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Click on the center of a signal stream to decode the communication
Signal stream should show some serious red for enough signal strength to function
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Amateur radio (ham) digital chat (PSK31) at 14.070Mhz
This receiver is located in Charlotte, NC USA.
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PSK31 is an amatuer radio digital communication method which uses Phase Shift Keying. It was developed and
introduced by Peter Martinez [G3PLX] in December of 1998. It allows two hams to chat via their computer keyboard.
The method conserves bandwidth as compared to voice methods and is inherently immune to moderate interference making
it well suited for those that cannot put up a large antenna or transmit with high power. It is very popular with ham
radio operators worldwide. It utilizes the sound card of an ordinary PC with the audio output of the transceiver going
to the line in of the PC and the speaker out of the PC going (thru an impedance matching circuit) to the tranceiver microphone
input. The PC decodes the received signal and displays the text. Operator keyed input is modulated and sent out
the sound card speaker out jack. The software is almost all free open source and available for Windows, Mac OSX, and linux.
The mode uses single sideband mode and can be received on any quality shortwave receiver capable of SSB operation. Below is a list of links with more technical descriptions.
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If your not already a licensed ham
Operating a ham radio requires an FCC granted license unlike CB radio (Citizens Band). There are several levels of license, each of which requires a technical examination
to obtain. The test is multiple choice and it really isn't hard. A lot of kids get ham radio licenses. There are paid online courses you can take, as well as some
unpaid or advertiser driven web sites. One of the best solutions is a series of books by the ARRL (Amatuer Radio Relay League). The ARRL is the top organization for ham
radio and represents the hobby's interests when dealing with the federal goverment.
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Equipment you will need
Your options for the equipment you will need are diverse. There are inexpensive kits of tranceivers designed specifically for PSK as well as more pricey top grade from the
likes of ICOM, Yaesu, and Kenwood, as well as smaller companies such as TenTec, Alinco, Elecraft, and others. Standard tranceivers will require an interface between
the radio and the computer. These can be home made or bought. Some of the suppliers of these are
West Mountain Radio's RigBlaster, MFJ Enterprises, and others. There are also many
websites that describe how to build your own interface circuit. Building your own has always been one of the fun aspects of ham radio.
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PSK Software
The software you will need is often free and sometimes open-source. Popular examples include MixW32 (Win),
DigiPan (Win), gMFSK for linux, and other less popular titles.
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