vox circuit

Guanella 4:1 balun - This article reviews the proposition that a 4:1 current balun in the style of Guanella can be constructed with both pairs of windings sharing a common magnetic circuit.

Wire Harness Assemblies - Printed Circuit Board, Custom Overmold Cable Assembly, Box Build, System Integration, Sheet Metal

IC-746PRO TX Problem - 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.

Kenwood TS-50 IF-10D interface - Circuit of the Kenwood IF-10D interface for the TS-50 transceiver.

FT-817 ND Modifications - DRM reception / SDR output (IF 12 kHz), Using the internal VOX for the data jack, Connection of the mini speaker microfone ICOM HM-46

AP Circuits - Printed circuit board fabrication

5Spice - Analog circuit simulation program for the typical circuit designer. Commercial version for windows

NL5 Circuit Simulator - Analog circuit simulator for Windows (not a SPICE). A great tool for students, amateurs, as well as for experienced engineers. Free Demo.

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

Enable Low Cost RF Power Amplifiers - A new paradigm for low cost, reliable RF amplifier ‘pallets’ has been enabled by new circuit design, manufacturing and thermal management techniques

Power Aamps RF voltages - 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.

Build a Remote Control Antenna Switch - Remote Control Antenna Switch made with two circuits board

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

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

Resonant Frequency Calculator - 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.

Frequency Counter project  ^updated - Circuit and construction instruction designed by Mani VU2ITI

KI5YN QLF Filter - A microprocessor based interface designed to go between a standard Morse code key and a radio transmitter. The circuit receives a signal from the key, processes it, and re-transmits it to the radio.

QRP AM(cw) Transmitter for 10 meters - 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.

Lightning Protection : Protecting each I/O line - KB22UT Article on how protecting ham radio station and in particular I/O Lines such as AC power, coax cable, control circuits, telephone line.

HV power supplies - WV0NNI 2,800 VDC @ 2 Amps Continuous Variac adjusts filament voltage. A voltage doubler circuit, well suited for smaller, compact linear amplifiers.

M3 Electronix Semiconductor Analyzer Kit - A workbench instrument capable of testing transistors, diodes, FETs, usefull constructing QRP circuitry.

QRP AM CW transmitter - A simple low-power broadcast-type circuit, using a crystal oscillator integrated circuit and an a collector modulated AM oscillator

NB6M 10 Homebrew Receiver and Keying - Schematic of a homebrew receiver and keying

Sound Card interface - Interface to insulate the radio circuits from the computer by VK2GWK

Using An Oscilloscope - It allows you to take a peek into a circuit to see what is happening has it happens, irrespective of the speed with which it is taking place