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Demonstrates a range of specialized radio frequency equipment and consulting services for amateur and professional applications. The offerings include _Vector-Finder_ direction finding antennas, various test equipment such as _gate dip meters_ and RF sniffers, and communications receiving adjuncts. Additionally, the company produces satellite antennas for weather satellite reception, voice amplification devices like the _Flex-Mike_, and custom prototype circuit boards. The company's product line addresses needs for precise RF measurement, signal detection, and specialized antenna systems, particularly for direction finding and satellite communications. Their historical association with National Radio (HRO) suggests a legacy in radio technology. The site also highlights a subsidiary, Sierra Mountain Products, which offers outdoor recreational gear, indicating a diversification beyond core RF manufacturing.

Two coupled PAs with each 2 times 2C39 deliver around 400W RF.

This test circuit is easy to duplicate, and demonstrates the extreme voltages that appear in an amplifier when the load is improper for the amount of drive power applied.

100 W output RF amplifier for 10 meter band project by W4NFR

Design and manufacture application specific microwave and RF amplifiers, upconverters, downconverters and multifunction assemblies.

A complete restoration of a Heathkit SB-200 HF power amplifier

Understanding Solid State Linear Amplifiers

PEP RF output power measurement, and examples RF output power measurements

How to connect and key Power Amplifiers to Kenwood TS 590 or TS 990. How to home made custom Remote cable to key power amplifiers by JG1VGX

Sell all types of obstruction lighting. Lighting for your ham radio antenna tower. Genesis Lamp stocks a wide variety of replacement bulbs and specialty replacement light bulbs including: airport lighting and airport light bulbs, incandescent light bulbs and more

Download the official IC-705 RF direct sampling VHF, UHF, HF, D-Star all mode 10W QRP portable transceiver. Pre-release information in a PDF file all in English.

Observing extremely slow CW (QRSS) signals requires specialized reception and display techniques, often involving long-term signal integration to make faint traces visible. This resource compiles numerous screenshots from active QRSS grabbers globally, providing a visual record of signal propagation and operational activity on specific amateur bands. Each entry typically includes the callsign of the grabber station, its grid square, and often the band being monitored, such as 40 meters or 30 meters. The compendium presents a diverse array of grabber outputs, with examples from North America, Asia-Pacific, and Europe. Notable stations featured include _W5GB_ at New Mexico State University, _VE1VDM_ in Canada, and _I2NDT_ (the author's own grabber). The collection illustrates the unique visual signatures of QRSS transmissions, where signals appear as faint lines or patterns against a noise floor, often over extended periods. The utility of such a collection lies in its ability to demonstrate real-world QRSS signal characteristics and the geographical distribution of active grabber sites. It serves as a historical snapshot of QRSS activity, allowing operators to compare signal traces and observe propagation phenomena across different continents.

Who needs a GaAsFET? Tuning, constructions and Packaging by Paul Wade

Presents the official web presence for the Mike Charlie DX Group, identified as 14MC, a CB radio association operating from Lyon, France. The resource details the group's activities, which include engagement in digital communication modes such as packet radio, PSK31, SSTV, FSSTV, and MT63, indicating a focus beyond traditional AM/SSB CB operations. It provides contact information, including the group's email address and a specific callsign, 14MC17, associated with the publisher. The site offers historical context through its copyright dates of 2000-2001 and a last update timestamp of October 6, 2004, reflecting its operational period. It lists key identifiers like "14MC01" and "14MC17," suggesting individual or station callsigns within the group structure. The content emphasizes the group's identity as a "cibiste lyonnaise" association. The resource serves as a digital archive for the 14MC group, documenting its existence and operational interests in CB radio and digital modes. It provides specific keywords like "14," "cb," "14MC," "packet," "psk31," "sstv," "FSSTV," "MT63," "Lyon," "CIBI," "radio," and "Micro-contact," which collectively define the group's technical scope and geographic base.

Homebrew Tubes/LDMOS amplifiers, Antenna, accessories, adventures in 9Q, DX, UN missions, Contests, and more.

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

Windows signal function generator sotfware, offers 4 main channels, 4 modulators, 1 measurement generator, 1 frequency standard generator, Amplitude, phase and frequency modulation, can generates real band-limited signals

This project is an interface box for the Yaesu FT-817 that includes a band output port, a computer serial interface, and a remote interface for the FL-7000 solid state power amplifiers.

HobbyPCB.com provides quality products and boards for amateur radio including the popular HARDROCK 50 amplifier

Improper tank adjustment and excessive drive are equally harmful to component life, and either can create splatter

Ham radio, Mir contact samples in Real audio, packet and some links

A recognized organization of Murray State University providing programs and activities that promote interest in Amateur Radio within the campus and community.

This circuit will let you look at the signal and frequency output of your transceiver.

Projects you can build, an amplified shaped sine-wave oscillator

1500 watts of RF output on the 70cm band requires robust amplifier design, a challenge addressed by this project featuring the GS-23b / 4CX1600U Svetlana tube. The resource details the construction of a high-power UHF amplifier, providing insights into component selection and layout necessary for stable operation at these frequencies and power levels.

