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Use 4CX10000D / 8171, RF output power of 11 KW in key-down carrier on all bands. Power was measured with a Bird 4712 wattmeter and a 25 KW slug

Freeware windows Wave Generator use the sound card's output as sine wave output. A built in sweep algorithm is used by audio hackers to measure frequency repsonses of their amplifiers

A Linux based FFT spectrum analyzer designed for time-frequency browsing and scientific data visualization. Oscilloscope waveform, statistical histogram, accumulated spectral trace,Weak Signal reception, continuos data logging, FFT Analyzer and specialized measurement windows.

An inexpensive coax switch. shows a proven inexpensive home-made antenna selection switch. If you question the use of a cheap slide switch and SO239 coax sockets, read on. Measurements in a physics lab showed there to be practically no reflection on HF and even on 70 cm the SWR was below 1.3 : 1

SWR / Wattmeter with Arduino Uno Shield. It can measure from 2 to 200 watt and SWR for HF Ham radio.

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 transceiver' s output power verses the portion of that power reflected by the antenna system

A small and inexpensive measurement device designed to determine antenna performance across the amateur bands through use of automatically collected SWR readings

This project shows how to build a 50-ohm dummy load using non-inductive resistors, oil for heat dissipation, and a simple assembly process. It enables accurate transmitter tuning, testing, and power measurement across LF to UHF bands. The setup allows meter calibration by measuring peak voltage, applying diode drop correction, and calculating RMS voltage and power precisely. Parts are inexpensive and widely available. With proper assembly, this dummy load offers extended service life, accurate readings within 2%, and a reliable alternative to costly commercial wattmeters for amateur radio applications.

Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

Esr meter to measure the equivalent serie resistance of capacitors

Short guide to build your own groundplane antenna, includes radial measurements fro warc bands

The page provides detailed instructions on how to build a double bazooka antenna for the 40 meters band. It includes information on materials needed, measurements, and assembly steps. The antenna can be configured as an extended dipole or an inverted V, offering low noise, wide bandwidth, and a 1:1 standing wave ratio. The content also offers calculations for other bands and includes photos of the antenna fabrication process.

Design and manufacture of components, instruments and systems for RF power measurement.

Match & display imped of antennas, can graphically visualize and compare two sets of measured impedances simultaneously.

A javascipt online calculator for 2 and 3 element beam antennas. Just input frequency and will diplay element dimensions and spacing. Measurements in Feet and Meters by G4VWL

This page describes a simple way to determine the main RF characteristics of a Wifi (IEEE802.11b/g wireless LAN) antenna.

Articles and original manuscripts on RF power amplifiers

The ICOM 746-Pro has acquired a history of NEC 1678G (IC-151) MMIC and driver transistor 2SK2975 failures. The failure of IC-151 appears to be a combination of ESD damage from electrostatic charge on the antenna entering IC-151, and perhaps thermal heat.

In these slides, differences between spiderbeam antenna and hexbeam antennas are explained comparing performances and measurements.

F5DQK repairing and swr measurement tests of a Cushcraft R7 Antenna

Various publications through the years have shown how the SWR measured on a shorted (or open) feed line can be used to calculate feed line attenuation

Review by G3TXQ and comparison to its modificated versions. SWR Measurements on inverted V setup and comparison from EZNEC model and a real one.

An home made SWR meter for 2.4 GHz. A DIY SWR meter that allow precise measurements and calibration of any WiFi antenna. This is test equipment everyone who build wifi antennas should have in their shack. Article is in french and include some videos.

This document details the design and construction of a Vinecom 6N4 dual-band Yagi antenna for the 50MHz (6-meter) and 70MHz (4-meter) amateur radio bands. The antenna features 9 total elements (4 elements for 50MHz, 5 elements for 70MHz) on a 4.236-meter aluminum boom. Computer simulations using MMANA software predict 7.21 dBd gain on both bands with front-to-back ratios of 16.01dB (6m) and 15.37dB (4m). The design uses 12.7mm diameter elements mounted on a 32mm square boom, weighing 5.7kg total. Practical measurements with an MFJ-269 analyzer confirmed good SWR performance across both bands after element length adjustments.

