Understanding dB, aka go easy on your HF amplifier!
I was listening to a couple of guys on the 20m band today and they were discussing amplifiers… “Yeah, this amplifier will do 1500W. The last one I had would only do 1000W so...
I was listening to a couple of guys on the 20m band today and they were discussing amplifiers… “Yeah, this amplifier will do 1500W. The last one I had would only do 1000W so...
Overview A tuning pulser is a device which generates a series of short-duty cycle tone bursts which are applied to the audio input of a transmitter. Instead of tuning up a tube linear amplifier...
You can not make a very good antenna using insulators like PVC tubing, drinking straws, or nylon rope. I think we can all agree on that. Why? Materials like plastic are electrical insulators, and...
In this article, I’m going to cover Noise Figure, Noise Factor, Noise Power, Receiver Bandwidth, and how they can affect overall radio receiver performance. Contrary to popular belief, these metrics have nothing to do...
I usually have a respectable HF noise floor at home, for which I count myself lucky in today’s sea of cheaply made switching power supplies. However, we were expecting some severe winter weather a...
While this post is written with the UR6QW processor in mind, it contains information which is widely applicable. There is some concern about connecting dynamic microphones to devices which commonly use electret condenser microphones....
The RF world is full of esoteric terminology, and not least of these is characteristic impedance, or Z0. Most coaxial cables have a characteristic impedance of 50 or 75 ohms. If you want to...
Introduction QUCS, or Quite Universal Circuit Simulator, is a freeware utility that allows you to draw circuit schematics, and perform AC & DC simulation, noise simulation (for S-parameters, and AC simulations), S-parameter simulation, and...
Antenna tuners seem to be some of the most misunderstood devices in all of amateur radio. In this article, I’ll try to explain what is happening when you use an antenna tuner. I’ll try...
Amateur radio transceivers demand power supplies which have a large current capacity. The average 100 watt radio transceiver requires over 20 Amps when in transmit mode. Overview A linear power supply uses a large...