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This article is about a home made project of a whip antenna for 2 meters band. Includes lenght of whip for all frequencies from 140 MHz to 151 MHz both in mm and inches

Operating Morse code (CW) relies on a diverse array of **telegraph keys**, each with unique characteristics and historical significance. This resource presents a personal collection of such keys, offering visual documentation and details on various models. It features early Marconi keys from the 1900s, including specific models like the Marconi Air Ministry Key and Marconi Coastal Station Keys, alongside **Vibroplex** bugs and JRC keys. The collection also highlights rare items such as the Brown Brothers Magnetic Twin Paddle Key, the Eddystone Bug Key, and Swedish SRA Ericsson Keys. Enthusiasts can view examples of GPO Double Current & Single Current Keys, Navy NATO Keys, and specialized aircraft and maritime keys. The site includes information on historical training devices like the OMNIGRAPH and a Morse Inker from 1900, providing context for the evolution of telegraphy equipment. Additionally, the resource showcases unique items like the B2 Spy Set SOE Agents Key and a WW2 Junker U-BOAT KEY, illustrating the varied applications of Morse keys throughout history. The author, G0RDO, also shares details on a home-made paddle key and invites inquiries for acquiring interesting Morse keys.

Home made LF converter, listen to signals below 300 KHz

Full article on how to build a home-made wire dipole antenna for 40 and 80 meters band. Article is fully in italian, as it was published on ARI RadioRivista, but is plenty of self explaining pictures that will guide you on homebrewing this trapped dipole antenna for the lower amateur radio bands.

An interesting rf coaxial switch project capable of handling 800-1500 W. This is a cheap home made RF coaxial switch in use by PA0FRI

This antenna is designed for stations having a difficult time putting a decent signal on 160M from small or CC&R d lots. It is a 24.5 ft. vertical antenna, made from three 10 ft. PVC sections bolted together, and half wavelength of antenna wire helically wound around the PVC sections.

A schematic diagram of a homemade direct conversion receiver for 30 meters band

A collection of projects and equiment home made for 24 GHz operations

Demonstrates the construction of a high-power 6-meter (50 MHz) amplifier, specifically designed for demanding modes like EME, TEP, and multiskip Es. It details the use of a _GU-43B_ tetrode in a grounded-cathode configuration, emphasizing the need for stabilized grid voltage and input capacitance compensation. The resource provides a comprehensive schematic, power supply design, and practical considerations for component sourcing, particularly for high-voltage and high-current sections. The builder achieved an output power of **1250 watts** with an anode current of 0.65 amperes and 3200 volts anode voltage. The article also covers the physical construction within a modified P6-31 enclosure, outlining the internal layout for RF and power supply sections, and includes photos of the completed unit. It highlights critical safety precautions for working with high voltages and reactive currents up to **20 Amperes** in the P-network.

No exotic claims are made for this antenna. Author just tried a few WSPR experiments on 40 meters and was surprised with the results. What appears below may inspire you to try something equally off-the-wall, to see what happens.

DTMF Keypad for radios without one. A project with picture and schematic diagrams to homemade a DTMF keppad

An inexpensive spectrum analyzer for the radio amateur, with a respectable performance and a quite good dynamic range. Schematic and basic information on how spectrum analyzers works.

Homemade RF limiter project, to protect the K3 receiver front-end for high radiofrequency based on the original KD9SV project.

QRSS operations on 30M with an home made dipole

An home made remote antenna tuner project that with a 6 meter random wire and two radials of about the same length, can tune from 40 to 10 meters without any issue.

A home made portable vertical antenna, that with a single 1/4 wave counterpoise wire is possible to achieve less than 1.5:1 SWR on 40, 30, and 20 meter bands. It is basically a center load, shortened ground plain vertical antenna.

A homemade interface for any android device, allow to receive and trasmitt SSTV PSK RTTY from an android tablet based on the DD7LP original project include demo of a sample DIY kit.

Crystal radio home made projects by DL2XM

A 70 MHz Transverter project with a block diagram and schematics

Homemade an external T/R switch for your vintage RTX by KB8OJH

An home made antenna switch with a Dummy Load selector. If you forget the radio is connected to the open or grounded side of the switch and you try to transmit, it is very easy to damage the finals of your transceiver.

