Dear Dr. Imre Bartfai, "dr. Imre Bartfai" on 2001-04-24 05:28:41 AM > I badly need an english term for the following > (in German: Tonfrequenz-Rundsteuerung, Rundsteuerung is a "control circuit". A direct translation of "Tonfrequenz-Rundsteuerung" gives me "audio frequency control circuit" (the signal is modulated to somewhere in the 20 Hz to 20 KHz band). That would allow common cheap modems to be used. If the frequency is higher than 20 KHz, maybe you have a "FM control circuit" (frequency modulated). -- David Cary -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.