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Beacons on 4 meter band

Cheap but effective multiband quad antenna covering the entire horizon on 10-12-15-17-20m bands.

Amateur projects to investigate radiowave propagation - G3PLX's chirp project, ionosonde database, and more

Connecting a Yaesu MD-100 dynamic desktop mic to the Kenwood TS-850

Refractive Index maps forecast for Europe

Operated by the amateur radio club RK3AWL, Zelenograd Russia

A Yagi-Mag antenna for the 4 meters band with NEC and MMANA files plans and pictures

Forum post on differences between the Acom 1010 (single 4CX800) and Acom 1011 (Two 4CX250B)

A forum thread about tuning with the Kenwood TL-922 TL-922A Power amplifier

Mods.dk modifications for the Kenwood TS-690

Jose B Rivera, N2LRB, shares his initial experiences with the Icom IC-7300, recounting a shift from skepticism to appreciation for the transceiver. He details how the radio's impressive Sherwood Engineering test results, ranking it #12, significantly influenced his decision, especially considering its competitive price point against higher-end options like the Elecraft K3s. The review highlights the IC-7300's strong receive capabilities, a key factor in N2LRB's purchasing decision, and notes the advantages of its SDR architecture for future updates. He describes the straightforward setup process, from unboxing and connecting PowerPole connectors to making a first contact with N0HQ, a special event station. N2LRB expresses satisfaction with the radio's clear audio and ease of tuning, even if the pan-adapter's utility for his operating style remains to be fully explored. He concludes that the IC-7300 offers exceptional value, providing SDR features and receive performance comparable to more expensive rigs at half the cost.

Test equipment and ham radio related manuals

How much better is an N over SO-239 at VHF/UHF, a discussion topic at eham

A cavity filter, often a critical component in _duplexer_ designs, functions as a sharply tuned resonant circuit, allowing only specific frequencies to pass while attenuating others. These filters are essential for maintaining signal integrity in environments where multiple transmitters and receivers operate simultaneously on closely spaced frequencies, such as in repeater stations. The article details how these filters, sometimes referred to as _notch filters_, achieve high Q factors, which are crucial for their performance. Understanding the principles of cavity filters is fundamental for any amateur radio operator involved in repeater operation or designing custom RF front-ends. The discussion covers the basic circuitry and operational characteristics that enable these devices to provide significant isolation, often achieving **-80 dB** or more between transmit and receive paths. This level of isolation is vital for preventing receiver desensitization and intermodulation distortion. Properly tuned cavity filters ensure that a repeater can transmit and receive simultaneously on different frequencies without self-interference, a common challenge in VHF/UHF operations.

Gridmaker takes your ADIF-file and searches for all the grids on the specified band. It then makes files for use in DXAtlas

Ham radio classifieds in Austria

Articles about TM-D710 radio modifications at Mods.dk

This is a popular discussion forum for ham radio operators

ICNIRPcalc allows you to calculate safety distances for many know amateur radio antennas with respect to ICNIRP limits by DL9KCE

Article on Yagi and Log periodic antennas by Tom, K1JJ

Articles and review on the Yaesu FT 817 by OZ9AEC

Introduction to shortwave propagation

Descriptions, summaries,and tutorials about electronic circuits and electronic circuit design including amplifiers, attenuators, logic, transistor, operational amplifiers and much more

A complete guido to 4 Metres band for beginners

New PA stage for good old Atlas 350XL HF transceiver

The I2YSB DXpedition Team presents a collection of videos documenting their past DXpedition activities. These visual records offer insights into the operational aspects, equipment deployed, and environmental conditions encountered during various DXpedition events. The resource also contains a specific announcement regarding the cancellation of the planned Ghana AF-084 DXpedition, originally scheduled for April. It further details the refund process for sponsors who had contributed donations for the cancelled operation. The content serves as an archive of DXpedition experiences, showcasing the efforts involved in activating rare or challenging entities. It provides a historical perspective on the team's operations and logistical considerations. The site also functions as a communication channel for important updates concerning future or cancelled DXpedition plans, directly addressing the amateur radio community interested in their activities.

Official page of the IARU High Speed Telegraphy Championships

How to handle feedline radiation issues

A complete list of resources for the Kenwood TS-850 mantained by TK5EP

How to limit unwanted harmonics from your raspberry Pi radio transmitter by introducing filters.

Visual Wais is a free HAM (Amateur Radio) software to manage WAIS (Worked All Italian Squares) award. With few clicks, it allows the complete award management, from QSO insertion to endorsement requests.

A resource page for Kendoowd TS-850 HF transceiver

Harleys, Astronomy, HAM Radio, and other stuff

The Pro 95 is a dual trunking handheld scanner designed by GRE and sold by Radio Shack

Setting up a Live Broadcast on the internet using windows pc and in internet connection

An extensive document about Morse Code in amateur radio edited by W5ALT

A comparison of commercial 4m verticals by by Ian Hogan G6TGO

A Web forum dedicated to HF underground and in particular to Shortwave Pirate Radio Forums and Spy Numbers listenings

Microwave band plan - frequancy assigned to ham radio service

Do you want to see how your FT8 signals are being received in the other parts of the globe?

RF is causing strange issues on the touch sensor buttons, controlling inputs, volume, channels on Samsung LCD TV. Solution is to disable front touch panel.

Togo DXpedition 5V7TT 10th-23rd October 2010

Antuino is an accurate instrument that can be used in the field to measure SWR, field strength, modulation, etc. In the lab, it can be used to sweep filters, measure gain, distortion, frequency response, etc. It works upto 150 Mhz. On the third harmonic, it is usable on 435 Mhz band as well (with reduced sensitivity).

Ham or amateur radio is a fascinating hobby for all

The National Digital Link Cisar CisarNet Project

Die kontestgruppe dk0bn

A multi sked portal offering sked spots grouped by CFO CW Practice CW Academy Development Digital FISTS Down Under FISTS Scouting LoTW/eQSL MARS NAQCC NRR Other Images POTA Ragchew Satellite SKCC TBDXC VHF/UHF

Resource page for the ICOM IC-R75 at RadioReference

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency. This article explains a method using a RF signal generator at +10dBm output into the coaxial trap.