aren’t equipped with serial and / or parallel ports anymore. Therefore, more and more programming interfaces utilize USB instead. However, some people are extremely attached to their older serial / parallel programmers and often oversee how a USB based device can simplify their life a lot. Atmels’s AVRISP mkII […]
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AOCJY1 series high stability OCXOs from Abracon
An Oven Controlled Crystal Oscillator (OCXO) is used wherever one needs a highly accurate and precise frequency reference. Abracon manufactures a series of affordable off-the-shelf OCXOs, which are due to their low price and outstanding performance particularly suitable for homebrew designs. Abracon’s AOCJY1 series offers various through-hole OCXOs with several possible frequencies between 10 MHz […]
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Simple VHF tracking device
Little spy bugs and tracking devices are generally very popular circuits in the electronics community. This is probably because the user gets to feel like James Bond and other special agents for a while. Let’s have a look at a simple tracking device. Spy bugs and tracking devices are not only very popular in the […]
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How it works: Quadrature detector
Many integrated FM quadrature demodulation circuits, such as the MC3361 or MC3362, have a defined LC tank circuit that creates a specific phase shift of 90 degrees at the center frequency of the demodulator. Let’s take a closer in depth look at how they work. A quadrature demodulator for FM signals consists out of two […]
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Exclusive OR (XOR) gate based phase detector
A phase detector generates a voltage proportional to the difference in phase between two signals. They are used in Phase-Locked-Loop (PLL) designs and PM / FM demodulator circuits. But how do they work? I promised in a previous blog article titled ‘No Tune NE602 / NE612 FM Demodulator’ that I would explain how a quadrature […]
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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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