modulation sound files

Monster Quads - N6LF tells us about his monster two-element 40-meter quad, with bonus three elements on 20 and 15 meters.

Single support gain antennas for 80-160 meters - On 80 and 160 meters an antenna with modest gain and good front-to-back (F/B) ratio, along with a steerable pattern, can be very effective for contesting.

The Lazy-H vertical antenna - A versatile antenna for dx work

A Horizontal loop for 80 meter dx - This 80-meter quad loop system requires only supports of modest height—a better single-element antenna may be hard to find by VE2CV

Bruce arrays for 80 and 160m - Antennas with gain and bandwidth for 80 and 160 meters band. Simple wire antenna capable of considerable gain

Indoor multiband dipole - This indoor dipole is available in two version for 20-10 meters and 40-10 meters. EZNEC data files available by HB9MTN

Conductors for HF Antennas - Putting up an antenna for the low bands? What kind of wire will you use? This analysis may change your plans.

Conductors for HF antennas : Foil - About foil conductors

The DBJ-1 VHF-UHF Dual Band J-Pole - Searching for an inexpensive, high performance dual band base antenna for VHF and UHF ? Build a simple antenna that uses a single feed line for less than $10.

Antentop: Loop Antennas - Article on radiation patterns of small loops, equivalent circuits of loop antenna, small loops as receiving antennas, ferrite loops

Optimizing half-wave sloper arrays for 160 meters - This article presents a 160-meter variation of this family of antennas and, more importantly, a discussion of the details of how to get such a beast working really well.

Another way to look at vertical antennas - What iss the difference between a dipole and a vertical? Maybe not as much as you think. Come along and try another point of view.

Verticals. Ground systems and some history - Article gives a good overview of the basics and reflects the accepted wisdom from BC antenna work.

Trapped antennas - ARRL index of document about trapped antennas and notes on traps usage

Short radials for ground-plane antennas - Think your elevated radials always have to be full size? N6LF lets you in on some great ideas to lessen the “wingspan” of radials, especially near the beach.

Digi Mode Sound Files - Mp3 and wav files linked from this page are intended to help your understanding of what the different digital modes sound like

TWPSK - A linux soundcard based PSK program by DL9RDZ and WA0EIR

TWCW - This linux program will send Morse Code via soundcard or serial port by WA0EIR

BIP Electronics Lab Oscilloscope - Freeware windows oscilloscope uses the sound card's input to measure signals. This means that the quality of the scope depends on the quality of your sound card. The scope automatically uses the highest sample frequency available at the input that you select

SweepGen - SweepGen turns a PC into an Audio Oscillator and Sweep Generator which can be used for testing audio or educational purposes. In conjunction with audio test instruments, you can make frequency response plots. SweepGen uses the sound card in your PC to produce sinewaves

AVR Beacon Keyer Project - Description of an HF beacon keyer with telemetry. What makes the keyer rather different is its versatility - it is a multi-mode unit, with ASK and FSK modulation, sending Feld-Hell and Morse on command.

Narrow Band-Pass filter for HF - Band-pass filters can be critical components in competitive stations. This setup may help put your station on the map.

Clean Up Your Signals with Band-Pass Filters - These inexpensive, easily built filters can be the buffer you need between the signals you want to hear and send and those you don’t!

Clean Up Your Signals with Band-Pass Filters part 2 - Part 2—You’re now much closer to saying goodbye to your unwanted signal problems!

Band-Pass Filters for HF Transceivers - Do your multiple-transmitter field day or contest efforts suffer from intrastation interference ?