Introduction In a previous post, I discussed how to use the Friis equation to determine the free space loss and receive level between a transmitter and receiver (Ref.1). Let’s consider an example that I saw in a recent sailing forum. The discussion was around the range of a typical marine VHF transmitter using a quality… Continue reading Splat! – Marine VHF Propagation
Category: Navigation
Navigation: Celestial, Sextant, Equipment
RTL-SDR for EPIRB
Introduction EPIRB or Emergency Position Indicating Radio Beacon Station is an emergency transmitting device that blue water sailors or explorers can use in case of distress. They have proven their worth over the years and are absolutely essential for anyone wanting to wander off the grid (Ref.1). At least 2000 people have been saved every… Continue reading RTL-SDR for EPIRB
RTL-SDR for LF Beacons
Introduction In my previous post (Ref.1) I examined how the RTL-SDR with the up converter can be used to receive the LF/MF/HF bands. Low power radio navigation beacons are located in the LF band and can be received by the RTL-SDR. Figure 1 shows a table of LF radio navigation beacons located in the Toronto… Continue reading RTL-SDR for LF Beacons
RTL-SDR for HF 0-30MHz
Introduction The standard RTL-SDR receives from 25 – 1725MHz, which does not include the LF band from 30-300KHz, the MF band from 300KHz – 3MHz and the HF band from 3 – 30MHz. However with the use of an up-converter, these bands can be received (100KHz – 65MHz). Fig.1 shows the 1st version of the… Continue reading RTL-SDR for HF 0-30MHz
Celestial Navigation Basics – Aim Off
The sun is shining, it’s early morning and I’m on my deck, Colombian coffee in hand, reading a fantastic book “China Clipper: The Age of the Great Flying Boats” by Robert Gandt (Ref.1). It is the amazing story of the American airline Pan Am crossing the Pacific in 1935. In order to fly safely with… Continue reading Celestial Navigation Basics – Aim Off