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The 2BCX Slim Jim by F.C. JUDD, G2BCX.

Comprehensive information page about bi-directional Beverages, including applications, construction details, and tips.

Listen to the Baltimore City Police radio feed, carries all of the police districts in Baltimore City (BPD)

Opinions on yaesu ft-450 equipment at radiobanter

Discussion group dedicated to those who enjoy monitoring radio frequencies in the VLF radio spectrum and slightly below the VLF spectrum (3-30 KHz).

A video demonstrating SMD board inside FT-897D to makes the two fans run only when temperature threshold is reached

Using bencher and Kenwood TS-50

This Z-Match is a link coupled all-band tuner. Two all band tank circuits cover 3-14mhz and 14-30mhz. The tank output links are selected with a very heavy duty SPDT rotary switch.

This project details the construction of a **full-sized 40-meter vertical antenna**, born from a renewed interest in 7 MHz operation and a desire for improved effectiveness over simple dipoles. The author, K5DKZ, initially focused on VHF experimentation, which provided an inventory of aluminum tubing and fiberglass spreaders for this endeavor. Before this vertical, K5DKZ utilized an 80/40 meter inverted-vee trap dipole and a 40-meter broadband dipole, but now primarily uses a pair of full-sized, phased, quarter-wave verticals spaced 35 feet apart for serious 40-meter work. The construction involves a base-heavy design for stability, using a 44.5-inch section of 1-1/4 inch steel TV mast driven into 1-3/8 inch aluminum tubing, insulated by a 105-inch section of Schedule 40 PVC pipe. The assembly reaches 31 feet, close to the 32 feet required for a quarter-wavelength on 40 meters, with fine-tuning achieved by winding wire onto a fiberglass spreader. The design is explicitly presented as a foundation for a two-element 40-meter Yagi beam, outlining modifications like substituting aluminum for steel in the base and using an inductive hairpin match for the driven element. The article also discusses tuning considerations for a large 40-meter beam, noting the 100 to 200 kHz upward frequency shift when raised, and suggesting methods for installation on a tower. The author emphasizes the cost-effectiveness and good performance of the monopole approach, especially when multiple verticals are needed.

Homemade hamstuf, mostly homebrew antennas in Dutch

A group of hams decided to make those wishes come true and founded the Straight Key Century Club - a/k/a SKCC.

dxing.com explains utc time and gmt conversions to local time

Yet another wiki page about the yaesu VX-2 hand-held transceiver.

How track and solve electrical interference from you computer

Istructions to use the IFD demodulator

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

Manufacturer of Radio Scanner receivers, scanner accessories, LCD Display modules and GINA data radio modems

VE3CVG 222 MHz (1.25m) 6 element plumber's delight yagi antenna

A project of a small antenna, just 50 cm for the 7 MHz band. An EH Antenna plan for the 40 meters band

Calculating HF helical whip antenna for mobile or portable operation

Los Angeles County Disaster Communications Service a public service organization using Amateur Radio

This calculator is designed to give resistor values for unbalanced T-pads, and for balanced H-pads.

Homebrew Light-weight Open-wire feedline for Portable Ops by N5ESE

Antartica 2006

Guide to ground mounting antennas, notes on efficiency, elevated installations, metal towers and masts, other mounting schemas, moble homes and rv, lightning protections, artiche by Bencher

SCARA is active in various events throughout the year. Helping as a public service with communications at various events has been a strong point for our club

Showcases the Del City Amateur Radio Club (W5DEL), an organization serving the amateur radio community in Del City, Oklahoma. The club facilitates local ham radio activities and provides a platform for members to connect. It emphasizes community engagement through various events and resources, supporting the interests of local operators. The club's online presence, while functional, appears to be a repurposed template, with some content not directly relevant to amateur radio. Members can access information on club dues, upcoming events, and community guidelines. The site mentions a focus on VoIP, suggesting an interest in **digital voice modes** and **internet-linked radio systems**. Although specific technical projects or operating achievements are not detailed, the club aims to foster camaraderie and provide a local point of contact for hams in the Del City area.

The NL Ham Radio Swap Shop is an online platform dedicated to connecting amateur radio operators in Newfoundland and Labrador with opportunities to buy, sell, and trade radio equipment. This service caters to both seasoned operators and newcomers, providing a space for exchanging second-hand gear, military radios, antique radios, and radio tubes. Users can browse listings, post their own items, and find unique equipment that may not be available in traditional retail outlets. In addition to facilitating transactions, the Swap Shop also serves as a community hub for local hams. It encourages networking among operators, sharing of knowledge, and collaboration on projects. Whether you are looking for a rare piece of equipment or simply want to declutter your shack, the NL Ham Radio Swap Shop is an essential resource for anyone involved in the amateur radio hobby in the region.

