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Distributors of specialty metals, electricial wire & cable, and high capacity magnet mounts for government and business. Stainless steel bars and rods for nuclear applications.

75m Mobile Texas Bugcatcher Loading Coil Measurements

Air conditioning soft copper tubes are perfect for loop construction. If you want to try a loop you must have an air variable capacitor or a vacuum variable capacitor. Article by PY1AHD

Pictures and description of a SteppIr vertical antenna setup in a small backyard using DX Engineering radial plates.

A 200 kHz bandwidth digital transmission system for image transfer in the Amateur Service is under development, specifically targeting VHF allocations. John B. Stephensen, KD6OZH, leads this project under an FCC Special Temporary Authority (STA) valid until September 10, 2006, authorizing emissions up to 200 kHz bandwidth in the 50.3-50.8 MHz segment. Current regulations typically limit bandwidths to 20 kHz on VHF amateur bands, making this STA crucial for testing wideband digital modes. The modem, a modified **OFDM** (Orthogonal Frequency Division Multiplexed) unit, was initially tested on the 70-cm band. It splits a high-rate data stream into multiple low-rate subcarriers to mitigate multipath echoes. The system uses a DCP-1 card with a Xilinx XC3S400 FPGA and Oki Semiconductor ML67Q5003 microcontroller. The transmitter, located at 36d 46m 30s N, 119d 46m 22s W, generates 150 WPEP into an 8 dBi gain vertical antenna, while the mobile receiver uses a Ham-stick. Three data formats for 50, 100, and 200 kHz channels are being tested, with encoded data rates of 96, 192, and 384 kbps. Verilog code for the VHF OFDM modem is 95% simulated, with modifications from the UHF version including increased filter coefficient precision and a change from Ungerboeck **TCM** to BICM for improved performance over fading paths. Final tests will involve one-way over-the-air measurements of bit error rates and coverage area.

PDF File of the Kenwood TM-710A user manual

The club was established in 1975 with the purpose to further the exchange of information and cooperation between members, to promote knowledge, to prepare for service in the community in time of disaster or need for emergency communications,

HB9BZA's LoTW users list, originally compiled since 2005 from DX-Cluster and user submissions, now primarily leverages the official ARRL full users list released on July 29th, 2017. This resource details 228,012 calls across 340 current DXCC entities, with the latest update noted on March 2, 2026. It offers various formats, including a full list, text versions, and breakdowns by country, providing valuable insights into LoTW participation for DXers. While the ARRL's official list with "last upload" dates diminished the original list's unique utility, HB9BZA's site continues to offer statistics and user counts by country, which remain of interest. The author, HB9BZA, expresses gratitude to contributors who helped maintain the list's accuracy over many years, achieving an impressive 96.4% match with the ARRL's data before the official release. Knowing which stations are LoTW active encourages more hams to join the system, demonstrating that even rare DXCC entities like Ducie Island or Heard Island can be confirmed quickly. For instance, HB9BZA recounts a 36-minute QSL confirmation for a 3A2MW contact. The list also integrates with the RXCLUS packet radio/telnet client, enhancing DXCC award tracking by identifying LoTW participants and utilizing upload dates for alarms.

St. Louis Repeater runs four repeaters in the St. Louis Metro Area, including two with autopatch capability.

Chesterfield Islands DXpedition 2000

The W3EDP is a 85 foot long wire and a 17 foot counterpoise. At N4KGL

An easy to build with a cheap HEMT FET Transistor Low noise preamplifier with FHX35LG based on JH0WJF design

This is a concept paper, not a constuction article. There are too many variables to propose a one size fits all design. However, this paper should give you the basic idea how to do it

The goal of detuning is not to avoid resonance, but rather to minimize re-radiation and/or current in the interfering structure.

