Antenna Materials & Efficiency
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...
Category: Antennas
Antenna Tuners, Impedance Matching, and SWR
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...
PL-259 Soldering
Do you solder the coaxial shield to the connector body when installing a PL-259 plug? What are those holes really for? I’ve been installing PL-259 plugs onto coaxial cable since I was about 16,...
Alpha Delta Switch Arc-Plugs
I recently bought a couple of Alpha Delta coaxial switches, and noticed they come with a built-in surge arrester which can be replaced after a surge. They call them “Arc-Plugs”. These are on sale...
WSPR Antenna Comparison
Having recently raised a Off-Center Fed Dipole, and figured out how to use WSPR with my FT-991, I thought it would be interesting to compare the OCFD with my 35′ End Fed Wire. Getting...
Coaxial Cable Length Does Not Change Antenna SWR
I’ve heard this for decades, and I first heard it when I got into CB radio when I was a kid. You’ve gotta to cut your coax to the right length if you want...
Why 50 ohms?
Coaxial cables, antennas, amplifier inputs and outputs, typically have either a 50 ohm or 75 ohm characteristic impedance. Why? It all comes down to the characteristic impedance value for maximum power transfer being 30...
Antenna Field Regions
Antenna radiation is made up of several different regions. The transitions between these regions are not distinct and changes between them are gradual. The reactive near-field region is the region close to the antenna....