Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!sdd.hp.com!elroy.jpl.nasa.gov!decwrl!mcnc!borg!oscar!tell From: tell@oscar.cs.unc.edu (Stephen Tell) Newsgroups: sci.electronics Subject: IF frequencies (was Re: Audio Jamming) Message-ID: <1687@borg.cs.unc.edu> Date: 19 Feb 91 02:53:41 GMT References: <8071@exodus.Eng.Sun.COM> Sender: news@cs.unc.edu Organization: University of North Carolina, Chapel Hill Lines: 17 > Broadcast band FM receivers ordinarily use an >IF of 10.7 MHz, TV receivers use a picture IF of 45.75 MHz and a >sound IF which is 4.5 MHz below that, at 41.25 MHz. TV receivers built >before 1950 or so use a picture IF of 25.75 MHz. Broadcast AM receivers >use 455 kHz as the IF freq. Just out of curiosity, what services are licensed in the bands where all these common IF frequencies fall and thereby get all the interference from cheaply-designed consumer junk? I suppose emmissions of these frequencies are regulated just like noise from computer gear; are the limits the same? -------------------------------------------------------------------- Steve Tell tell@cs.unc.edu H: +1 919 968 1792 #5L Estes Park apts CS Grad Student, UNC Chapel Hill. W: +1 919 962 1845 Carrboro NC 27510