Sherwood Engineering Inc., based in Denver, Colorado, specializes in ham radio accessories and components. The company, located at 1268 South Ogden Street, offers a variety of products including filters, cooling kits, and audio switch boxes. Sherwood Engineering is known for its work with brands such as _Drake_, _Icom_, and Collins, providing components like 455 kHz mechanical and crystal filters. The company has also been involved in producing first-IF roofing filters and DSP protection filters. Sherwood Engineering has a history of over 45 years in the industry, though it has now retired from producing certain products like the SE-3 MK IV. Despite this, the company continues to provide technical resources and presentations on optimizing rig performance, with past events held at venues like the Dayton Contest University in 2014. The company operates Monday through Friday, from 9 a.m. to 5 p.m. Mountain Time, and accepts payments via PayPal, check, or money order. DXZone Focus: Denver | Filters | Icom

The Rock-Mite is a 40m CW kit offered by Small Wonder Labs . It features built-in keyer, direct conversion receiver with a crystal RF bandpass filter, 500 milliwatts of power, and switchable frequency offsets to work around QRM

This is an Android application used to remotely control several HAM radio Web SDR or any CAT enabled transceiver

A fractional bandwidth of up to 30:1 characterizes spiral antennas, making them highly effective across a very wide frequency range, often from 1 GHz to 30 GHz. The resource details two primary types: the **Log-Periodic Spiral Antenna** and the **Archimedean Spiral Antenna**, defining each with specific polar functions and illustrating their planar configurations. It explains that spiral antennas are typically circularly polarized, with a Half-Power Beamwidth (HPBW) of approximately 70-90 degrees, and a peak radiation direction perpendicular to the spiral plane. The content elaborates on critical design parameters affecting radiation, including the total length (outer radius) for lowest frequency, the flare rate ('a' constant) for optimal radiation versus capacitive behavior, the feed structure (often an infinite balun) for high-frequency operation, and the number of turns (typically 1.5 to 3 turns). It also discusses the theoretical impedance of 188 Ohms for Log-Periodic spirals, derived from Babinet's Principle, noting actual impedances are often 100-150 Ohms. The article presents a simple construction method for an Archimedean spiral, demonstrating VSWR and efficiency measurements. Measurements from a constructed spiral antenna show a VSWR that is fairly constant across the band, albeit with a mismatch loss of about 3 dB. The antenna efficiency remains around -5 dB (31.6%) across its operating range, indicating a decent wideband radiator despite opportunities for optimization.

Article on how use Genesys sowftware to design RF power amplifiers

Repair of a 756pro that was powering up always on TX due to some damage in the ACC1 connector area

This site is dedicated to mobile amateur radio operators, old and new alike. Whether you are into HF, or VHF operation, the information presented will increase your enjoyment of our great hobby.

Amateur Television activities in Pittsburgh,ATV operators and users, ATV links, ATV information

The design and feeding of driven elements for VHF/UHF Yagi antennas , modeling, observations and some case studies by Graham Daubney F/G8MBI

XLS file with technical specifications about ham radio transceivers

The Yaesu VX-5R, manufactured between 199x and 200x, offers a transmit frequency range covering 50-52 MHz, 144-146 MHz, and 430-440 MHz for European models, with US versions extending to 50-54 MHz, 144-148 MHz, and 430-450 MHz. Its receiver boasts an impressive wideband capability from 0.5 MHz to 999 MHz, with cellular frequencies blocked in some regions. The unit provides up to 5 watts RF output on 6 meters and 2 meters, and 4.5 watts on 70 centimeters, with selectable lower power settings down to 300 mW. This handheld transceiver utilizes a double conversion superheterodyne receiver system, featuring a 47.25 MHz first IF for FM and 45.8 MHz for WFM. Key specifications include a frequency stability of ±5 ppm across a wide temperature range and a current drain of 25-150 mA on receive. The VX-5R supports 220 regular memory channels with alpha tags, 3 home channels, and 10 NOAA weather channels, all stored in non-volatile EEPROM. Additional features include CTCSS/PL and DCS with tone search, ARS, ARTS, an internal voltmeter, and a Spectra-Scope. The device operates on a 7.2 VDC battery pack or 10-16 VDC external power, weighing 255 grams with dimensions of 58x88x27 mm. The VX-5R was also available as the metallic silver VX-5RS.

A large printable PDF file representing the world time zones. This map gives an overview of current local times around the world. If you ever asked yourself what time zone am i in, find your answer here.

It origionally included NYC Metro and Long Island, but has expanded to cover all of eastern New York as well. Future plans include expanding to cover all of New York state. The listings are a reflection of each repeater's true status, regardless of their coordination

This page allows you to calculate in the most accurate way high-Q inductor coils.

There are pages with info on the code, pictures of morse keys, a couple of downloadable tutor programs, mystery keys etc.

The Gizmotchy high performance horizontal and vertical beam antenna for 2/6/10/11 meter bands

Jason is a weaksignal communication program, especially tailored for LF work.

The Remote Control Antenna Switch consists of two circuit boards. The control unit and the remotely controlled switch

Useful tips for the use of automatic ATUs

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

Planning and modeling a special L antenna for Top Band

Chino, Montclair, Ontario, Rancho Cucamonga, Upland San Bernardino County police radio scanner