Search results

FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusiast.

The 60 Watt linear amplifier is simple all solid state circuit using power mosfet IRF840.

Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

A simple circuit which will generate a 700 Hz tone into any FM transceiver allowing an amateur to practice CW with another amateur on a 2 meter simplex frequency.

Projects and design atv de ik1hgi Progetti, circuits, master, fotos in Italian

The IC-746PRO is a great rig. But it has a few reliability issues, especially with the earlier-production units. This article addresses four problem areas:. IC151 on the RF Unit. Driver circuit on the PA Unit. HRX-muting circuit on the CTRL Unit. Predriver on the PA Unit.

Versatile transmit interface circuit

CTCSS Decoder and Encoder, DTMF Decoder projects

Design Guidelines for Bipolar Transistor Audio Preamplifier Circuits By Mike Martell N1HFX

This web based application will compute circuit values required for an L-C circuit to resonate at given frequency. Also it will compute the resonant frequency if given values for L and C.

HAMIC, is a program designed to simplify a number of calculations commonly used by HAMs. It is designed for the HAM radio hobbyist, but may be useful to others as well. HAMIC has a simple to use, but powerful graphical interface that allows solving simple circuits such as resistors in series or parallel, or more complex circuits such as L networks or T networks. As well, other calculations such as SWR and reactance conversions are supported. Windows shareware.

Building a PEP Power circuit for all analogue watt-meter

Circuit diagrams drake tr7, Schaltbilder Drake Tr7, antenna tuners, baluns, and home brew power supplies, dual tone ssb test generator, zweiton ssb test generator, zweiton testgenerator, dual tone test generator by DK4DDS

Analog circuit simulator for Windows (not a SPICE). A great tool for students, amateurs, as well as for experienced engineers. Free Demo.

It is a application which can be used for troubleshooting CB radio faults, by giving a graphical display of the normal operating frequencies generated by various parts of the CB radios circuits, it can help you identify if a frequency is incorrect or even missing. Another good use for this software is simulating possible frequency expansions, as it allows you to choose any frequency that the PLL is capable of generating, so you can see what the radio will allow you to get !

A PC headset to Rig adapter. Include a circuit diagram and a full part list for the project

The circuit is based on two AD8307 log amplifiers, which are connected to the forward and reflected ports on a directional coupler

FAR Circuits is exclusively a manufacturer of Printed Circuit Boards for electronic projects that are used by the Amateur Radio and electronic hobby enthusias

Design guidelines for Op Amp audio preamplifier circuits by Mike Martell N1HFX

SimSmith is a highly interactive, real time Smith chart graphing program. Circuits are constructed using drag-n-drop. Load files can be imported from the EZNEC and CocoaNEC antenna simulation software and from the AIM4170 and miniVNApro antenna analyzers. Circuits and load files can be of any size. Key Features: SimSmith is one of the few Smith chart packages which models transmission line losses. SimSmith also allows the description of circuit elements using algebraic equations. SimSmith has only one screen and allows the screen to be resized to increase workspace or readability.

The circuit described below will substantially reduce or completely eliminate interference from almost any local source whilst leaving the wanted signal relatively unaffected, even though it may be on the same frequencey by TREVOR, G3ZYY

The document is a technical guide on designing RF filters for radio frequency applications. It covers topics such as interference suppression, band-pass filters, and low pass filters, with a focus on filter design and circuit filters.

Minimal interface circuits for receiver and transmitter audio, also for PSK31

AM-6154 222MHz grid Conversion Information by N0UK

Wikipedia page about regenerative circuits in designing receivers.

A circuit which had been used in many other application before. The configuration described here is optimized for IPHONE/radio operation.

The digital wattmeter project was created for the purpose of measuring power in the range of 300nw to 30w.

Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window. Run on Linux.

Simple circuit, with a simple push, transmit a memorized Cw messages

This circuit consists of microphone amplifier and a high pass filter. Suitable to improve signal readability.

A DIY project of a WiFi 10 elements Yagi antenna

A rotator modification by W4ZT

An easy to deploy antenna, commonly considered the best solution for portable operations. Thir article includes a simple LC parallel circuit to match the impedance by IW7EHC

Development of the Slim Jim antenna for HF

DigChip is a provider of integrated circuits documentation search engine, it's also distributor agent between buyers and distributors excess inventory stock.

Direction finding projects, useful tools for t-hunting operations

Ebook by Akira Matsuzawa Tokyo Institute of Technology, Building blocks in RF system and basic performances, Device characteristics in RF application , Low noise amplifier design, Mixer design and Oscillator design

This simple and cost effective interface circuit is designed for use with any ICOM amateur radio equipment with CIV interface

In this project, you will make a simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator.

PIC Programmer software package that allows you to program all types of serial programmable Integrated Circuits using Windows 95/98/NT/2000/ME/XP

Diplexer is a passive device, a special filter circuit that seperates 2 different bands, not to be confused with the duplexer that usually separate 2 different frequencies on the same band.

A simple simple sweep generator circuit design where the sawtooth is generated by the PNP transistor and a 555

This program intended for electronic circuit analysis (mainly for Linux). ViPEC is a powerful tool for the analysis of high frequency, linear electrical networks.

This Z-Match is a link coupled all-band tuner. Two all band tank circuits cover 3-14mhz and 14-30mhz. The tank output links are selected with a very heavy duty SPDT rotary switch.

By Prof. T. K. Mani - VU2ITI

Building the WB2HOL foxhunting beam antenna

The Remote Control Antenna Switch consists of two circuit boards. The control unit and the remotely controlled switch

A schematic for a DX circuit protection for the Yaesu FT-817, provides protection from the external power supply overvoltage by DL2LTO in german

This circuit stores a single morse code message as bits in an EPROM chip, the message is sent to a relay which can key a CW transmitter.

This document details the design and construction of the PA70H, a 50-watt RF amplifier for the 70MHz (4-meter) amateur radio band. Built around the Mitsubishi RD70HVF1 MOSFET transistor, the amplifier delivers 45-55W output with 3-5W input power while operating on 13.8V DC at approximately 7-8A. The PCB design incorporates multiple protection circuits including overcurrent, SWR, and temperature control. The amplifier features various control modes including GND PTT, +13.8V PTT, and RF VOX. Two versions are available: PA70HLI (requiring 100mW input with additional driver) and PA70H (for 3-5W input). The comprehensive documentation includes circuit diagrams, assembly instructions, and performance data showing successful operation from both 100mW and 3.5W input sources.