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#1
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Everytime I turn on my Pentium-4 PC, my shortwave signal gets completely
buried behind the noise. Beside shutting off the computer, what can I do to eliminate this noise? Thanks |
#2
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Try changing your monitor resolution, for example to 1024x768.
Move your radios away from the computer and monitor. "diddo" wrote in message ... Everytime I turn on my Pentium-4 PC, my shortwave signal gets completely buried behind the noise. Beside shutting off the computer, what can I do to eliminate this noise? Thanks |
#3
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Go over to your nieghbors house to do your listening. Make sure that he
turns off his computer. "diddo" wrote in message ... Everytime I turn on my Pentium-4 PC, my shortwave signal gets completely buried behind the noise. Beside shutting off the computer, what can I do to eliminate this noise? Thanks |
#4
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Try turning off and *unplugging* your monitor from the AC power, while the
comouter is left on. If this cuts down drastically on the noise, take a portable radio to your favorite comouter store and test some flat panel displays. Many of these are much less prone to interfering with radios than CRT based monitors. Rick Kunath |
#5
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Jack wrote:
On Wed, 14 Jan 2004 00:48:03 -0700, "diddo" wrote: Everytime I turn on my Pentium-4 PC, my shortwave signal gets completely buried behind the noise. Beside shutting off the computer, what can I do to eliminate this noise? Thanks Shut of the radio. g Seriously, move your antenna outside, or as far from the computer as possible and feed it using coaxial cable. It's hard to use a portable radio with a whip antenna in the same room as a computer or television. It will pick up a lot of noise. Here's what I did to eliminate the noise (URL-below). It requires building an antenna system outside with a good (RF) ground. http://www.anarc.org/naswa/badx/ante...e_antenna.html -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#6
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Changing your monitor resolution and/or refresh rate (if that last
adjustment is available to you) is an excellent suggestion. Each setting generates a different set of interference frequencies, and one may be compatible with SW listening. -- Reply address munged. You can figure it out. |
#7
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On Wed, 14 Jan 2004 00:48:03 -0700, "diddo"
wrote: Everytime I turn on my Pentium-4 PC, my shortwave signal gets completely buried behind the noise. Beside shutting off the computer, what can I do to eliminate this noise? Thanks The usual culprit is the monitor. Most of the Big ones are class A,not Class B, and I have never seen a Class monitor that actually operated within the Class A FCC limits (and I've been out on a test range many times). The other possible source is the switching power supply, but most of them are very heavily shielded if the computer is class B. (All laptops are class B, and in theory anything designed for home use is class B). Everything else operates at clock frequencies far beyond the HF bands. CRT monitors however user a very high power saw tooth to drive the sweep, and you can think of it as a very messy 100Khz calibrator. Most are on the order of 100Khz, and the wave form is very rich in harmonics (do a fourier analysis on a saw tooth), and the output of the Horizontal osicillator is usually tens of watts, so even if the harmonics in the SW band are 50 db down, that is a lot of power next to a shortwae that is trying to receive nanowatts. So get yourself an LCD display. |
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