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An excellent introduction to ham radio bands, which bands to use and when.

Australian amateur radio band plans in pdf format

Antenna experiment a Delta loop antenna for 7 Mhz band

3 band mobile antenna - 10m full size wave/4 whip - quick tilt-down system for 20 and 15 m loading coil change by IZ7DJR

Extension to an existing fan dipole originally modeled for 40 20 and 6 meters. This modification will add 80 15 and 10 meter bands.

Multi-band loft-mounted dipoles for 40, 20, 17, 15, and 10m

Part 2 You're now much closer to saying goodbye to your unwanted signal problems!

Interesting article on multiband fan dipoles. This article give an overview on designing this wire antenna, and planning a robust installation and proper feed line. Includes notes on setting up a commercial fan dipole antenna and on how diy your own.

Arduino Band decoder project available in KIT

This article explores the performance of an unloaded elevated vertical, base matching and feed line as a multi-band HF antenna system.

The 2.1 kHz wide European LF allocation between 135.7 and 137.8 kHz is detailed in this observed band plan, offering guidance for activity within this narrow segment. It specifically addresses the challenge of locating weak signals, such as those from Slow-CW stations, which can have bandwidths of only a few Hertz. The resource emphasizes the utility of precise frequency knowledge when operating with narrow DSP filters, like a 30 Hz filter for CW, to differentiate multiple stations within a very small band segment. The plan, though not officially recognized, provides practical orientation for operators, particularly those new to the _LF band_. It references a similar plan published by the _RSGB_ in the January 2000 issue of _RADCOM_, suggesting a community-driven approach to band organization. The content highlights the importance of spectral awareness, noting that multiple stations can occupy minimal bandwidth, a concept illustrated by spectrographic analysis.

A 5 band two element quad antenna working from 20 to 10 meters using hardware-store parts or modifying an existing commercial triband quad by KC6T

The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications.

This article explores the performance of an unloaded vertical as a multi-band HF antenna.

Single Coax Feed to Multi-Band Copper Cactus Antenna.

In this article, the author discusses the importance of good transformers for Beverages, especially for common-mode isolation. The author recommends #43 ferrite for the transformer, and provides the turns required for different core types. The author also recommends using lower permeability ferrites for better performance at lower frequencies.

Unlocking the full multiband potential of the 225 Ohm elementary radiator in a folded monopole, dipole-like or turnstile layout, by Francesco Errante

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

Definition of radio frequency bands, hf vhf uhf etc.

Homebrew a dual band vertical antenna

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.

In this project, you will make a simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator.

The G7FEK Multi-Band Nested Marconi Antenna, a small, efficient all-band antenna.

The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced.

Band Plan for HF Bands by IARU Region 1, effective 2014.

Kurzwellenbandplane der IARU Region 1 available in german and in english

The antenna is a VHF side is a 2m moxon, tuned on 145.825 MHz. The driven element of the moxon couples to a driven element for a 5 element 70cms Yagi, tuned on 436.5 MHz.

Triband DK7ZB VHF Yagi antenna for 6 m, 4 m and 2 m with a single feedpoint

Exagonal Beam antenna cover 20-17-15-10 meters By KE4NU

The original project of a dual band yagi antenna for 50 and 70 mhz, published on dubus 2/2007 by YU7EF

Package contain 1x yaesu vx-8r 1x sma dual section antenna 1x hf antenna lithium ion battery pack fnb-101li 1x battery charger nc-86c 1x connector unit

An excellent guide to homebrewing multi band end-fed antennas. The article, embed several drawings including diagrams and detailed pictures, illustrating the basic funcionality of end-fed antennas. The author gives some basic hints on how to build a half size antenna for 80 40 to 10 meters and a 6 meter to 40 meter configuration. It is also well described how to build the impedance transformer and the loading coils for lower bands.

To build a Band Decoder to drive our remote relays, we need to supply the band information from the rig to the decoder

probably the most simple and inexpensive antenna you could make for 23cm.

7 Band OCF Antenna project by W0HC

The SCOTIA Bandhopper a mobile multi-band vertical antenna

Optimizing the ZS6BKW antenna for full HF band coverage often requires specific modifications beyond its standard configuration. This resource details several enhancements, beginning with a simple series capacitor to improve 80m SWR, a technique W5DXP found effective for permanent installation due to its minimal impact on higher bands. Further improvements include a 10-inch parallel open stub for 10m resonance, shifting the frequency to 28.4 MHz with an SWR of approximately 1.8:1, a practical solution for Technician class operators. The document then explores a switchable matching section, adding or subtracting one foot of ladder line at the 1:1 choke-balun, which significantly impacts higher frequency bands and eliminates the need for a tuner on 17m. W5DXP's _AIM-4170D_ antenna analyzer measurements confirm these effects. More advanced modifications involve a parallel capacitor for further 80m SWR reduction, requiring remote switching for multi-band operation, and relay-switched parallel capacitors at specific points on the 450-ohm matching section to achieve low SWR on 60m, 30m, and 15m. These detailed steps, including _Smith chart_ analyses for the challenging bands, aim to transform the ZS6BKW into a truly all-HF-band antenna, reflecting W5DXP's practical experience in antenna tuning.

Build your own band decoder, for kenwood rigs too

An homemade fan dipole antenna for 20 30 40 meter bands, setup in a 15 meter wide garden. The longest leg for 40 meter is folded to fit in the 7.5 m

Lights on why 160 meters is so unpredictable and what is being done to reveal its secrets

A homemade tunable bandpass filter for all HF bands from 160m to 10m

As the sunspots return and DX propagation conditions to improve, the age old problem with QRM begins to show up on the amateur bands. Thif filter help you on improving reception

The N3UJJ multi band cage dipole antenna project thay can fit a small property

An Unorthodox Antenna, originally by W3AWH is considered a multi-band antenna suitable for fixed location use and as an easily deployable portable antenna for events such as Field Days.

The page, focuses on **TVRO** (Television Receive-Only) satellite systems, specifically addressing C-band and Ku-band reception. It covers technical aspects of digital video broadcasting, including **DVB** and MPEG-2 standards, relevant to satellite television enthusiasts. Content includes discussions on Digicipher 2 and 4DTV systems, which were prominent in North American satellite television at the time. The resource also references the South Scanner Satellite Services Chart (SSSSSC), a tool for identifying satellite transponders. While primarily about commercial satellite TV, the underlying principles of satellite signal reception and digital modulation have tangential relevance to amateur radio satellite operations.

Fill out the form to design a bandpass filter as described in the January 1985 issue of Ham Radio Magazine. These filters are generally limited to frequencies above 200 MHZ because their size is slightly longer than 1/4 wavelength

An efficient monoband end-fed half wave for 10m, 20m or any other HF band

Voltage baluns and choke (or current) baluns.

A simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator

Project of receive only filters optimized for minimal loss and very high rejection of frequencies below 75% of the filter center frequency by K1TTT