Accurate meteorological data is crucial for optimizing antenna performance, predicting propagation, and ensuring safe tower work. This resource provides a curated inventory of weather stations, including models like the _AcuRite Atlas_ with lightning detection and the _Ambient Weather WS-2902_ WiFi Smart Weather Station, which offer real-time data on environmental factors. The product listings detail specific features such as direct-to-Wi-Fi connectivity, rainfall tracking, and temperature insights, enabling informed decision-making for various amateur radio operations. The platform categorizes products by application, featuring weather stations tailored for home and backyard use, as well as more robust systems for farm and agriculture, which can be critical for field day operations or remote station monitoring. It also highlights _Made in USA_ options, emphasizing local manufacturing and support. Beyond weather instruments, the site also presents related surveillance technology, such as the _Waggle solar CCTV camera_, designed for outdoor reliability with an IP65 weatherproof rating. This integration allows for comprehensive monitoring of remote ham radio shacks or antenna sites, combining environmental data with visual oversight.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

A fand dipole antenna home made for the 7,14,50 MHz. This article descbribes how to homebrew the antenna, hot to setup and some SWR measurements.

A home made cobweb antenna project made with easy to find parts 2-14 AWG speaker cables which are cut to 1/2 wavelength for each band and junction box with 4:1 Balun

A portable home made wire dipole antenna that works on 40 30 and 17 meters band.

An homemade 50 Ohm 140 W dummy load based on an idea and project by ON5DB Renaud.

An home made multimeter using a SparkFun multimeter kit, includes a time lapse movies of multimeter kit assembling

Homemade a custom programming cable that can works with Kenwood TM-V71A or TM-D710A

A homemade Jpole antenna for 70 cm band made with 6mm copper pipe

How to receive NOAA weather satellite with a home made QFH Antenna. This project includes some easy and efficient notch filters to suppress noise from FM frequencies

An interesting article about a homemade LiFePO4 battery pack for ham radio operations, a 10Ah LiFePO4 based on Headway 38120 Cells

A homemade delta loop antenna for six meters band in German

A home made end-fed half-wave antenna coupler with antenna lenght calculator and counterpoise calculator based on center frequency. Includes pictures and drawings along to antenna homebrewing instructions with a home made on air wound transformer

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

A homemade j-pole antenna for six meters band, designed to work on local repeaters, and working on the 52-53 MHz. Includes a list of needed materials and detailed description on assembling the copper tubes used to build this antenna.

A multimeter with standard resistance sorting function

An article about building home made Go Kits also using Tac-Comm tactical radio carriers

How to improve performance of your audio using a home made speech processor. In this article the author describes how to make your own speech processor providing a PCB foil pattern and with a 60mm x 60mm board.

Adapting a common PC earphone with microphone to connect to a transceiver via a homemade pre-amplifier, using a simple chip with aprox 10 db gain. Includes a schematic diagram

Homemade receiver for 80 meters band. The receiver works very well (in fact better than some of its successors), especially the AGC makes listening to 80m QSOs a real pleasure. Sensitivity is not cutting-edge, but on a full-size short-wave antenna it is by fare sensitive enough.

Online antenna calculator for homemade double biquad antenna for UMTS 3G 4G WiMAX WiFi frequencies. Article includes also a simple biquad antenna for 4g

Four or Five turn one meter loop antenna for 80 and 160 meter band. This home made receive only antena can be assembled in a small place.

The simple balcony vertical HF antenna made with plastic fishing pole. Just along the pole I install copper wire in 7 meter length. Then was installed ATU. It was used home brew tuner. For each band was used one counterpoise in length 0.8 x lambda/4

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

Using portable battery power is always a challange when operatin amateur radio in sota oprations. This article is about implementing lithium iron phosphate cells (LiFePO4) in ham radio portable operations.

The DIY 137 MHz WX SAT V-dipole antenna project details the construction of a specialized antenna for receiving weather satellite transmissions. It provides specific dimensions for the dipole elements, designed for optimal reception around the 137 MHz band, which is commonly used by NOAA and Meteor weather satellites. The resource outlines the materials required, such as aluminum tubing for elements and PVC for the support structure, along with the necessary coaxial cable and connectors. The article presents a clear, step-by-step assembly process, including how to form the V-shape and connect the feedline. It emphasizes practical considerations for mounting and weatherproofing the antenna for outdoor deployment. The design focuses on simplicity and effectiveness for amateur radio operators interested in satellite imagery. Key aspects include the precise angle of the V-dipole and the lengths of the radiating elements, which are critical for achieving the desired circular polarization response for satellite signals. The resource includes photographic documentation of the construction phases and the final mounted antenna.

A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.

The magnetic loop, thus named by the use of the magnetic component of the electromagnetic field, is a parallel circuit LC. In this article a sample project to home made a custom antenna. The circular form is often met on the commercial models but this antenna can be hexagonal, octagonal or square.

A home made RDF 3 elements Yagi that can be used for fox hunting. The particularity of this antenna is that it can be folded, in order to save space while travelling. In Dutch.