Search results

A dual driven antenna for the 6 meters band.

Demonstrates the construction of two distinct wideband RF preamplifiers, detailing their component requirements and performance characteristics. The first design leverages monolithic microwave integrated circuits (MMICs) such as the MAR-6, MAR-8, or PGA103, offering a broad frequency response from DC to 2 GHz with a gain of 22.5 dB at 100 MHz and a noise figure typically below 3 dB. This MMIC-based amplifier incorporates protection against power supply transients and features a 50 Ohm input/output impedance, operating from an 8-20 volt supply with low current drain. The second preamplifier design utilizes a BSX-20 transistor, providing amplification across the 14 MHz to 550 MHz range. This simpler, more economical build achieves an average gain of 12 dB at 145 MHz and a noise figure of approximately 1.1 dB. It operates from a 7-15 volt battery supply with a current draw of 6 mA. Both projects emphasize critical construction techniques, such as maintaining short RF connections, ensuring 50 Ohm impedance paths, and mounting the circuit within a shielded enclosure to optimize performance and minimize noise. The resource also discusses phantom power options for antenna-mounted preamplifiers and precautions for use with transceivers, including output protection diodes and static bleeders.

An interesting and very detailed report analysis of three populare HF+6m transceivers. Yaesu FT-950, ICOM IC-7410 and the Kenwood TS-590S by AB4OJ

A six meter Moxon rectangle antenna. Includes high definition pictures and a detailed drawing by KG4JJH

RF power meter, dummy load, project

706 MKIIG picture and specifications by rigpix db

VA3EXT 5 element beam antenna for 6 meters band

easily design your cable, pick connectors and cable, print drawing, get immediate quote and place order, all online.

This is a compact three transistor regenerative general coverage receiver with fixed feedback

A complete review of Icom IC-706 review published in 1999 by QST

Wire beam antenna for the bands 6m, 10m, 12m, 15m, 17m and 20m

A five element quad antenna for 144 MHz DIY Project. This 2 Meter 5 Element Quad antenna was modeled using EZNEC, with a boom from a UHF TV antenna and CPVC pipe for spreaders. Constructed for 146MHz, it exhibits a gain of 10.7dB and an impedance of 75 ohms. Real-world results surpass the HT antenna, reaching over 20 repeaters up to 75 miles away. The design, costing around $10, employs simple tools for assembly.

by Ken Neubeck WB2AMU

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

An Hentenna plan for six meters band

Construction Details for 50MHz-Yagis in DK7ZB-Design

50 MHZ Moxon antenna based on the KG4JJH design with some slight modifications in the construction

The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.

Schematic of a regulated 0-24v 2A Power Supply

A long wire balun by ON6MU

This article presents a technical investigation into spurious emissions from the Yaesu FT-847 transceiver when operating on the 70MHz (4-meter) band. The author discovered significant problems with both factory "UK spec" and modified units. Spectrum analysis revealed that when transmitting at 70.2MHz, the radio produces numerous spurious signals, with the most prominent emission at 45.6MHz measuring only 3dB below the fundamental frequency. The study also documents poor power efficiency on 4m (10.3% at 30W output) compared to 6m operation (23.5% at 30W). Tests verified that jumper configurations had no effect on filter selection. The author warns that using these radios on 4m may violate license conditions due to excessive spurious emissions.

This program has been designed for packet communication with ISS (International Space Station), PCSat or 'compatible' satellites with ease... Ideal for any UI packet communication.

Halo antenna plan for the six meters band

Step by step instructions for setting up N1MM Logger to communicate with the TS-590S using the USB connection

Two types of multi-functional Home-brew 6/8Amps - 20 Ampere variable power supplies by ON6MU

A dipole for 2m, 4m, 6m band an hamdwritten note for a homemade vhf antenna that can be tuned across the VHF band

This free program displays the location of any locator on a map. It calaculates between two Maidenhead locators the distance (km and miles) azimuth longitude latitude Show the location, direction and distance as you move your mouse on a map! Graphical Locator Program, By ON6MU

G3WZT design for a bi-polar 600W Linear Power Amplifier for the 6M band.

ACOM 1000 modification uses electric band switching, such that both 6m and 4m operation can be maintained.

This homebrew six-meter linear amplifier started off life as a "junker" Alpha 76PA h.f. amplfier. Power output is 800W

A microphone preamplifier schematic for hand-helds by ON6MU

Ham homebrew, software, and ham info

The two linear amplifiers are ment for use with QRP SSB/CW/FM/AM transmitters on the amateur bands 15 and 17 meters can be powered from a 12 volt DC supply by ON6MU

Some rules of thumb for beginners, with a QRP approach, by James R. Duffey KK6MC/5

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.

5/8 vertical groundplane antenna for six meters band

ON6MU 4 A power supply using a BDX33

Review by Peter Bacon, G3ZSS

Paddles made from readily available materials, like double sided PC board material and cost almost nothing to build.

You can make your own 2-meter "rubber duckies" that will likely perform much better than many commercial units.

A PDF presentation of a home made moxon antenna for 50 MHz 70 MHz and 144 Mhz. The project is mainly out of surplus plastic Plumbing pipes and clips etc, and also details of how the dimensions were calculated.

6m (50Mhz) Long wire antenna There is another form of long wire antenna which provides uni-directional coverage and is easy to build. Description by Arnie Coro CO2KK

PTT and soundcard interface schematic by ON6MU

An interesting homebrewed gamma match feed for a Halo Antenna

A flex antenna working on 6m and 70cm by K0EMT

Class C tuned VHF power amplifier for the 6-meter band by ON6MU

This modification will allow the MkIIG to transmit on most of the frequencies that it receives on.

Are you suffering from TVI? Then why not try this filter for size. It is a three-stage high-pass filter that blocks low-frequency 50MHz signals while letting through UHF TV.

A SQ Loop antenna for 50 MHz, project include pictures and schematic diagram

MSHV is a free windows and linux multimode software that support weak signal digital modes like MSK144 MSKMS JTMS FSK441 FSK315 ISCAT JT6M FT8 FT4 JT65 PI4 amateur radio modes. MSHV features several interesting features including the Multi Answering Auto Seq Protocol, allowing multiple signal transmissions to be used during dx peditions.