VHF LDMOS Power Amplifier Experiments

The NXP MRF101 series high ruggedness N-channel Enhancement-mode lateral MOSFETs promise over 100 Watt CW output power and slightly over 20 dB gain from 1.8 MHz all the way up to 250 MHz. Their mismatch insensitivity for a VSWR of greater than 65:1 without significant device degradation makes these devices extremely interesting for amateur radio […]
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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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Diplexer with integrated Bias-T (Triplexer) for QO-100 and X-band microwave reception using LNBs

This article shows how to build a simple Triplexer (Diplexer plus integrated DC Bias-T) for use with commercial TV LNBs for QO-100 or X-band microwave experiments. Introduction When using modified, commercial LNBs for reception of the QO-100 amateur radio satellite or X-band microwave experiments, it is necessary to pass a clock-reference signal, a DC supply […]
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Tremolo DSP Effect for Arduino

This article continues my newly acquired interest in implementing digital signal processing algorithms on the Arduino GIGA R1 by showing how to implement a tremolo effect algorithm in software. After showing how to implement an Audio Loopback Device and a DSP Diode Clipping Algorithm for Overdrive and Distortion Effects on the Arduino GIGA R1 WiFi, […]
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DSP Diode Clipping Algorithm for Overdrive and Distortion Effects

This article shows how to approximate the behaviour of a regular diode in a mathematical equation and how to subsequently implement the behaviour in software. The DSP algorithm can be modified to implement different topologies, such as single diode clipping, dual diode symmetrical soft clipping or asymmetrical clipping. The easiest way to implement distortion through […]
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Program uBlox GPS-module timepulse frequency (dynamically) with an Arduino

The uBlox GPS-modules are capable of providing various reference clock signals through the TIMEPULSE pin. By default, this pin outputs a 1 pulse-per-second (PPS) signal. For an upcoming project, a GPS disciplined oscillator (GPSDO), this output had to be adjusted to 100 kHz. Instead of using the manufactuer’s software, u-center, this task is supposed to […]
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