Categories
Navigation Telecommunications

OpenPlotter – GRIB Files

Introduction OpenPlotter has many excellent features that we explored in previous posts (Ref.3-Ref.9). Weather information is critical for sailors and OpenPlotter features a GRIB file viewer as well as the ability to overlay this information on OpenCPN. The weather information is contained in GRIB files that can be downloaded over an internet connection either from […]

Categories
Navigation Telecommunications

RTL-SDR for AIS Shortcut

Introduction AIS Automatic Identification System for Ships is a traffic system that uses VHF transponders on vessels to periodically send out location information. It was developed by Swedish inventor Hakan Lans and is similar in concept to the ADS-B transponder system used on aircraft for position reporting. AIS uses two VHF marine channels 87B (161.975 MHz) […]

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Telecommunications

RTL-SDR for Shortwave Radiogram

Introduction Recently I read several posts on various amateur radio forums regarding the reception of Shortwave Radiogram broadcasts. VOA Radiogram was a Voice of America program that experimented with various digital transmission modes, starting in March 2013. It was superseded by Shortwave Radiogram (Ref.1). I decided I would try reception using the very popular RTL-SDR […]

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Electronics Navigation Telecommunications

I2C Programming & Scope Detection

Introduction Recently I have been working with various sensors such as a magnetometer, gyroscope and accelerometer for use in navigational systems (Ref.1). All these sensors are accessed using the I2C protocol. Over the past several years I have worked with various HF synthesizers that were also programmed via I2C. I used a Tektronix TDS210 digital […]

Categories
Navigation Telecommunications

OpenPlotter – RTL-SDR for VHF/AIS

Introduction OpenPlotter (Ref.1) is a Linux based Operating System that runs on the Raspberry Pi computer. The Raspberry Pi is extremely popular in the education field. It is well documented, compact and requires very little power. This makes it ideal to form the basis of an electronics navigation system for a small craft. In the […]