aki, ja1nlx, asked: Is there anyone who know articles or ideas about K2 FSK mod ?
------------------------------------ Most rigs today do not produce true FSK. That is, they don't shift the carrier frequency. Instead, they operate in Single Sideband mode and an external "frequency shift keyer" inputs changing audio tones into the mic connector. The RF output from the rig is then the suppressed carrier frequency + or - the audio tone, depending upon which sideband is in use. As long as the rig is set up properly with adequate sideband and carrier suppression, it's almost indistinguishable from true FSK. The tone generation is commonly done with a computer sound card, like many other digital modes today. Many hams have developed interfaces for use between their computers and their rigs. These interfaces are designed to provide the proper audio levels and to avoid ground loops that can cause hum or other problems in the system. Many have been published on the internet. Among them are S56AL's nice web pages at: http://lea.hamradio.si/~s57nan/ham_radio/ which features schematics of some interface units at: http://lea.hamradio.si/~s57nan/ham_radio/sb_intf/sb_intf.html These aren't specifically designed for use with the K2, but the basic principle is directly applicable to a K2 equipped with the KSB2 SSB board. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com