Constructing a high-power 70cm solid-state amplifier presents unique challenges, particularly when aiming for 500 watts output using modern LDMOS devices. This resource details the author's experience building a 70cm amplifier based on a _Freescale MRFE6VP5600H_ transistor, initially from an RFHAM kit. It meticulously outlines the necessary modifications to achieve advertised performance, including optimizing input and output matching, correcting bias circuitry, and ensuring proper output balun connections for stability. The author shares specific adjustments, such as trimming the prototyping board for better transistor fit, drilling additional mounting holes for improved heat sinking, and replacing original matching capacitors with a single _20pf MIN02 metal mica_ for superior output. A critical fix involved jumpering gate decoupling pads to balance the push-pull transistor halves, which increased output to 580W and improved IMD. The resource also highlights a crucial correction to the output balun connection, initially reversed in the _Dubus_ article schematic, which resolved intermittent stability issues. Test results are provided, showing input power, output power, and drain current at 50V, demonstrating the amplifier's performance after modifications. This practical account offers valuable insights for hams undertaking similar high-power UHF amplifier projects, especially those working with LDMOS devices and kit-based constructions.

A 50MHz kW Amplifier by Goran Grubishic, 9A6C

Collection of Kenwood TL-922 linear amplifier modifications

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.

A well documented PDF document containing picture sequence taked during the repair of an Icom IC-7700 HF transceiver power amplifier module

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

Techni-Tool is a distributor of electronic production tools, oscilloscopes, multimeters, power supplies, cases, tool kits, cutters, wrenches, crimpers, solder desolder stations, BGA, microscopes, lamps, static control, workstations, chairs, torque screwdrivers, tweezers, dusters, chemicals.

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.

Excellent article and guide to choose the best RF power amplifier that fit your needs by ON4SKY

A simple charger designed for charging 12 V sealed lead acid batteries, used by radio amateurs for portable operation Amp-Hr Class used by radio amateurs for portable/emergency operation.

A collection of modifications and improvements to the Ameritron ALS-600 ham radio RF power amplifier

An amplifier made using an old HT-41 Hallicrafters Amplifier and adding the 160 meters band By W4NFR

eHam reviews for the Ameritron AL-811 linear amplifier

This video will provide a foundation for understanding how power amplifier circuits work. If you are new to High Frequency Power Amplifier Circuit Design, this is the place to start.

Home Brew a 4-1000A RF power amplifier project by W4NFR

Operating the _Icom IC-746_ HF/VHF transceiver often presents specific technical questions, and this resource compiles a comprehensive Frequently Asked Questions (FAQ) document in an ASCII text format. It details common inquiries and solutions related to the rig's functionality, accessories, and potential modifications. The content is structured into distinct sections addressing general information, power supplies, antennas, microphones, keyers, amplifiers, TNC integration, and optional IF filters. The FAQ provides practical guidance on topics such as configuring the internal automatic antenna tuning unit (ATU), selecting appropriate power supplies, and understanding microphone pin-outs. It also delves into advanced subjects like computer control via CI-V, wiring for PSK31 operation, and troubleshooting common issues like low S-meter readings on 2m FM or loose tuning shafts. Specific questions cover the installation of optional IF filters, comparing Inrad versus Icom filters, and optimizing filter combinations for various modes. Furthermore, the document outlines various hardware and firmware modifications, including those for increasing monitor volume, replacing LCD driver transistors, and implementing a "poor man's TCXO." It even touches upon untested modifications, such as replacing PIN diodes in the demodulator. The FAQ also lists manual errata and discrepancies, offering a robust knowledge base for IC-746 owners seeking to optimize their station or resolve operational challenges.

1.2 to 30 Volts 1.5 Amps Power Supply

EB5AGV Workbench: Yaesu FL-2100B amplifier restoration

ARRL special service club

A 160W linear amplifier for 4 meters band based on GI0GDP

Southeast New Hampshire W1SRA / 147.000Mhz / Negative Offset / 100.0 PL Tone Welcome to the Sunday Night Net each Sunday evening at 8:00 PM.

This resource, a blog from the Penang Amateur Radio Club (PARC), offers insights into various aspects of amateur radio in Malaysia. One post details monitoring Automatic Terminal Information Service (ATIS) on the 2m band, providing specific frequencies like 122.750 MHz AM for Butterworth and 126.400 MHz AM for Penang, along with sample aviation weather and operational data. Another entry critiques the lengthy and costly process of obtaining an amateur radio license in Malaysia, contrasting it with the more streamlined FCC licensing system in the United States, citing a 1-year wait and RM 414 (USD 125) for 10 years in Malaysia versus 3 weeks and USD 14 for 10 years in the US. The blog also covers internal club matters, such as the 2007 Annual General Meeting (AGM) attendance and council elections, highlighting member dissatisfaction with outdated newsletters and a call for "reformasi." Additionally, it presents local phonetic alphabets in Bahasa Malaysia and Chinese, and discusses monitoring AM broadcast bands for international stations like Voice of America on 1575 kHz and Zhong Yang Ren Min Guang Bo Dian Tai on 1134 kHz, offering alternatives to local 2m repeater chatter. The author, "firstclass," shares personal observations and criticisms regarding the Malaysian ham radio landscape.

This article describes an alternative to water as the cooling liquid for amateur radio vacuum tube power amplifiers. This cooling system is designed for adequate vacuum tube cooling, reasonable cost, and very low maintenance. By K8CU

Make and automatic antenna tuner based on Arduino and using economic card. This ATU Project can be installed outdoors and controlled remotely by an rs485 link

A lot of good things, not for QRP fans.