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Progress Report on VHF OFDM Modem submitted by John B. Stephensen, KD6OZH ARRL Pdf file

An SSB radio for the HF bands will be presented. Featuring 12 to 20 Watts of output power (depending on DC supply), full DDS frequency generation, covering 6 major frequency bands (1.8, 3.5, 7, 14, 21 and 28 MHz) within the short wave amateur radio spectrum. The rig also features colored LCD and front panel backlight.

A multiband trapped end-fed antenna can cover 20 30 40m bands. An option for portable sota operations were weight end simplicity are essential

Multi band Moxon Yagi Antenna for 10,15,20 meters band with just one feed line. Drawing and project with dimensions

On this page are designs for Dual Band 2M / 70cm antennas. All antennas are 50 ohm designed driver. These Yagis have a unique element called a Open Sleeve. 4 Element 5 element and 9 element Dual Band - 2M / 70cm antenna projects

The direct conversion receiver described consists of only a bandpass filter, mixer IC, VFO and audio filter. With only 22 parts, this simple circuit should take a few hours at the weekend to construct.

Demonstrating the construction of a short dipole antenna tailored for the 60 meter band, this resource provides detailed instructions for radio enthusiasts with limited space. The design incorporates inductive loading using two inductors (L1/L2) made from PVC tubes, allowing for effective operation on 5 MHz. The antenna consists of 12 meters of wire, divided into four sections, with specific dimensions and materials outlined for optimal performance. Results from users indicate that this antenna can significantly enhance DXing capabilities on the 60 meter band. Feedback from operators suggests that while the design is effective, adjustments may be necessary based on individual setups, such as coil diameter and wire gauge. Many users report successful construction and operation, with some experimenting with variations to improve resonance. The practical application of this antenna design has led to successful contacts and improved signal quality, making it a popular choice among 60 meter band operators.

Clean Up Your Signals with Band-Pass Filters

A few thoughts on Multi Band VHF Aerials by Peter Ward VK3ZAV

An EH Antenna for 14 MHz by EB3EMD based on an original project by F5SWN

This project is an interface box for the Yaesu FT-817 that includes a band output port, a computer serial interface, and a remote interface for the FL-7000 solid state power amplifiers.

6m/2m/70cm Yagi Antenna Built from Old TV Antenna This turned out to be a great little antenna. It works the 6 meter, 2 meter and 70 centimeter bands. You can use one common feedpoint or two seperate feedpoints depending on how you would like to connect this antenna to your transceiver.

21 28 and 50MHz three bands whip antenna by JA1HWO

Automatic and decoder project by sm3wmv

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

An almost invisible wire antenna for the 17 meters band

ON7YD narrowbands modes on 136 Khz

Will additional coax stubs improve Band Pass Filter performance?

These charts show the New Zealand bandplan

MW0JZE Manufacturer of the G3TXQ Broadband Hexagonal Beam - HexBeam Antennas

Performance of an unloaded ground mounted vertical as a multi-band HF antenna.

An automatic band decoder made into a nice enclosure with LED indicators for the chosen band

An easy to build dipole for 21 and 14 MHz with traps made by two T50-6 toroids cores mounted on a simple PCB foil

Changing band selector to a Kenwood TL-922 power amplifier by IW1PUR in italian

Tape measurement yagi. The longest part is 530 mm, easy fit to your backpack. Very easy and fast deploy. Great for SOTA and portable operation. Can be used in horizontal or vertical polarization. Based on DK7ZB design

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

A 600W 1.8 MHz to 54 MHz power linear amplifier made using rugged MRF300 transistors featuring output power between 580W and 750W depending on band, power supply: 48V, 18A typical, 20A max

50 to 54 MHz, the 6-meter band, presents unique propagation characteristics, often referred to as the "Magic Band" due to its sporadic E, tropospheric ducting, and F2 layer propagation potential. This resource specifically addresses repeater operations within this frequency range, focusing on the regional coordination efforts in British Columbia and Washington State. It highlights the standard -1.7 MHz transmitter offset commonly employed in these areas for 6-meter repeaters, a critical detail for proper station configuration. Amateur radio operators utilizing 6-meter repeaters in this region will find the mention of a typical 100 Hz CTCSS tone particularly useful. This tone, often called a _PL tone_ or _sub-audible tone_, is essential for accessing many repeaters and filtering out unwanted signals, ensuring clear communication. The resource also points to the _BC Amateur Radio Coordination Council_ (BCARCC) as the coordinating body, emphasizing the importance of coordinated frequency usage to prevent interference and maintain efficient band operations.

Fine tuning your Multiband Hustler Vertical

Homebrew 30 meter full quarter wave vertical antenna.

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

Review of the Retevis RT95 also marketed as Anytone AT-778UV dual band VHF UHF FM mobile radio transceiver

A shielded broadband (~200 MHz) active loop antenna offers more quiet and relatively less interference reception.

Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

VHF Broadcast Passband Filter (88 108 MHz) by DF9CY

A interesting guide to help get started with HF published at Essex Ham

The page provides detailed information on a compact two-element yagi antenna, also known as the Moxon rectangle, specifically designed for the 17 meters band. It includes construction details, evolution history, performance data, and comparison with a 1/2 wave dipole antenna.

This wire antenna for 40 and 20 meter band feature a good SWR. Horizontal side of the antenna is placed at two meters above the ground. Impedance of the antenna are depending by the height of the base from the ground and conditions of the ground

A review of all possible receiving antennas for top band 160 meters

This version of the broadband hexbeam is based on the work of Hunt G3TXQ, HB9MCZ, and Shoemaker K4KIO. EZNEC model is based on a wider element spacing than the version published in QST by K4KIO

Moxon is a rectangle shaped directional antenna, originally designed by Les Moxon G6XN. There are couple of advantages of using this antenna. It is small in size, Easy to mast, Balanced to 50 Ohms, Near 1:1 SWR, Excellent Front to Back (F/B) ratio, Large bandwidth

The construction principles for open-sleeve elements in antennas

5 Elements 12,5 Ohm Yagi with a 6m Boom

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

The RSGB Band Plan is normally published annually in the February edition of RadCom and additionally reviewed mid-year. It is derived from the IARU Region 1 Band Plan taking into account any proposed national variations or special amendments, which are considered necessary by the relevant spectrum manager.

Homebrew Amateur Radio 440Mhz Interdigital Bandpass Filter

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

Freeband modification for the Yaesu FT-100

Cushcraft X7 antenna design is based on Log periodic-Yagi and has real advantage over conventional multiband trapped tribanders.