Search results

Entities First Worked from Hong Kong on 50MHz

NARL homepage, the namibian amateur radio league

Associacao de Radioamadores de Amadora-Sintra Portugal

General station info and Paddle Museum (online display of keys and paddles)

lighthouses and lightships of ireland and northern ireland with arlhs reference numbers for all irish lights

Polish radio station

issued by the members of YO2KJI

Modifications for Retevis RT3 / Tytera MD-380 includes Hardware Modifications, Codeplugs, Software / Firmware Modifications.

Operating in a Single Operator Two Radios (SO2R) setup, especially with beverage antennas, often exposes the receiving radio's front-end to significant RF energy from the transmitting radio. This resource details a practical, homebrew receiver protection circuit designed to mitigate this risk. The core of the design involves a non-inductive 2W 22 Ohm carbon composition resistor in series with the RX antenna line, followed by two stacks of four fast-switching diodes (e.g., _1N914_) configured in opposite polarizations. This arrangement effectively clamps the incoming voltage to approximately 2.8 V peak-to-peak, safeguarding sensitive receiver input components. The series resistor plays a crucial role by absorbing excess power, preventing the diodes from exceeding their current ratings and potentially failing open, which would leave the receiver unprotected. The author, _N4KG_, measured up to 50 watts of coupled power between 80M slopers on the same tower, highlighting the necessity of such protection. The design is presented as a cost-effective solution to prevent damage to receiver input transformers, with the author noting successful protection of a receiver even after a resistor showed signs of overheating. This simple circuit can be integrated via a transverter plug, offering a robust defense against high RF input.

March/April 2010 will be QRV from March 16th till April 4th on IOTA NA-100, 6-80m - mainly in RTTY, PSK and SSB QSL via DL7AFS

DX pedition from Port Stanley, Falkland Islands (SA-002) calls : VP8BUG (digi-modes) and VP8BUH (SSB) QSL only via: manager EB7DX

AC7GZ/B is a converted Sharp CB-2460 Citizens Band transceiver operatin on 28.2118 MHz.

Liga Amadores Radio Sintra

This page is about the Ionosphere, how it was discovered, what it is, and what you can do with it.

A dynamic collection of high latitude geomagnetic data from 12 Canadian observatories

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

The RACES ARES Disaster Assistance Repeaters (RADAR) group was formed by a team of amateur radio operators dedicated to providing high quality repeater communications for amateurs involved in public service communications or response to emergency/disaster situations.

Amarteur Radio Society Of India, the national society, is issuing Worked Republic of India (WRI) Award to VU and Dx operators.

This article include a circuit that allows a cheap 0-1mA meter to be used as a micro-ammeter or a milli-voltmeter

W3FPR fixed level AF output fot the Elecraft K2

This award is open to all Amateurs and SWLs

How to add the YF-122CN 300 Hz CW filter or YAESU XF-119SN 2,3 Khz SSB filter in the Yaesu FT-857

The TRI-STATE emergency communications response team is dedicated to providing help to public service agencies with communications when normal communications are not working.

YU7EF EF0206 2m Band 6 Element Yagi Antenna project, provides 11.8 dbi gain

UK frequency list provide reference table to lister to Police scanner channels UHF VHF, Amateur Repeaters, Ambulance CB Radio CoastGuard Rescue, marine VHF, Military and more.

New Zealand Association of Radio Transmitters Auckland Branch 02

Details the history and cessation of the Amateur Radio Association of Bahrain (ARAB), operating under the callsign **A92C**. Established in 1970, ARAB functioned as the primary representative body for amateur radio enthusiasts within Bahrain for several decades. The organization facilitated various amateur radio activities and provided a central point of contact for local hams. The resource indicates that ARAB ceased operations due to unspecified circumstances. It explicitly states that the organization is no longer active, marking the end of its long-standing service to the Bahraini amateur radio community. Information regarding a newly formed society, open for membership, is provided, with contact details for Fawaz, **A92AA**, for further inquiries about the successor organization.

Taken from: Brief History of Amateur Radio in Calcutta-by Avinash Missra, VU2EM

Wakulla Springs, Florida U.S.A.

Alcatel Amateur Radio Association

The club was founded in 1987 when a group of ham operators hauled radio gear, antennas, and a generator to the island by boat to operate portable during ARRL Field Day

A.I.R.A. is chartered by the State of Illinois as a non-for-profit corporation and has been in existence over 21 years

Live webcam images, still pictures and movie clips over an HF SSB channel. NBTV (Narrow Band Television) is a technique with some similarity to SSTV, and some to conventional FSTV

Product information, resources, enhancements and links of the popular ICOM IC-756PRO III

These were some of the steps I took to setup my Allstar link node/server and some of the modifications that I did to it.

