- 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
- The construction of light weight structures that support wire antennas requires some definite insight into the behavior of the materials
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 Magnetic Loop antenna for 7-21 mhz
- If you find external wire antennas obtrusive for amateur radio or short wave listening, then this is the antenna for you, is just 1 meter diameter
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.
RACOM - Radio modems
- RACOM is a Czech company specialized in design and production of radio modems and other devices for wireless data networks for radio channels from 140 to 900 MHz. RACOM radio data networks are suitable for data transfer in telemetry & SCADA applications, transaction networks, security systems, IP networks and firts of all mobile tracking and fleet management.
Telecom Product Profiles
- Telecom Product Profiles is a manufacturers' rep firm specializing in factory direct Nello Towers, monopoles, antenna mounts, shelters, and more. Factory direct Cellular, PCS, and Wireless Broadband equipment such as antennas, radios, and more. Installation, financing, and leasing options available.
Smith Chart Software
- SimSmith is a highly interactive, real time Smith chart graphing program. Circuits are constructed using drag-n-drop. Load files can be imported from the EZNEC and CocoaNEC antenna simulation software and from the AIM4170 and miniVNApro antenna analyzers. Circuits and load files can be of any size.
Key Features: SimSmith is one of the few Smith chart packages which models transmission line losses. SimSmith also allows the description of circuit elements using algebraic equations. SimSmith has only one screen and allows the screen to be resized to increase workspace or readability.
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.