Understanding Standing Wave Ratios SWR
- We worry a lot about Standing Wave Ratio (SWR) in amateur radio since SWR is one indication of how well our antenna system is working. Most HF transceivers and antenna tuners have built in SWR meters. SWR is a measure of a transceiverís output power verses the portion of that power reflected by the antenna system By Ken Larson KJ6RZ
- 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
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
Copper J-Pole Antennas
- Conejo Valley Amateur Radio Club, article edited by Rory Eikland, KG6HCU and Ken Larson, KJ6RZ, they have had excellent experience building and using J-Pole antennas, and share their experience on planning VHF and UHF Jpole antennas.
The 5 Bands Wire-Beam
- This wire-beam has one radiator-element, feeded with 450-Ohm-Wireman-twinlead and needs an antenna-tuner. For the bands 6m, 10m, 12m, 15m, 17m and 20m bended reflector-elements are used.
The support is a cross of 4 fibreglass-fishing-rods
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.
Maximum Usable Angle
- We are all familiar with Maximum usable frequency. Maximum usable angle is the other half of the maximum usable frequency equation.
Zanesville Amateur Radio ClubPriority listing
- The Zanesville Amateur Radio Club (ZARC) is an association for the purpose of providing amateur radio communications in times of emergency: installing, maintaining, and operating a 2-meter repeater and club radio shack, and promoting amateur radio in general.
About digital modes
- The digital modes provide a wonderful opportunity for those of us who would like to work on the HF bands but find CW too difficult and SSB phone prohibitive because of interference problems. The digital modes are easy to set up and get operating, require low power and a narrow band.
- CB Radios, Scanners, Radar Detectors, Two Way Radios/GPS store. Products you can trust Cobra, Uniden, Garmin, Rocky Mountain, Whistler and more. We are your specialty store for your mobile communication needs. Based in Tampa Florida.
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.
Programming VHF/UHF Radios
- Programming a new VHF/UHF radio usually proves to be a frustrating experience for most new amateur radio operators. A new radio must first be programmed for simplex and repeater operation before it can be used to communicate with local hams.
Safety: RF awarness guidelines
- Although Amateur Radio is basically a safe activity, in recent years there has been considerable discussion and concern about
the possible hazards of electromagnetic radiation (EMR), including both RF energy and power frequency (50-60 Hz) electromagnetic fields. This section summarizes what is now known and offers safety precautions based on the research to date.