Introduction In a recent post I was considering a hypothetical 2m amateur radio repeater and studying its VHF coverage with a Yagi antenna (Ref.1). In the process I read an article describing the difference in results of using the Longley-Rice & ITWOM propagation models (Ref2). The researchers used the Radio Mobile program developed by Roger… Continue reading VHF Marine Propagation with Radio Mobile
Category: Telecommunications
Telecommunications: Propagation, HF, VHF, UHF, uWave
VHF/UHF Whip Antenna Testing with NanoVNA
Introduction The NanoVNA is a very compact and useful instrument that can be used to test a variety of antennas (Ref.1/8). So far I have tested most of my antennas with the exception of a few whip antennas that are used with the RTL-SDR. In this post I am testing a compact VHF (136-174MHz)/UHF(400-470MHz) antenna.… Continue reading VHF/UHF Whip Antenna Testing with NanoVNA
RTL-SDR V5 on GNU Radio
Introduction Recently I received a lot of questions about the RTL-SDR V5 and how to get it working on GNU Radio so I decided to get one and try it out. These are my results. If you are using the RTL-SDR for the first time, you have to install the Windows driver (Ref.1). HF Reception… Continue reading RTL-SDR V5 on GNU Radio
Splat! – Antenna Patterns
Introduction Splat! (Ref.1) is a very versatile propagation prediction program that I discussed in several previous posts. In my first post, I looked at installation on Windows and Linux, how to obtain the digital elevation data files, create .qth & .lrp files, and run a simple point to point analysis (Ref.2). In the second and… Continue reading Splat! – Antenna Patterns
RTL-SDR for VHF Air_AM/VHF Marine_FM Weather & Cyber Security
Introduction The RTL-SDR can conveniently be used to check both VHF Air & VHF Marine weather. Figure 1 shows the receive schematic. Recently a significant cyber security outage affected millions of Windows computers all around the world. I offer two simple solutions that can be easily applied before more outages happen. Receive Block Diagram Figure… Continue reading RTL-SDR for VHF Air_AM/VHF Marine_FM Weather & Cyber Security