W3FF Portable Dipolepop
- This is the antenna w3ff designed for his walking portable station. It is a dipole constructed out of the plastic plumbing pipe CPVC. There are telescoping whips at the ends of each side of the dipole, and these whips are adjusted to bring the antenna into resonance on each of five HF Bands 10, 12, 15, 17, and 20 Meters
- Whenever you choose a coax feedline, the frequency of operation is a very important consideration. Over the operating bandwidth of the coax the VSWR is low, typically 1.2:1 or better. Insertion loss is also an important parameter. It is usually specified in dB/foot and is a linear relationship.
SWR: Maximum allowable VSWR
- VSWR (voltage-standing-wave-ratio) represents the degree with which an antenna is "matched" to the system impedance. Most modern antennas do not require any tuning for optimum performance. VSWR is one of the easiest parameters to measure and VSWR meters are becoming very popular antenna installation tools
- BesserNet Reflectometer is a fun SWR calculator and simulator Java applet
Yagi Element Mounting Considerations
- One of the most important considerations when designing and building a Yagi antenna is the method used to attach the elements to a boom. This is true because the boom influences the electrical length of the elements. In this article JH Reisert explain with drawings techniques on mounting yagi antenna elements to a boom
A $20 HF mobile antenna
- A few hours of fun with PVC and wire and
you’ve got yourself a respectable road radiator. The antenna consists of little more than some PVC pipe topped by a RadioShack replacement whip antenna and a couple of coils made from a small roll of #14 house wire.
Antenna Selection Made Easy
- This page will help you answer important questions about antenna selection before you talk to a supplier. After reading this paper, you should be able to better determine the most important parameters you need to know for your antenna selection criteria.
Antenna Polarization notes
- Antenna polarization is a very important consideration when choosing and installing an antenna. Most communications systems use either vertical, horizontal or circular polarization. Knowing the difference between polarizations and how to maximize their benefit is very important to the antenna user.
- An antenna study guide by NZART, cover basic topics like dipoles, wave lenght calculation, baluns, beams, dummy loads, and measurements.
Automatic Identification Systems (AIS)
- Automatic identification systems (AISs) are designed to be capable of providing information about the ship to other ships and to coastal authorities automatically.
Amateur Radio RF Safety Calculator
- University of Texas Amateur Radio Club RF-Calculator. This is a main beam power density estimation program intended for use as part of a routine evaluation of RF safety compliance with FCC regulations
RF Coaxial Connectors
- RF coax(ial) connectors are a vital link in the radio spectrum. Coax connectors are often used to interface two units such as the antenna to a transmission line, a receiver or a transmitter. The proper choice of a coax connector will facilitate this interface.