^If it is high pitched then it can be attenuated by a good set of ear protection. Preferably a combination of expanding ear plugs and some wrap around headgear. If the sound does not attenuate, it is in her head. ( Physically or psychologically ) How far away from the antenna must she get to lose the audio ? AGSC^ On 2006-Sep 05, at 21:46hrs PM, Jinx wrote: A friend has been giving me grief for some few weeks about noise she says is coming from a microwave tower about 300m from her home and keeping her awake in the quiet of the night. She describes the sound as a constant high-pitched tone. I have every reason to believe she is not crazy, and she assures me she has not got tinnitus or any other hearing problems. She may be dwelling on the problem (though she says she isn't), which might tend to aggravate any auto-suggestion. I'm getting all this from a woman who is quite frazzled and cranky after many sleepless night but who hasn't lost the plot. She's still quite rational about possible causes, but not being technical at all she has a limited number of causes to think about. There aren't many houses around where this tower was put up so she hasn't neighbours to discuss it with She reckons she's being fobbed off or stonewalled by the owner of the tower (BCL) and the local council and as she doesn't seem to be getting anywhere on her own I've offered to try and gather evidence. Including, if I have to, trying to record the noise to present to someone as hard evidence. What she has so far are just opinion and supposition. I haven't heard the noise myself, she's quite some distance away and a visit hasn't been possible yet. She said a tech, ISTR, had suggested (I don't know the circumstances or context of the conversation) it was 15kHz, which made me think perhaps a switch-mode with something loose, but the tone she sung over the phone is nowhere near 15kHz. Probably more like 3/4 the way up a piano, definitely within almost everyone's hearing range, which you'd think would be easily heard by anyone. A late-shift engineer came to her home and thought he kind of heard something, but seems not in the "my god, how do you sleep with that racket ?" league or a problem would have been immediately apparent If the tower is in fact putting out this mysterious tone, I wonder about a couple of things (1) Apparently the sound is no louder at the tower. I would have thought it would be, given the sqrt law unless - (2) there is some beat frequency being created at her home by two or more inaudible frequencies, and she just happens to lucky enough to be at a place where a combination of beat frequency and distance make a node Any thoughts ? Any similar experiences ? -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AGSC Augustus Gustavius Salvatore Calabrese 4337 Raleigh Street Denver, CO 720 222 1309 303 908 7716 cell adding " spam2006 " bypasses my spam blocker. Please place in the text or at the END of the subject line. ( i am hard to reach by phone ) All ideas, text, drawings and audio , that are originated by me, and included with this signature text are to be deemed to be released to the public domain as of the date of this communication . AGSC ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist