This is the case where you want to analyse a recording by point-and-click to the ALE footprints on a spectrogram, made by SDRC’s File Analyzer. One decoder only: “Point and click” on a new level I will concentrate on how to use it for efficient monitoring. so this doesn’t need too much echoing it – RTFM. Paradigm Shift changes Monitoring StrategiesĬhris has written his manual with also the practitioner in mind, plus giving some backgrounds of how his software works. Chris already has developed a couple of unique (decoding) software, first for MacOS, then opened many of them also for Windows. The Black Cat ALE decoderhas been developed by Chris Smolinski, W3HFU, the smart brain behind Black Cat Systems. 10+ parallel channels, we now embrace with the Black Cat ALE decoder the very first multi-channel ALE decoder doing all this as one-stop shop. Demodulators and decoders are connected via Virtual Audio Cable, a software.Īfter having worked with one decoder, multi-instances, what proofed cumbersome when it came to e.g. Kuhn) is done with a wide-band SDR, free SDRC software featuring up to 24 demodulators, and a multi-channel decoder, accepting up to 24 different input signals to digest them. This nothing other like a paradigm shift (Thomas S. Now, state-of-the art covers up to 24 channels in parallel. The second generation mimicked a network’s receiver, scanning through all the network’s channels. The first generation of monitoring saw the DXer sticking to one channel for hours waiting for a signal. Now for the 3rd generation of ALE Decoders UDXF is a smart group which will help to unveil many of these secrets. However, DXer’s business is not always that easy, needing some detective work and even direction finding to nail cryptic callsigns like HQ3, AAA or 344013. Usually, you will receive the so-called sounding of the stations, like TWAS CHONKAPKA, reading “this was Cho’n-Chapka, Kyrgyz border control on the border to Kazakhstan”. Within the last three years, I have logged 10’000 different combinations of call signs and frequencies from Chile to Australia, from Alaska to South Africa. It is used from aircraft like AWACS, as from aircraft carriers, from mobile units to fixed stations. Since its introduction a generation ago, this concept is the tool of choice used worldwide by forces, diplomatic services, emergency agencies, police, militia, UN missions, drug enforcement, border control and even amateur radio. To establish communications, one just has to press the PTT key: the software looks for the best channel, switching to it, and you can speak or do some other type of communications. After a while, it builds up a table of channels with each of its reception quality. If the scanner identifies an ALE signal, it decodes it and saves some results like the quality of reception. The length of the transmission must be a bit longer than the number of channels, multiplied with the hold time of the scanner, at least ten seconds in the case of ten channels. Each receiver of the net is scanning through all channels, listening on each channel for about one second. It transmits a short message in a very robust, redundant mode (8-FSK) with forward-error correction. The headquarters then cycles through all the channels all 30 minutes, or so. This set of channels is programmed into the transceivers of all participants of a network. This information is used to develop a set of, say, ten channels of which at least one or, better, two will provide communications under all given circumstances. It starts with planning a network, defining the locations (regional, continental, worldwide) and the main times of traffic (daylight, dusk, night). With ALE, the knowledge of an expert simply slipped into software. HF Communications via ALE: Just press the (PTT) button With the advent of ALE, this number jumped to about 90%, re-vitalizing HF as a reliable tool of communications. Only 30% of first attempts to establish communications were successful. In the days before the MIL-STD-188-141-standard HF communications needed some knowledge about propagation and interference. Since its development in the late 1980s’, Automatic Link Establishment, or ALE, has made HF communications as easy as just pressing the PTT key of a transceiver. Here shown with 13 decoders only, Black Cat ALE decoder will read up to 24 different channels in parallel.
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