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b"What use is an F-call?\\n\\nRecently I spoke about digital voice communications. I made mention of the CODEC2 project being developed by Dave Rowe, VK5DGR. I also made reference of the kinds of things that digital voice improves, battery life, channel separation and bandwidth.\\n\\nOne of the things I didn't mention, mainly because I still had to learn what it meant, is that CODEC2 has an estimated 13dB gain over Analogue FM.\\n\\nTo explain what that actually means, you might recall that an S-point is 6dB, that means that if you use CODEC2, you gain more than two S-points, that's a little like turning up the transmitter power from 10 Watts to 200 Watts.\\n\\nIf you look at it another way, if you have a Yagi and you install the same Yagi next to it, and connect it up properly, you've doubled the power and gained 3dB. If you do that again, you have 4 antennas and 6dB, if you do it again, you have 8 antennas and 9dB, again, 16 antennas or 12dB gain.\\n\\nSo, the performance that we're talking about is something that you can either visualise as turning up the power from 10 Watts to 200 Watts, or using an antenna array with 16 antennas.\\n\\nSo what is this magic thing called CODEC2?\\n\\nWell, as I said previously, a CODEC is a piece of software that encodes and decodes stuff.\\n\\nAn example that you might be more familiar with is an MP3 file. You open your sound file, and save it as an MP3. The new file is much smaller but it retains most of the fidelity of the original when you play it back. The same is true for other things in use. Your mobile phone uses a GSM CODEC to make your voice travel across the airwaves as bits, rather than raw audio, like the old analogue phones we used to have.\\n\\nThe aim of all of this is to reduce data use, to increase availability of channels and to deal with error correction.\\n\\nCODEC2 does all that, for us, here, in Amateur Radio Land, and of course, it can also be used in the rest of the world, for example for mobile phone communications, making it possible to use less power to transmit the same signal and thus use less battery, making your phone last longer.\\n\\nI'm looking forward to a CODEC2 mode on my radio to go with the AM, FM and SSB modes already there.\\n\\nI'm Onno VK6FLAB"