tube design

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

Antennas for 136kHz - A very long and exaustive documentation on building antennas for 136 khz. Includes links to antenna design software for longwave

VHF/UHF Yagi Antenna Design  ^{updated  pop} - Design your vhf yagi antenna online, a JavaScript enhanced web page that implements the design of an antenna in the VHF, UHF by K7MEM

New HF antenna HB9ABX  ^{updated  pop} - A new, revolutionary design allows the construction of small HF antennas, which provide the same efficiency as large antennas. This antenna can be built for all HF bands, from 10 to 80 m.

Tom's Antique Radio Repair - Specializing in antique, vintage and tube radio repair, all makes. Transistor radio repair- from the 50's to the present. Free estimates.

DF3CB BV QSL Management and printing - DF3CB site, contesting, and software BV is a professional freeware software for the QSL Management and Label/QSL Printing under Windows developed and distributed by Bernd Koch, DF3CB, since 1989. It is mainly designed for the contester and QSL manager with high QSL quantities but useful for all other QSL'ing purposes as well. Includes logging features

K8ZT's Ham Radio Resources - K8ZT's Extensive Ham Radio Resources about QRP, Vanity Callsigns, Software, Maps, Kent State, Shack Design, Argonaut, Sommer, Log Analysis

Star Antenna  ^updated - Communication Electronic designs, manufactures and markets antennas for fixed wireless and mobile wireless applications in a wide range of frequency bands.

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.

CAP Wireless Amplifiers - Design and manufacture application specific microwave and RF amplifiers, upconverters, downconverters and multifunction assemblies.

Space Weather Education - Special space weather course designed to teach individuals without any background how to predict space weather

SB-220 / 200 Amplifier with Solid-State Transceivers - Using Solid-State Transceivers With Older Tube Amplifiers, some Hines and Kinks on the Heath SB-220/200 that can be useful in your application

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.

N9TEW tubes - N9TEW is supplier of vacuum tubes for ham,audio & antique radio purposes.

Rebuilt Power Vacuum Tubes - ECONCO has been rebuilding vacuum tubes for more than 30 years. Our commitment to quality, and concern for the environment has won us the acclaim of clients worldwide.

Electron Tube and Vacuum tube - The Electron Tube and Vacuum Tube Specialists. Electron tubes are our only business. Large inventory of of current and obsolete electron tubes.

Electron Tubes and Vacuum Tubes for Industry - Electron tube and vacuum tube stock-list with prices 4. Audio, broadcast and industrial tubes, triodes, tetrodes, thyratrons, ignitrons, vidicons and CRT's, microwave devices, nixies and receiving types + Bird RF devices and test equipment. Quality tubes at reasonable prices with many hard to find items available

APRS-Beacon - The purpose of the APRS-Beacon is to provide simple APRS-compatible position beacons for up to three Objects. It is designed to 'stand alone' and does not monitor other traffic on the frequency. It can use a single-port TNC (in 'native' mode), a single- or dual-port TNC in Kiss mode or the AGW Packet Engine in order to transmit on up to four radio ports.(When running with AGWPE, APRS-Beacon will also work with Windows 2000)

HamCalc v1.3  ^pop - By G4VWL, HamCalc is collection of calculators for radio amateurs: Antenna ERP calculations. Attenuators. Audio Filter design.Coil Winding. Decibels. Great Circles map and calculator HF Filters HF Traps Metric conversions OP Amps QRA Locator to Latitude/Longitude (and back) Radio Horizon calculator Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations

SmartSmith - A smarter version of the Smith Chart program. It allows you to dynamically generate impedance point plots as you configure each design element of an impedance matching network. Has an extensive Help file with a Wizard that tells you what steps to take in designing a matching network for a given load impedance. Complete Windows installation kit by w9dmk

Baudline signal analyzer - 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.

Packet Terminal Interface - Simple Windows based TNC interface program Designed for ARES operation, simple operator interface to connect and perform communication functions, control operator programs screens before operations Both receive and transmit screens Simple Windows based TNC interface program Designed for ARES operation Simple operator interface to connect and perform communication functions Control operator programs screens before operations Both receive and transmit screens

Shortwave Log (SWLog) - Shortwave Log, SWLog is a comprehensive logging and radio control program. While designed for shortwave and mediumwave listening, the program is quite adept when listening to longwave, utility, or amateur radio. Support Icom Drake TenTec Yaesu JRC and lowe receivers.

QRM and noise reduction Priority listing - You will find on these pages my experiences and results on antennas and local/non-local QRM/noise reduction. Using a broadband vertical active magnetic loop and a home made / designed broadband amplifier. Two vertical magnetic Alford loops are used in an array. Analog and Digital Signal Processing and a dual phase coherent Software Defined Radio (SDR) are used. By PA0SIM

A 80/40m Direct Conversion HF Receiver with DDS VFO - Juha (OH2NLT) and Matti (OH7SV) have designed JUMA-RX1, an award winning 80/40m direct conversion HF receiver with highly accurate direct digital synthesis VFO. The receiver is very compact, because it constructed using surface mount components. No coils need to be wound to construct this receiver!