80M Vertical antenna with capacitance hatpop
- Simple wire antenna cheap to make, using readily available materials, Low angle radiation, with rejection of high angle signals Wide bandwidth, with resonance at the 80M DX window (3.790-3.800 MHz); and Maximum height is 40 feet
CW Buffer, Amplifier & Preamp Sequencer
- The AMPSEQUENCER board is an advanced microprocessor driven control board specifically designed to buffer CW key signals while switching the amplifier to transmission, it can also be used to provide proper TX delay timing for RTTY and Pre-Amplifier proper sequencing
- Advanced microprocessor driven control board specifically designed to buffer CW key signals while switching the amplifier to transmission, it can also be used to provide proper TX delay timing for RTTY.
- MicroSignals produces a line of RF and IF signal processing components that offer high performance at an exceptional value. To achieve this MicroSignals began with an engineering team that possessed an excellent background in RF Transformer and Balun design.
- The SoftRock-40 is a small, low-cost, good-performing "software defined radio" receiver that plugs into a computer USB port and delivers I-Q audio signals to the computer's sound card. It was designed by Tony Parks, KB9YIG and Bill Tracey, KD5TFD as an "SDR sampler project" for hams everywhere to easily try out software defined radio.
USCG Navigation Center DGPS
- Differential Global Positioning Service (DGPS) is a land-based augmentation system that receives and processes signals from orbiting GPS satellites, calculates corrections from known positions and broadcasts these corrections via a Medium Frequency (MF) Transmitter to DGPS users in the Broadcast Site’s coverage area.
- JT65 is a digital protocol intended for Amateur Radio communication with extremely weak signals. It was designed to optimize Earth-Moon-Earth (EME) contacts on the VHF bands, and conforms efficiently to the established standards and procedures for such QSOs.
Unusual HF Propagation Phenomena
- This page has a collection of audio samples from unusual HF propagation phenomena, from round-the-world propagation to moonbounced signals , and to ducted transmission.
Short Wave Espionage
- Here you can access the book "Secret Signals, The Euronumbers Mystery" which was written in 1991 and is now out of print. Lot's of information on spionage and numbers stations
Covert Comms Archive
- Covert Comms was a monthly column wrote for the ACE newsletter from 1997 to 2002. The column was devoted to numbers stations, unidentified signals, intelligence information, and other related information
- Jason is a weaksignal communication program, especially tailored for LF work.
- SignalGen is a free (GPL) Linux (Xwindows GUI-based) utility that generates relatively low frequency signals with the use of a PC sound card. It is an entirely suitable replacement for a hardware signal generator if one doesn't require signals of a frequency higher than about 50 KHz. SignalGen creates any frequency between a fraction of one Hertz and an upper limit determined by your sound card's capabilities.
- TCUBE is a combination of a Spectrum Analyzer and a Two Tone Generator, with optional quadrature outputs. It can be used for measuring the intermodulation behavior of an audio circuit, and as a general purpose tool
- A freeware program to dig out weak signals buried in noise, functionally similar to the excellent FFTDSP of AF9Y, but with the added bonus of real time audio filtering of the incoming signals. Just point and click with the mouse, and the selected signal will stand out from the QRM and noise.
Filters and Ferrites in EMC
- This article is about the characteristics and use of various filters and ferrites for solving amateur radio electromagnetic compatibility problems involving breakthrough of amateur signals into domestic equipment such as television sets, video recorders stereo sytems etc.
Antenna Noise and Signal Cancelling at LF
- By using the signals from two antennas, controlling their relative amplitudes and controlling the phase of one of them, unwanted signal or unwanted noise can be phased out. Circuitry is described which uses the signal from a wire antenna to provide selective cancelling against the signal output from an LF loop antenna.