valve design

A 6m portable 4 element quad - This antenna is based on a design for a portable 2 element 6m Quad by VE7CA, which is featured in the 19th Edition of the ARRL Antenna Handbook

A 16 Turn S-Band Helix - This design represents the smallest practical antenna for Oscar-13 mode-S. Perfect beacon reception at all times is possible, and acceptable SSB even at 43,000 km range.

Design your Own Super J Pole - a Javascript for calculating the lengths of tubing to be used for the construction of a Super J-Pole.

N4EKV.COM - Antenna Tuners - Homebrew balanced-L antenna tuner. Covers 160-10m. Designed specifically for balanced feedlines.

PAC-12 Vertical portable antenna - Build the PAC-12 Antenna a multi-band portable vertical designed by KA5DVS, here’s an award-winning, easy-to-homebrew, multi-band portable vertical antenna designed by long-time antenna aficionado James Bennett, KA5DVS. He’s documented the design and construction plans for a portable antenna

Helical Antenna for 2.4 GHz and 802.11b - The following page details construction of a Helical antenna based on the superb design by Jason Hecker.

How to build a tin can waveguide antenna  ^pop - Looking for an inexpensive way to increase the range of your wireless network? A tin can waveguide antenna, or Cantenna, may be just the ticket. This design can be built for under $5 U.S. and reuses a food, juice, or other tin can.

Pringles Yagi Antenna - Design and build a Pringles Yagi antenna for 2.4Ghz.

Planet Ham - Planet Ham is a website designed to aggregate blogs produced by Amateur Radio enthusiasts. The aim is to provide a central directory of Amateur Radio blogs so that interested browsers can visit subscribers sites and read about the various aspects of the hobby in detail

The KO6YD Screwdriver Antenna Memory - The Screwdriver Antenna Memory (SAM) product is designed to enhance the mobile antenna commonly called the "Screw Driver". It replaces your current control unit and provides an automated memory feature that eliminates the visual coil tuning method commonly used.

MicroSignals - MicroSignals produces a line of RF and IF signal processing components that offer high performance at an exceptional value. To achieve this MicroSignals began with an engineering team that possessed an excellent background in RF Transformer and Balun design.

Sunstone Circuits Priority listing - Sunstone Circuits is your easiest source for quoting and ordering printed circuit boards online. We are three respected brands in one: PCBexpress quickturn boards, PCBpro.com full-featured and design-checked boards, and PCB123 design software.

Peter W. Dahl Co. - Custom transformers by Mr. Dahl has been designing specialty transformers and reactors for over 35 years, and has been a licensed Ham radio operator, K0BIT, since 1955.

Starline Electronics - Full-size Professional Circumaural (closed type) Stereo Headphone Monitor designed for studio use, swl and amateur radio.

Rotating Tower Systems - Using our components you can build a rotating tower with greater capability than 3-4 static towers. A rotating tower allows common rotation of HF stacked arrays, VHF and UHF arrays, and antennas mounted at optimum heights. Component design also allows tower shunt loading and end support for wire antennas

Q15X25 - Q15X25 is a packet modem with a KISS/AX.25 interface designed for HF transmission of AX.25 packets and TCP/IP using Automatic Repeat reQuest (ARQ) and forward error correction (FEC).

JT65 - JT65 is a digital protocol intended for Amateur Radio communication with extremely weak signals. It was designed to optimize Earth-Moon-Earth (EME) contacts on the VHF bands, and conforms efficiently to the established standards and procedures for such QSOs.

Xtal Set Society, Inc - The society publishes several books about crystal radio. Sell crystal set projects, tips for crystal radio design, ham radio kits, radio parts and common radio electronic components

Qsl factory - qsl cards - Qsl card printer and designer offering truly original styles of quality single and double sided color qsl cards, both ready-made and custom.

RadioLabs - Radio, Wireless and Beyond - Specialize in engineering, design and repair of all rf equipment. Dealer for two way radios, scanners, shortwave radios, wi-fi antennas, wifi amplifiers. Based in Fortuna, California.

MrHamRadio.com - Custom Printed T-Shirts - Custom Design T-Shirt with No Minimum order (you can buy just 1) and NO Setup Fee. Will transfer your Favorite Images from JPEG's and E-mail attachments and from photo prints to Custom T-shirts with unbelievable Crispiness and Clarity of true Color Reproduction. Our image transfer paper is 11.5" x 8" heavy duty industrial grade.

Duncan's Amp Pages - This is an internet resource for those interested in guitar amplifiers, vacuum tubes, and design tools such as SPICE modelling.

Delabs technologies Product Design and Engineering - Around 200 electronic circuits in pdf format or images, There are also over 1000 links to useful electronics, freeware, open source websites. There are some 100 useful documents, software and pcbs too. Mainly industrial electronics, instrumentation. Covers Various aspects of electronics and basics of circuit design.

Grounding and RFI - Described system was designed to provide a high level of lightning protection - there are three levels of defense to guard against let-through. It isn't perfect, but does, however, follow good guidelines and shows measured improvements in RFI reduction.

Prototype SWR meter for 2.45Ghz - Testing antenna's is a lot easier if you have a good swr meter this is a prototype of a design by g7eyt.