A Primer on RF Filters for Software-defined Radio
An RF filter is a hardware device that is used to limit signals in certain frequency bands while allowing signals of interest at other frequencies to pass through. Filters are …
Software-defined Radios and Bias Tees
We wrote about Bias Tees and their applications within the context of Software-defined Radios in a previous post. The primary use of a bias tee in SDR is to enable …
How Not to Break your Software-defined Radio (SDR) Hardware – Part 2
In Part 1 of this article, we covered RF-related precautions on the transmit and receive sections of a Software-defined Radio. In this article we will cover other precautions including Mechanical …
How Not to Break your Software-defined Radio (SDR) Hardware – Part 1
Software-defined radio (SDR) can be easily damaged if proper care is not taken during use. In part one of this article series, let’s take a look at the most important …
What is a Bias Tee?
Updated January 2021 A bias tee or Bias-T is one of the most useful Software-defined Radio (SDR) accessories you have likely never heard of. Low Noise Amplifiers are used to …
What is Software-defined Radio used for?
Software-defined Radio technologies have become increasingly accessible these days with low-cost devices ranging in price between $20 and $300 and offering varying levels of performance. Here is a list describing …
Should I place a Low Noise Amplifier Before or After a Filter?
Most Software-defined Radios operate over a large frequency range. The RTL-SDR for instance can operate from 500 kHz to 1.7 GHz while the HackRF can operate from 1 MHz to …
An Introduction to Low Noise Amplifier Specifications
A Low Noise Amplifier (LNA) is an electronic device that amplifies weak signals at its input without adding significant noise to the output signal. Such amplifiers are typically used in …
FM Notch Filters – why you need one with most SDRs
FM radio was invented in 1933 and is one of the most popular broadcast technologies out there. FM broadcast signals in most places in the world occupy the frequency range …
How does Software-defined Radio (SDR) work?
Updated January 2021 Most of us are familiar with communication devices such as AM/FM radios, Smart phones and Two-way radios. The radios within these devices are comprised of hardware in …