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The Mobile-Portable Reflector serves as a dedicated discussion platform for amateur radio operators interested in mobile and portable operations. It facilitates the exchange of information and answers questions specifically related to operating amateur radio from vehicles, temporary field locations, or while walking. The platform is not intended for general amateur radio discussions; its scope is strictly limited to mobile-portable topics. Subscribers can access prior postings to review historical conversations and solutions. The list is administered by _dick at k7vc.com_ and operates on Mailman version _2.1.12_. Subscription requires email confirmation and offers optional privacy password protection, with an option to receive daily batched emails.

This wiki is intended to help identify radio signals through example sounds and waterfall images. Most signals are received and recorded using a software defined radio

This Radio Direction Finder Device Connects to an FM Receiver, Transceiver, or HT

The RadioFrequency Program is a professional Software dedicated to all HAM, SWL and Radio Listeners. Freeware. Included is a Text-CSV dBase Converter. Connection to the ICOM R8500 Receiver. Special Scanning Feature. Special Search Feature x large dBase.

80 metre superhet SSB receiver project

A simple free running oscillator oscillating at the receiver\'s IF (intermediate frequency) beats with the incoming signals in either CW or SSB and the resultant audio frequency goes to the AF amplifier.

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

A project with schematic to build a receiver for 80 meters band by VK1PK

TenTec Receiver RX 320 D Review by DF9CY

The 80 metre fox-or/test transmitter is a small low power transmitter which is designed to be used as an alignment aid for running up 80 metre foxhunt or ARDF receivers. It is also usable as a micro transmitter for fox-or-ing events.

A simple accessory for a satellite station, that allows using a 6 meter capable radio in conjunction with a typical S-band to 2 meter converter

Complete guide to receive weather satelite images with a RTL SDR dongle and free software

A full superhetrodyne SSB fox hunting receiver kit

What may be received from africa in north-west of france, french and english data

The idea makes use of a very simple direct conversion receiver on the band of interest.

Collection of several Crystal Radio receiver circuits with schematics diagrams and pictures

How to run an SDR Receiver on the Android Google Nexus 7 using SDR Touch App and an RTL-SDR dongle, review and costs by IW5EDI

Understanding the operational impact of Broadband over Power Line (BPL) on amateur radio communications is crucial for any radio amateur, especially given the potential for significant radio frequency interference (RFI). This ARRL tutorial delves into the technical aspects of BPL, explaining how the technology operates by transmitting data over existing electrical power lines, which can inadvertently radiate broadband noise across various amateur bands. My own field experience, particularly on the lower HF bands, has often involved tracking down noise sources that exhibit characteristics consistent with BPL emissions, making this a pertinent topic for maintaining clear receive conditions. The resource further details the specific FCC rules and regulations implemented to restrict BPL deployment. These regulations aim to protect licensed radio services, including amateur radio, from harmful interference. It outlines the technical standards and operational limitations imposed on BPL systems to minimize their impact on the electromagnetic spectrum, a critical aspect for contesters and DXers alike. For those engaged in RFI mitigation, the tutorial provides a foundational understanding of the regulatory framework that can be leveraged when addressing BPL-related interference issues. It serves as a valuable reference for hams seeking to comprehend the technical challenges and regulatory solutions surrounding this pervasive noise source.

An illustrated modification for the Icom IC-R20 receiver to locate and use the unfiltered audio.

Presents the VHFDX.EU web cluster, a specialized resource for VHF, UHF, and microwave DX spotting. It details the cluster's functionality, including real-time spot aggregation and a DXCluster Map interface for visualizing activity. The resource highlights its integration with the MMMonVHF backbone, ensuring a robust data flow for monitoring band openings and propagation events across higher frequencies. It also references reviews of the ON4KST and N0UK chat systems, which are frequently used in conjunction with VHF DX operations. The platform offers a mobile-optimized view for on-the-go access to DX spots, catering to portable and mobile operators. It further provides daily ES (Sporadic E) spot summaries, a critical feature for VHF operators tracking this specific propagation mode. The cluster serves as a central point for operators to share and receive information on rare grid squares, contest activity, and general band conditions above 50 MHz.

Kenwood TS-2000 Transmit / Receiver eSSB Modifications by N3GX

80 metre ceramix VXO with schematic and assembly instructions

Software defined radio products. Maker of AFEDRI SDR a direct sampling Software Defined Receiver by 4Z5LV

A nice tutorial and the basics of the software defined radio, SDR, and links of software defined radios to JTRS, and general SDR receiver technology.

