The signal generator is an essential tool in any electronics lab. They allow you to characterize filters, perform receiver tests, and more. Unfortunately, signal generators capable of operating in the GHz range are quite expense. Here I will demonstrate how to construct one with an affordable SDR platform: the HackRF. Using the GNU Radio DSP framework and an SDR transceiver allows us to build a high frequency signal generators at a very affordable cost.

In this article, I will cover the design of a device capable of automatically determining the origin of an RF signal using RF opaque material and other very affordable hardware. Unlike using a Yagi-Uda antenna, which has very narrow bandwidth, this design permits operation on a massive frequency range. This makes it suitable for also detecting bugs and other nefarious RF devices. Additionally, since it was designed for tracking drones, it is well suited to identifying the location of moving objects.

Here I will introduce a cost-effective design for an active electronically scanned array phased antenna system (the type used in modern fighter jets). A typical AESA has an RF transceiver at every element in the phased array (which number thousands). My design provides all the same benefits as an AESA, while utilizing just a single transceiver. This reduces the overall cost of the system and allows for specialized enhancement of the RF front end, which is not possible with a traditional AESA system.

Do you have trouble finding 18650 cells for battery build projects? So did I, until I found modem battery packs. Many modems integrate a small uninterruptible power supply to preserve operation in the event of a power outage. These packs contain 18650 cells and can be obtained cheaply and with very little wear on them.

This article will cover a method of generating an arbitrary RF time delay using a demultiplexer and microstrip lines. This is intended to be used in potential phased antenna array designs.

This article will show you how to use the HamDB API in Python to access amateur radio callsign data. This data can then be used for a plethora of projects such as automated loggers and dynamic QSL card generation.

If you use a Yaesu FT-70, the ability to charge it via USB is very convenient. This article will demonstrate how to build such a cable for just a few dollars, allowing you to charge your radio anywhere you go.