Sounds like you are listening to your TV set. The strong 3.58 MHz signal you are hearing is the Color Burst oscillator frequency, and the 15.7 kHz spaced frequencies you are hearing are the harmonics of the horizontal sweep in the TV. They would have sidebands at 59.94 Hz, which is the vertical scan rate, and yes, they would be very stable as quite often the ultimate source of these frequencies is an atomic clock, or at least a high stability precision oscillator. Your TV phase locks to the synchronizing signals from the TV station with a high degree of precision. You should also be able to hear them all over the AM broadcast band. If the offending TV isn't in your house, then it might be a neighbor or two. A little direction-finding with an AM broadcast portable will help you pinpoint the offender. Getting them to buy a new TV, which may or may not be better shielded another matter.
Bob Bruner WB4TAJ/9 --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html The reason this message is shown is because the post was in HTML or had an attachment. Attachments are not allowed. To learn how to post in Plain-Text go to: http://www.expita.com/nomime.html ---