This converter uses the popular NE602 mixer/oscillator chip and allows reception of signals below 500 kHz on a 3.5 – 4 MHz HF receiver

The _Sci.Electronics FAQ: Repair: RFI/EMI Info_ document, authored by Daniel 9V1ZV, provides a detailed analysis of computer-generated RFI/EMI, focusing on its impact on radio reception. It identifies common RFI sources such as CPU clock rates (e.g., 4.77 MHz to 80 MHz), video card oscillators (e.g., 14.316 MHz), and even keyboard microprocessors, all of which generate square-wave harmonics across HF and L-VHF regions. The resource outlines a systematic procedure for pinpointing RFI origins, including disconnecting peripherals and using a portable AM/SW receiver with a ferrite rod antenna to localize strong interference sources. The document categorizes RFI mitigation into shielding, filtering, and design problems, offering practical solutions for each. It recommends applying conductive sprays like _EMI-LAC_ or _EMV-LACK_ to plastic casings of radios, monitors, and CPUs to create effective Faraday cages, emphasizing proper grounding and avoiding short circuits. For filtering, the guide suggests using line filters, ferrite beads, and toroids on power and data lines, and small value capacitors (e.g., 0.01 uF for serial/parallel, 100 pF for video) to shunt RFI to ground. It also discusses the use of bandpass, high-pass, low-pass, and notch filters on the receiver front-end or antenna feed to combat specific in-band noise.

Designed to handle audio signal interfacing as well as transmit/receive switching Reviewed by Steve Ford, WB8IM

Bonito, butel wavecom and bogger products dealer. Accessories to decode encode and process radio communication transmissions for Radio Receivers, Transceivers and Scanners

A simple direct conversion receiver for 80m. The receiver covers 3.51 MHz - 3.60 MHz and 3.64MHz - 3.71 MHZ - CW and Phone portions by M0DGQ

Friis-It NF is the first iPhone OS based application that allows you to calculate noise figure, system sensitivity, and cascaded gain for an RF Receiver system

Build and run your own ADS-B receiver for 100 USD with a Raspberry Pi

Demonstrates a specialized DX cluster monitoring application, _DxWatcher_, designed for Windows environments. It processes DX spots received via Telnet/Internet, presenting them in a filtered table and a dynamic bandmap. The software integrates with transceivers, specifically the FT-2000, to read VFO frequency and enable one-click tuning to spotted stations. _DxWatcher_ version 1.0.3.0, released on 13 June 2020, includes minor bugfixes and improvements such as enhanced recovery from suspend mode. Key features include configurable bandmap position and size, automatic opening, and bolding of spots received within the last **10 minutes**. The application utilizes the standard _ctry.dat_ file for DXCC country analysis, allowing users to update it for current DXCC status. Source code, developed in C# with MS Visual Studio 2008, is freely available, encouraging modification and sharing while requesting retention of the original author's callsign.

Article on a QRSS receiver for 30 meters band

Commsaudit uk, i/q quadrature , hf receivers, rf, multicoupler, multicouplers, switch matrix, antenna matrices, masthead amplifier,, vhf receiver, uhf,

Elecraft KX2 tips and tweaks about how to improve your receive audio on the Elecraft transceiver

This windows software includes an easy to read display with features designed to give you accurate and enhanced control of your ICOM IC-R20 Communication Receiver. Commercial 35 USD.

Fixing notice subtle distortion on SSB receive audio on the Yaesu FT-1000D

BeaconSpot.uk provides an accurate, real-time picture of microwave and VHF/UHF beacons operating across Europe, alongside a worldwide listing of 6-meter beacons. The platform allows users to retrieve detailed data for individual beacons, facilitating in-depth analysis of signal characteristics and propagation paths. Interactive maps visualize beacon distribution by frequency band and display spot coverage for each station, offering a clear geographical overview of active beacons. The system integrates real-time DXCluster spots, sourced from contributors like Alain, ON4KST, and Pascal, F5LEN, and enables users to submit outgoing spots directly to the DXCluster. Beacon keepers can manage their beacon data, receive email alerts upon being spotted, and track their station's ODX (Outstanding DX) records. For every received spot, the distance to the beacon is automatically calculated and displayed, aiding propagation studies.

Christoph Petermann DF9CY DRM demonstration receiver project including Circuit Diagram and component list

IK2PII describe here a simple direct conversion receiver, thinked for QRSS and DFCW communications, as companion of ARGO or SPECTRAN programs.

Receiver performance test of the Icom IC-7610 transceiver done by Rob Sherwood

This walkie is sold without the wide band receiver enabled, this is, only 144 and 432 MHz band

Display and Send Hellschreiber On Your iPhone and iPad - iPhone / iPad app to send and receive Hellschreiber

This application allows Ham Radio Operator to browse and search his LoTW QSL confirmations on his handheld device, and receive notifications when new QSL confirmations appear on Logbook of the World.

This project is a Software Defined Radio Receiver. It has a frequency range of 24MHz 1.2GHz. It can demodulate AM, FM, USB, LSB with selectable bandwidths of 600, 2400, 2800, 3200 and 6400Hz. Using a simple RTL-SDR Dongle and Raspberry Pi 3 computer using GNU RADIO

An interesting article on grounding and receiver noise

A page dedicated to the Heathkit GR-81 Regenerative Receiver

Homebrewing a vhf bicone antenna with 8 clothes hangers and 4 feet of Sch40 non-metallic rigid conduit

A searchable database of online websdr receivers, lists OpenWebRX, KiWi SDR and WebSDR from all over the world, providing a web interface to search and filter links to websdr

TYT Electronics boasts of 15-year experience in two-way radio manufacture. Produce DMR transceivers, handhelds, receivers and mobile radios, analog amateur radio and commercial VHF transceivers