well 98.5 hertz is .0000985 MHz but I don't know any frequency band that transmits in that low of a range so I would imagine it has to be converted into some other function of sound waveforms
hertz doesn't break down into decibels and sound pressure is measured in decibels. http://www.answers.com/topic/decibel Although decibel is a relative scale, it is often expressed as though it were absolute, with an implied reference signal. For sound, using the distinguishing label dBA but often just as dB, the reference is usually the threshold of human audibility, taken as sound of an amplitude (pressure) of 20 μPa and a frequency of 1 kHz. If either low or high frequencies are attenuated, giving emphasis to mid-range frequencies and beyond, the labels dBB and dBC, respectively, are used. (Such selective attenuation provides measures corresponding better to human sensitivities, with comparable readings for sounds of different pitches sensed by the ear as equally loud.) In electric communication circuits, dBW is relative to a signal of power of 1 watt, dBm to a power of 1 mW (hence 0 dBm = -30 dBW). Can the attenutation be broken down of comparative to wireless power in some fashion? http://en.wikipedia.org/wiki/File:Attenuation.jpg electricity) The exponential decrease with distance in the amplitude of an electrical signal traveling along a very long uniform transmission line, due to conductor and dielectric losses. (physics) The reduction in level of a quantity, such as the intensity of a wave, over an interval of a variable, such as the distance from a source. http://www.answers.com/topic/attenuation Hey I am just a layperson trying to figure it out as I go along. But what I am finding is dBW amd dBm (watts and miliwatts) is a piece of the puzzle as it has to do with signals of gains and losses of satellite transmissions converting into MHz and GHz and also now terahertz Yes it would seem it is not relative to the electrical grid but what about a wireless grid as a main frequency in some manner??? Like I said I am just a layperson, but for this thing to be humming around the world, I am leaning towards the modern of the functions of the wireless advancements being a piece of the puzzle of a bow string vibrating/conduction and EMF has to be in this somewhere On Jun 15, 4:27 am, Frank <[email protected]> wrote: > I recorded the sound using a small laptop with its internal > microphone. > I then used Spectrum Lab to analyse the recorded file. > The frequency is a very stable 98.5Hz so unless I have made a mistake > here, it is not related to mains frequency. > I have been running Spectrum Lab for several days to see if it > switches off at any particular time but its been on solid for the last > 3 days. > > I really need to make a recording with less noise. I have a > measurement microphone for my loudspeaker measurements but its not > portable enough and needs "phantom" power. > > Frank > > On Jun 15, 6:12 am, dboots <[email protected]> wrote: > > > > > Hi Frank > > > some form of sound density pressure wave forms seem to be a running > > theme > > > What kind of microphone did you use? > > Does the software give any idea what band of the spectrum the > > frequency is in??? > > Does the software give any idea if it is a low frequency MHz of a > > characteristic??? > > > Interesting your description if you walk in the direction of the Hum > > it disappears > > > Dee > > No Calif > > > On Jun 14, 2:03 am, Frank <[email protected]> wrote: > > > > I am currently investigating my hum in the southwest of England. > > > I can confirm that this one is an acoustic pressure wave (sound) and > > > not something esoteric. > > > I have been able to detect it using a microphone and view it using a > > > PC with audio spectrum analyser software. > > > > Its characteristics are: > > > It is louder outside the house than inside. > > > It is louder at the front of the house. > > > My Wife can also hear it. > > > It is constant level but switches off abruptly as I have heard several > > > times. > > > > Hearing is not so good at direction at such frequencies but if I walk > > > in the the direction that the hum "seems" to be coming from, it > > > disappears. > > > The level is highest just outside the front of my house! > > > There is no industry within the immediate area so its source still > > > remains a mystery. > > > > Frank > > > > On May 5, 12:23 am, Jim <[email protected]> wrote: > > > > > Steve, > > > > I live in East Aurora,NY > > > > > Jim > > > > > On May 4, 9:30 am, Steve K <[email protected]> wrote: > > > > > > Sorry to hear you have had it so long. we started hearing it in > > > > > western CT around Sept 2009. Our proofing looks top be changes in > > > > > natural gas distribution operations in our case. The theory is this > > > > > is a national problem, having been occurring for years some places and > > > > > accelerating in the last 4 yers to other areas. Where do you hear teh > > > > > HUM- town and stte is good enough > > > > > > Steve > > > > > > On May 4, 8:11 am, Jim <[email protected]> wrote: > > > > > > > My name is Jim and I am 64 years old. I have been hearing a low > > > > > > humming for 20 years now. I can't say that it is annoying as I am > > > > > > quite used to it by now. The best way to describe it is: a > > > > > > soft,low,hum that sounds like a hot air forced furnace when it is > > > > > > running or a distant train going down the tracks. Oddly enough, > > > > > > when I > > > > > > really notice the hum is when it turns off. Being on so often, the > > > > > > quiet of not hearing the hum is unusual. I could never hear the hum > > > > > > go > > > > > > on but I sometimes hear it switch itself off during the night while > > > > > > laying in bed. My wife thinks I'm nuts.... > > > > > > > Jim- Hide quoted text - > > > > - Show quoted text -- Hide quoted text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "Hum Sufferers" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/hum-sufferers?hl=en.
