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EF155A1 21 MHz monobander antenna by YU7EF

The circuit is based on two AD8307 log amplifiers, which are connected to the forward and reflected ports on a directional coupler

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

Every ham needs an RF power meter. Here is a high performance unit to build at home.

January 1955 QST article by W5DQV about constructing a Cubical Quad antenna for 14MHz PDF File

Presents the DBO274 Citizen Band mailbox, a digital communication hub accessible via HTTP and Telnet, specifically catering to **CB radio** enthusiasts in Germany. This resource outlines its functionality for Packet and other digital emissions on the 11-meter band, a segment often overlooked by traditional amateur radio operators but vital for CB users seeking advanced communication methods. The author, DH8YMB, provides insights into its operation, reflecting practical experience with digital modes in the CB spectrum. The DBO274 serves as a bridge, enabling users to exchange messages and data packets, extending the reach and utility of standard CB transceivers. It represents a localized digital infrastructure, demonstrating how the 27 MHz band can support more than just voice contacts, incorporating elements of early internet-like communication within the CB community. This setup highlights the enduring innovation within the CB realm, adapting technologies like Packet Radio for a different user base. It underscores the versatility of radio communication, even on less conventional bands, for those interested in digital data exchange beyond the typical amateur allocations.

Backpacking, boating or mountaintopping ? Invest your time and pack this novel directional gain antenna on your next expedition

This 40 meter Inverted V antenna was tested and tuned at a height of 35 feet and proved excellent results. The ends of the antenna are about 11 feet above the ground. Article and video available

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

CB Radio and 10 meter Radio reviews & mods blog. Most articles are in Japanese

5/8 vertical groundplane antenna for six meters band

3 Element reversable quad antenna for 40 meters band

The circuit described below will substantially reduce or completely eliminate interference from almost any local source whilst leaving the wanted signal relatively unaffected, even though it may be on the same frequencey by TREVOR, G3ZYY

Operating on 160 meters from a city lot is always a challenge. Here's how K9YC does it.

A 40/80 meters dipole made with two loading coils based on a project by IK1ZOY

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

Article on a 2 and 6 meters halo antennas that does not require a mast has a very low part count and can easily be built with a minimum of tools.

2 meter kilowatt linear amplifier

3d parts printed to build an EZ-Lindenblad 2 Meters LEO Sat antenna as designed from Anthony Monteiro

A simple center-fed dipole made just with a thin-wall PVC pipe, aluminum tape, and RG-8X coax

A solutiom for the Ameritron AL-811(H) RF power amplifier, burnt panel meter lights. A common failure with the Ameritron AL-811 and similar amplifiers is that the panel meter lights burn out prematurely. These bulbs are usually integrated into the actual panel meter. The solution for this is to provide the meter backlighting with LEDs.

A home made yagi antenna featuring 6db forward gain and 22 Db front back

The digital wattmeter project was created for the purpose of measuring power in the range of 300nw to 30w.

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

A project of a bobtail-curtain antenna for 10 MHz

How to adjust your SWR on your radio and why.

RF Power Meter using for reading a standard Digital Voltmeter by Iulian Rosu, YO3DAC / VA3IUL

PCB for the DJ9BV Power Meter taken from DUBUS 3/87

Presents the construction of a 6-meter (50 MHz) Moxon wire beam antenna, detailing the use of #14 AWG THNN stranded wire and a treated wood frame. It covers the assembly of a galvanized pipe mast, emphasizing the use of pipe sleeves for joint reinforcement over threaded couplers to prevent breakage during raising and lowering operations. The resource also describes the integration of a 1:1 current balun, rated for 50-54 MHz, and the use of RG-8X coax for the transmission line, recommending low-loss alternatives like Belden 9913-7F. Further, it outlines a manual rotation mechanism using pipe hanger clamps and carriage bolts for true North orientation, incorporating magnetic declination calculations from NOAA. The antenna's performance is discussed, noting good gain and take-off angle, with SWR tuning facilitated by a Palstar AT-500 manual tuner. An EZNEC+ 5.054 model for the antenna is available for download, alongside predicted radiation patterns and SWR curves, compared with actual AIM-4170C measurements.