A re-usable control & computing platform for antenna measurement, PSK31 digital modems, audio filtering, signal source & VFO, memory keyer by AMQRP

2M Yagi made from Measuing Tape by NT1K

When experimenting on an antenna it's often important to determine its feedpoint impedance at various frequencies across the operating band. It's easy enough to measure SWR, but sometimes we need to know more detail than this

This antenna analyzer measures complex impedance over the 1.6 - 33 MHz HF spectrum

The Yagi-Uda antenna, information on basic design, project and measure of Yagi-Uda antenna, include free repository/sample of beam antenna.

Italian page about a home made a 1 to 40 balun with pictures and measurements on HF bands.

A Loop Fed Array Yagi antenna for 50 MHz featuring 11 dBi gain and 23 f/b ratio. In this excellent page the author even includes a detailed drawing in DWG format, with element lenght and spacing measures, in a separa file a full list of material list needed to build this yagi antenna including source and price, the EZnec file for this antenna plan, and a lot of pictures of this LFA Yagi for 50 Mhz. A ten page PDF file containing all infos, is also available to download.

QST Magazine Product Reviews - Key Measurements Summary - HF-Transceivers or Receivers. Compares Yaesu FTDX5000, Elecraft K3, Flex 5000 and Kenwood TS-590S

Homebrew VNA capable of both transmission and reflection measurements from 0.05 to 60 MHz

This article compares two commercial vertical antennas for the 4-meter amateur radio band: the Watson WVB-70 half-wave and the Sirio CX4-71. The Watson measures 2.03m in length, costs around £40, and exhibited adequate performance but required additional waterproofing after rain affected its VSWR readings. The longer Sirio CX4-71 (3.02m) performed noticeably better, delivering signals approximately 2 S-points stronger than the Watson. The Sirio demonstrated high build quality, a stable 1.2-1.4:1 VSWR, and weather resilience, though minor VSWR fluctuations were observed during rain and frost. Both antennas are half-wave designs requiring no ground plane radials.

Measurements for building a full wave loop using wire

This video shows one way to use a scope and function generator to measure the length of a piece of coax transmission line as well as estimate its impedance

Electonic kits, for adio,hi-fi , meteo, gadjets, medical and measure.

This article contains the measurements for building a full wave loop using wire and length of 1/4 Wave Coax Matching Transformer

The 2 metre fox-or transmitter is a small low power transmitter which mounts in a small plasic pipe and runs off two AA batteries. The board measures just 12mm by 70mm.

Use this online calculator to determine the length of a quarter-wave antenna from the frequency. Both metric and English units of measurement are supported.

A simple 50 ohm dummy load to test transmitters. includes a simple RF diode detector to measure the peak voltage, and calculate the power

The electrical characteristics of an antenna that are of interest to obtain by direct measurement are the frequency at which the antenna is tuned, the gain and radiation pattern

Use this online calculator to determine the length of a dipole antenna from the frequency. Both metric and English units of measurement are supported.

Use this online calculator to determine the length of a full-wave loop antenna from the frequency. Both metric and English units of measurement are supported. Quarter-wave matching section lengths are also calculated.

A chart presenting the results of impedance measurements made on a variety of common-mode choke implementations across the frequency range 1MHz to 30MHz by G3TXQ

Millimeterwave/Microwave transmission lines and components, Cryogenic temperature application transmission cables and systems, Permittivity(Dielectric rate) and Permeabillity measurement systems, Antennas, Radar systems

Used test equipment, used electronic test equipment, refurbished test equipment and other pre-owned electronic test and measurement equipment to buy or rent.

A post about the construction and measurements of a Resonant Feedline Dipole cut for the 10M band

QST Magazine Product Reviews - Key Measurements Summary - HF-Transceivers or Receiver and Linear Amplifiers

Accurate calibration of your receiver and sound card is necessary for good results with the weak signal modes in use at LF. Modern receivers with master oscillators that are synthesized to provide all conversion frequencies greatly simplify the process. This article describes a method of making the necessary measurements and adjustments to an ICOM R75 receiver and a sound card, using the ARGO software