colombian ham radio stations,radioaficionados colombianos,dx,qsl,photos,fotos

RigPix Database: Kenwood TS-50, pic and specifications, link to user manual

kv5r 2 meter antenna

Contesting resource pages by OH1NOA

Welcome to SW2A special contest station, with photos, logs and results

This resource provides a unique historical audio archive of 50 MHz DX contacts, documenting significant F2 and Es propagation events experienced by PA2S (formerly PA2HJS) since 1978. The collection includes recordings of beacons and two-way QSOs with stations across North America, South America, Asia, Australia, Europe, and Africa. Specific entries detail contacts with rare DX entities such as ZS6PW, VE1AVX, C5AEH, J52US, TR8CA, LU8MBL, VK8ZLX, and various Japanese stations, often noting the mode (SSB or CW) and propagation type. The archive also highlights challenging pile-up situations and frustrating near-misses during major openings. The recordings, initially in RealAudio format for solar cycles 21 and 22 and later in MP3 for cycle 23, offer a practical illustration of 6-meter band conditions over several solar cycles. The content allows hams to listen to actual signals from different continents, observing signal characteristics like typical TEP fading from 5H3RA or strong F2 backscatter from OZ1BVW. It provides a comparative perspective on propagation effectiveness between solar cycles, noting that cycle 23, while not as robust as previous cycles, still yielded interesting openings. The archive serves as a valuable educational tool for understanding real-world 50 MHz DXing and propagation phenomena.

Indiana's fastest growing hamfest! Saturday, November 29, 2003

Article explaining electronic network of low pass filters

Nice feature of the Baofeng UV5R family is that they support 6.25kHz tuning steps. That fact makes it possible to dial in the radio to use the exact PMR446 channel frequencies rather than a nearest fit which is the case in many other transceivers.

TSC International produces soft magnetic sheet steel, custom-stamped and heat-treated to achieve optimal electrical characteristics for applications such as motors, generators, linear power supplies, and ballasts. The company's manufacturing process focuses on precise material engineering to meet specific performance requirements in various electrical systems. They also specialize in soft magnetic core materials essential for transformers, chokes, and inductors. These core materials are utilized in power supplies, lighting ballasts, signal conditioning circuits, inverters, and battery chargers, providing critical magnetic properties for efficient energy conversion and signal integrity. Located at 39105 Magnetics Blvd, Wadsworth, IL 60083-0399, TSC International provides contact via sales@tscinternational.com or phone at +1 (0) 847 249 4900, facilitating direct inquiries regarding their magnetic component offerings.

The **136kHz Vertical Antenna** at G3YMC employs a Butternut HF2V structure, standing 10m tall. It integrates a 6.5mH loading coil to achieve resonance, with a matching transformer for impedance adjustment. The antenna's configuration includes top loading via a 12m horizontal wire, enhancing capacitive impedance. Initial measurements indicated a high impedance of around 300 ohms, necessitating a transformer for a 50-ohm match. Despite challenges with ground losses, the vertical antenna has shown improved performance in specific directions, filling nulls present in the previous loop antenna setup. The tuning remains broad, with variations due to environmental factors affecting the matching. Ongoing adjustments and comparisons with the loop antenna will continue to refine its effectiveness.

A 13 CM signal source project by W6PQL

Alexander The Great AWARD from Northern Greece Contest Team

NORAD Two-Line Element Sets, FAQ, and related informations.

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.

YAESU FT-1000MP Mark V ESSB Modifications pdf file

The IC-756, a Step Forward for HF and six metre DX by Frank van Dijk, PA3BFM

The latest info on the world of radio including:world,shortwave,pirate,digital,mw,lw news,links.

Yaesu VX-150, VX-170 BATTERY questions

30 Watt 50 MHz ham radio beacon de N6CA

Provides technology and solutions for the electronic test and measurement, optical, rf and microwave, wireless, wired, telecommunications. Make Frequency Counters, Antenna and spectrum analyzers, power meters, signal generators

Modeling compact 160 meter antennas, inverted L, half wave dipoles and linearly loaded dipole

New Zealand Amateur Radio 70, 32 & 23 cm (UHF) Repeaters

A small application that helps you to sort your outgoing QSL-card properly by UBA

A multiband HF Vee Beam antenna at VK5SW. If you're lucky enough to have the room, perhaps you may like to put up a multiband Vee Beam antenna for the HF bands.

Eham review for FT-1000d version

PACTOR mode radio modems and accessories, performance sailing electronics and innovative hard to find parts. Audio cables, packet cables, usb to serial converters

The G5RV junior Half Size antenna by kc8hps

Online calculator, Butterworth Bandstop (Notch) Filter Designer

How to design narrowband bandpass filters

Pmr, tetra ,ricetrasmittenti, ponti radio,motorola,icom,kenwood,pmr dealer in italy

Operating practice in english

ik3qar Logs on line of IOTA EU131 / IIA expeditions

G3SEK answers to some practical questions on builing the N2PK VNA Vector Network Analyser

This article describes a generalised unit for interfacing a transceiver's TTL/CMOS interface to RS-232.