A 2-metre Quad antenna project by K6WXA in PDF file

An 80 meter band vertical loop antenna setup

This antenna analyzer measures complex impedance over the 1.6 - 33 MHz HF spectrum

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses by VK4MDX

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

The YB7ZGP Pamaton Repeater operates on a frequency of 146.76 MHz, serving the Martapura District in Banjar, South Kalimantan, Indonesia. This VHF repeater provides local communication infrastructure for amateur radio operators in the region. The repeater's operation is managed by Syah Riyan, indicating a local amateur radio enthusiast or group maintains the station. Repeaters like YB7ZGP are critical for extending the range of VHF/UHF communications, allowing handheld and mobile transceivers to communicate over greater distances than line-of-sight. The 146.76 MHz frequency falls within the 2-meter band, a popular segment for local and regional amateur radio traffic, often utilized for emergency communications and general ragchewing. Information regarding the _Pamaton Repeater_ is presented on a blog platform, suggesting a community-driven effort to disseminate details about this local amateur radio asset.

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.

The resource details the construction of a 3-element Yagi antenna specifically designed for the 6-meter band, providing coverage across 50-54 MHz. This antenna design, originally featured in _QST_ August 2007, emphasizes a short boom configuration while maintaining a wideband response. Key specifications include a 50 Ohm SWR of less than 2:1 across the entire band, achieved through specific element lengths and spacing. The design utilizes aluminum tubing for elements and boom, with detailed dimensions provided for the driven element, director, and reflector. Performance characteristics indicate a forward gain of approximately 7.5 dBi and a front-to-back ratio of 18 dB at 50.125 MHz, according to _NEC2_ modeling. The antenna's compact size, with a boom length of 1.83 meters (6 feet), makes it suitable for portable operations or installations with limited space. Construction involves standard amateur radio workshop tools and materials, with a gamma match for impedance transformation to 50 Ohms. The design prioritizes ease of construction and repeatable performance for the 6-meter enthusiast.

Plans and hex code for an RF wattmeter based on an Analog Devices AD8307 log amplifier.

Homebrew a 2 meter square dipole antenna

A 27-28 Mhz quad loop antenna by Bernard Mourot F6BCU in french

Details the Northern Amateur Relay Council of California (NARCC) as the regional coordinating body for amateur radio repeaters operating on the 10-meter band and above. It outlines NARCC's function in managing frequency allocations to minimize interference and ensure efficient spectrum use across Northern California. The resource specifies that NARCC operates in cooperation with the FCC and ARRL, indicating its recognized authority within the amateur radio community. The organization's role centers on repeater coordination, a critical aspect of VHF/UHF operations where multiple stations share limited frequency segments. It highlights the support received from local amateur radio operators, underscoring a community-driven approach to spectrum management. The site serves as a primary reference for hams seeking to establish or operate repeaters within the designated service area. NARCC's activities directly impact the operational landscape for _VHF_ and _UHF_ enthusiasts, providing essential guidelines and coordinated frequencies. This ensures orderly communication and prevents conflicts, particularly in densely populated areas of Northern California.

Homebrewed handheld RF powermeters for various sensors by DL5NEG

A nice loop antenna project for 28 MHz with schematic diagram, construction details and a complete video instruction

SMIRK club news, DX information, content details, and forum for 6 meter operation enthusiasts.

6-Meter Solid-State 100W Linear Amplifier complete documentation German and English

MS Word document with FT-1000 S meter characteristics

KJ4WLH homemade dipole for 50 Mhz

The DL4MEA Power Meter

Presents a QRP AM/CW transmitter project specifically designed for the 10-meter band, utilizing a crystal oscillator and a collector-modulated AM oscillator. The design employs a 2N2219(A) transistor in a Colpitts configuration, generating 100 to 350 mW of RF output power depending on the 9-18 Volt supply voltage and modulation depth. Frequency stability is maintained by a 28 MHz crystal, with fine-tuning possible via a Ct1 trimmer capacitor for approximately 1 kHz adjustment. The resource details the RF oscillator stage, implemented with a 2N2219 NPN transistor, emphasizing frequency stability and low power dissipation. It also covers the amplitude modulation stage, managed by a 2N2905 PNP transistor, which impresses audio information onto the carrier. Selective components (C3, C4, C7, C5) enhance voice frequencies within a +/- 5 kHz bandwidth, and modulation depth is controlled by R2 and R3. The project includes a 3-element L-type narrow bandpass filter (Ct3, L3, C10) to suppress harmonics and ensure a clean output signal. The project provides a complete schematic diagram, a comprehensive parts list including specific capacitor, resistor, and inductor values, and construction notes for the coils (L1, L2, L3). It also offers practical advice on enclosure requirements, suggesting an all-metal case or a PVC box with graphite paint for RF shielding. Operational parameters such as current draw (27mA@9V to 45mA@16V) and input impedance (50 Ohms) are specified, alongside guidance on antenna matching and the importance of a valid amateur radio license for 10-meter band operation.

The 1721 HF Roundtable Group meets nightly on 7.261 + - QRM. Just a big ham radio family. Informal QSO'S in a rountable fashion.