Re: Topband: Restoring the Signal to Noise Ratio
I'll put my tongue in the other cheek and ask how me increasing my TX power improves the SNR on a received DX signal? Wes N7WS On 3/14/2020 4:20 AM, Rob Atkinson wrote: This is only half tongue-in-cheek. With the ambient noise going up, and there being limits to the size and cost of receiving arrays most amateurs can build, the next logical step is to raise the output power. Perhaps the FCC should be >petitioned to raise the legal limit? They were supposed to safeguard our frequencies against interference (man-made noise included), but since they have failed to do that, they should allow more >power to restore the original signal to noise ratio? (Which some already do, anyway.) It's a legitimate idea and probably one of the best ways of dealing with the problem when you think about what can and can't be controlled. I've been seriously suggesting the power limit be raised or eliminated for a few years now. Eliminating the power limit isn't as horrible as it sounds at first, because there are a lot of other factors that would prevent a ham from running crazy high power, but I don't want to digress off into that here. Unfortunately just raising the power limit is probably never going to happen. U.S. hams already have it pretty good compared to some other countries, and the RF exposure hysteria, which disregards the fact that about 99.9% of ham operations are harmless, would prevent it. Also, the power socialists who think everyone should be limited to 100 watts would jam FCC with objections. By the way, the power limit debate goes back to the 1930s; it isn't new, but the noise floor problem is relatively new. You can only do so much with rx antennas, phasing, DSP (which always adds distortion from my experience), filters and tx antennas. Of all the ham band allocations, medium wave is probably most in need of power. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Restoring the Signal to Noise Ratio
>This is only half tongue-in-cheek. >With the ambient noise going up, and there being limits to the size and cost >of receiving arrays most amateurs can build, the next logical step is to raise >the output power. Perhaps the FCC should be >petitioned to raise the legal >limit? They were supposed to safeguard our frequencies against interference >(man-made noise included), but since they have failed to do that, they should >allow more >power to restore the original signal to noise ratio? (Which some >already do, anyway.) It's a legitimate idea and probably one of the best ways of dealing with the problem when you think about what can and can't be controlled. I've been seriously suggesting the power limit be raised or eliminated for a few years now. Eliminating the power limit isn't as horrible as it sounds at first, because there are a lot of other factors that would prevent a ham from running crazy high power, but I don't want to digress off into that here. Unfortunately just raising the power limit is probably never going to happen. U.S. hams already have it pretty good compared to some other countries, and the RF exposure hysteria, which disregards the fact that about 99.9% of ham operations are harmless, would prevent it. Also, the power socialists who think everyone should be limited to 100 watts would jam FCC with objections. By the way, the power limit debate goes back to the 1930s; it isn't new, but the noise floor problem is relatively new. You can only do so much with rx antennas, phasing, DSP (which always adds distortion from my experience), filters and tx antennas. Of all the ham band allocations, medium wave is probably most in need of power. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Restoring the Signal to Noise Ratio
This is only half tongue-in-cheek. With the ambient noise going up, and there being limits to the size and cost of receiving arrays most amateurs can build, the next logical step is to raise the output power. Perhaps the FCC should be petitioned to raise the legal limit? They were supposed to safeguard our frequencies against interference (man-made noise included), but since they have failed to do that, they should allow more power to restore the original signal to noise ratio? (Which some already do, anyway.) ;-) 73, George, AA7JV On Fri, 13 Mar 2020 05:40:30 -1000 Dave Cuthbert wrote: The document was published last year so we might assume the noise graph is up to date. To put this in perspective, To put the ITU-R P.372-14 claimed noise in perspective here's the calculated antenna terminal voltage for a 100% efficient 1/4 wavelength vertical in 500 Hz bandwidth. S-units are also shown. Quiet receiving site -- 4.7 nV/m, vert 1.3 uV, S-4 Median city noise -- 66 nV/m, vert 19 uV, S-8 Dave KH6AQ (formerly WX7G) _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
