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#1
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"mystery" static in my area.... S-9 worth of noise!
What do you (not) know about this noise? |
#2
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"0ff_Ramp" wrote in message ...
"mystery" static in my area.... S-9 worth of noise! What do you (not) know about this noise? Not sure where its coming from. It ususally starts late morning and lasts up to midnight, its very much on time every day. |
#3
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"mystery" static in my area.... S-9 worth of noise!
What do you (not) know about this noise? Not sure where its coming from. It ususally starts late morning and lasts up to midnight, its very much on time every day. With the timeframe you mention, seems like a business establishment - restaurant/bar? Any new electric signs in the neighborhood? Can you isolate the noise to any degree??? I'll assume you have already eliminated your own residence by shutting off all the power? I recall one day certain cable TV channels were being obliterated. Then at night I turned on the AM radio and intermittent noise was 20 over. From the noise pattern and time of use I had speculated that the noise was caused by an electric blanket thermostat. This went on for days before I couldn't take it anymore. I used a small portable receiver and isolated the noise to my neighbors home. They had recently had a newborn baby. Turns out they had started using a baby wipes warmer (cheap, made in China, junk, fire hazard.). As soon at it was plugged in for the evening diaper routines all hell broke loose. |
#4
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gil wrote:
"0ff_Ramp" wrote in message ... "mystery" static in my area.... S-9 worth of noise! What do you (not) know about this noise? Not sure where its coming from. It ususally starts late morning and lasts up to midnight, its very much on time every day. Before you get into noise cancellers, go for a walk around the neighborhood with a portable radio to locate the noise source. Maybe you can eliminate it so you won't need the canceller. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
#5
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It wouldn't necessarily surprise me if your source of
noise is the same as mine: a television set. In my case, it's our main television set, an 8 year old 25" RCA that I pick up noise from with my outside antenna whenever it's turned on. --Mike L. "starman" wrote in message ... gil wrote: "0ff_Ramp" wrote in message ... "mystery" static in my area.... S-9 worth of noise! What do you (not) know about this noise? Not sure where its coming from. It ususally starts late morning and lasts up to midnight, its very much on time every day. Before you get into noise cancellers, go for a walk around the neighborhood with a portable radio to locate the noise source. Maybe you can eliminate it so you won't need the canceller. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
#6
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![]() Michael Lawson schrieb: It wouldn't necessarily surprise me if your source of noise is the same as mine: a television set. In my case, it's our main television set, an 8 year old 25" RCA that I pick up noise from with my outside antenna whenever it's turned on. The worst noise source I had was a VCR. It was producing noise all over the shortwave bands even in standby mode. It took me a while to find it out..... |
#7
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Luckily our VCR or our other audio/video equipment
don't radiate anything, but then again, it's bad enough with just the television. In our case, the best thing to do is to turn it off. If the guy's got a neighbor that simply lives with the televison on most of the day, he might be out of luck with a regular antenna. --Mike L. "Volker Tonn" wrote in message ... Michael Lawson schrieb: It wouldn't necessarily surprise me if your source of noise is the same as mine: a television set. In my case, it's our main television set, an 8 year old 25" RCA that I pick up noise from with my outside antenna whenever it's turned on. The worst noise source I had was a VCR. It was producing noise all over the shortwave bands even in standby mode. It took me a while to find it out..... |
#8
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"0ff_Ramp" wrote in message ...
"mystery" static in my area.... S-9 worth of noise! What do you (not) know about this noise? This is a superb question, because the ability of the device to remove noise has alot to do with the nature of the noise. If the noise is local and well-defined, if it is coming into your system via the antenna (as opposed to the electrical lines) and especially if it is the *only* bad noise you have, then a noise canceller will probably take it out quite nicely. If the noise is distant (such as an offending HF station via skywave) and the other two criteria still apply, it will still work, but not quite as well. If any two of these criteria are not met, then it is unlikely that the unit will give satisfaction. For two different noise sources, two units in series might work, but I have never tried this. For this, it is probably preferable to have a radio that has noise-cancelling devices (Noise blanker, DSP, etc) plus a single external unit. Also, some units (the MFJ-1026 notably, which I use) comes with a built-in aux "noise" antenna. It works, a bit (especially on certain wavelengths such as 25m and 60m - 90m, where it works quite well) - but for serious noise, it is best to have a dedicated external antenna that comes reasonably close in character to your main antenna. This, because you want both antennas to be "hearing" the same noise. Two roughly parallel 40-foot (12m) or longer random wires about 20-50 feet (6m to 16m) apart would be nearly ideal; but I use a DX-Ultra (essentially a center-fed dipole assembly) with a random wire of about 60 feet as the aux antenna, and it works pretty well for most noise. The way the units are configured, you can phase one, the other or both antennas together for the best noise reduction. On the MFJ units, the aux antenna has both a gain control and a preamp, which is nice, but it would be even better if these features were switchable from aux to main sometimes (a fairly simple modification inside the unit can achieve this, if you aren't afraid to do minor surgery). With my unit in stock condition and with the internal jumpers configured per the instructions, I can reduce most constant modest static 3 to 5 S-units; strong static or impulse noise from S-9 down to below the noise floor at S-1 or less (a good noise blanker will accomplish about as much); offending groundwave stations (on SW or MW) a comparable amount; and offending skywave stations about 3 S-Units (typically). These correspond to dB reductions of about 18 up to 50 dB or more, depending on the noise. When I have an obnoxious noise that cannot be remedied by the noise blanker, notch or DSP, I tune off the desired station frequency to a quiet spot nearby 5 or 10 kHz away), adjust the noise levels and phase according to the directions until the noise is reduced maximally, then tune back to the station. You don't want to tune very far away to adjust the device, because the settings are frequency-dependent. Done properly, this works very well. The unit advertises that it can take out static crashes from lightning and other intermittent noise sources, and it may be true, but the nature of these noises makes it very difficult to adjust the device with any precision. I like mine alot - for the city/suburb dweller or the random person with horrid noise, it works minor miracles. Bruce Jensen |
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