Exaustive review of the self-contained, top-performance HF/6m transceiver Icom IC-7700

The West Virginia State Amateur Radio Council (WVSARC) operates as a central coordinating entity for amateur radio interests throughout the state. Its primary function involves fostering cooperation among various local clubs and organizations, ensuring a unified voice for the amateur radio community within West Virginia. The council addresses matters pertinent to state-level amateur radio operations, including band plans, emergency communications preparedness, and regulatory issues affecting local hams. Historically, the WVSARC has played a role in organizing statewide events and providing a platform for information exchange among its member clubs. This structure helps to streamline efforts in areas such as public service events, disaster response drills, and the promotion of amateur radio to new licensees. The council's activities contribute to the overall health and growth of the hobby by facilitating communication and resource sharing across the diverse amateur radio landscape of West Virginia.

28.2665Mhz 10 meter beacon

Personal page with homebrewing articles by Y05OYR

Determining the characteristic impedance (Z) of an unknown coaxial cable, a common challenge for many radio amateurs, can be resolved with a straightforward method. The impedance of a coaxial cable is derived from its inductance and capacitance, and importantly, these values are independent of the cable's length or the operating frequency. This means that measuring a random length of cable, such as 20 meters, provides sufficient data for calculation. The core of this technique involves an LC-meter to obtain the inductance (L) in microHenries (uH) and capacitance (C) in microFarads (uF). The impedance is then calculated using the formula Z = L/C. For instance, a measurement yielding L=1.2uH and C=450pF (0.00045 uF) results in an impedance of 51.6 Ohms, closely matching **RG-58** specifications. Similarly, a TV coaxial cable with L=1.8uH and C=320pF (0.00032 uF) calculates to 75 Ohms. While the accuracy of this method, depending on the LC-meter's tolerance, is approximately 10%, it proves sufficiently precise for practical determination of unknown coaxial cable impedance, as noted by Makis, SV1BSX, who credits Cliff, K7RR, for the formula's dissemination.

Clarifies the intricate process of calibrating the _Elecraft K2_ dial, addressing common user challenges and lively discussions on the Elecraft reflector. Wilhelm, W3FPR, dissects the K2's PLL synthesizer design, chosen for its low phase noise, kit-friendly duplication, and cost-effective components. The resource emphasizes the critical role of the 4000.000 kHz reference oscillator's accuracy during CAL PLL, CAL FIL, and CAL FCTR functions, noting its dependence on temperature and crystal stability for optimal performance. Explaining the K2's frequency display, the document reveals it relies on microprocessor-driven look-up tables generated by CAL PLL for VFO values and CAL FIL for BFO values. In SSB and RTTY, these combine, while CW and CWr modes also factor in the sidetone pitch. The author details inherent limitations, such as the 10 Hz increment resolution of the dial and varying PLL step sizes—from 3 Hz on 160 meters to 10 Hz on 10 meters. BFO increments range from 20 to 35 Hz, collectively limiting practical dial accuracy to within **20 Hz** with diligent effort, or **30 Hz** for a slightly less demanding task. The guide outlines a four-step calibration procedure: setting the reference oscillator, running CAL PLL, running CAL FIL, and setting all BFOs. It highlights the _N6KR Method_ as a particularly easy and accurate approach, requiring only the K2 and a known frequency source like WWV for zero-beating, eliminating the need for external test equipment.

Analysis of flag receiving antennas using MININEC with focus on relation of size and atenna height by VE6WZ

Norfolk Island 6m DXpedition 25 March to 07 April 2012 VK9N/ZL1RS

Shiawassee Amateur Radio Club

The Western Washington Amateur Television Society (WWATS) is a group of amateur radio operators in the Puget Sound area with a common interest in amateur television

The YM2XBU Bilkent University Amateur Radio Club website details the club's activities and operational focus within the amateur radio community. It serves as the primary online presence for the university's ham radio enthusiasts, showcasing their involvement in various aspects of the hobby. The site provides insights into the club's station setup, operational modes, and participation in local and international amateur radio events. Club members engage in DXing, contesting, and educational initiatives, fostering practical skills in radio communication and electronics. The _YM2XBU_ club callsign is actively used for on-air operations, contributing to the global amateur radio network. Information regarding membership, meeting schedules, and contact details for _Kagan SIRDAR_ are available, facilitating engagement for students and faculty interested in amateur radio.

February 10-20, 2012 Winter DXpedition to Miquelon Island

This J-Pole is mounted on a fishing rod. The radiator L1 is an isolated copper-wire with a length of 281,5 cm while the quarter-wave matching sector L2 is made with 450-Ohm-Wireman-cable

D.I.CE diploma islas de chile.