Can you copy 25 stations that are at noise level at 25 wpm at the same time? All in a 1.4khz spectrum?
Fantasy is your part of the wet noodle of an antenna .... Mike KC7NOA Using psk31 ... my computer can ... > Date: Sun, 16 Sep 2012 20:46:19 -0700 > From: [email protected] > To: [email protected] > Subject: Re: Topband: TB digital > > On 9/16/2012 7:16 PM, [email protected] wrote: > > Finally, you cant mean to tell me that the little bit of space being used > > by digital at the top of the CW window causes a hardship on anyone.. heck > > half of the time the SSB stations are even down there and no one growls > > about that.. and wait until a SSB contest you wont find an empty spot in > > the CW band.. so what is the beef with 5 KHz or less being used, sometimes > > for a sound card digital mode when much of the CW band is empty 75 percent > > of the time. > > Right. And for the record, JT65 uses ONLY 2 kHz between 1838.5 and > 1840.5, and it's not unusual for there to be 6-8 signals in that bandwidth. > > Another point -- most digital operators I know LISTEN to their receiver, > especially when running RTTY, JT65, FSK441, and ISCAT. If you're > listening, of course you're going to hear if another station is there -- > assuming your noise level isn't too high. AND, because you've got a > spectrum display in front of you tuned to that 2 kHz bandwidth, and so > does everyone else operating that mode in that space, any rig with hum, > buzz, or audio harmonics is going to stand out like a you know what in > the punchbowl. > > AND, if all these signals were as full of hum and buzz as you imagine, > the combined hum and buzz resulting from all those guys transmitting at > once with their VFOs all set to 1838 USB would be very close to zero > beat, and would more or less add by 3dB for every doubling of the number > of dirty signals. Reality is that it doesn't happen that way, because > digital operators are NOT mostly lids, they DO work on making their > signals as clean as they know how, and other digital operators will make > sure that they do because they don't want the QRM. > > And since which is 1835-1840 "reserved for weak signal work?" I've been > on Topband for a while, but this is news to me. There used to be a "DX > window between 1830 and 1835, but that's long gone. > > But all of this begs the obvious question -- if I'm here in California > having fun on my run frequency in a contest (CW, of course) and 2,500 > miles away in GA Tom want's to work an S1 station who just got spotted > on my frequency, which I've busted my butt to find and hold..You think I > should QSY? Heck no. Now tell me how that is different from some guys > mostly running 10-20 watts, mostly into a wet string, using about 200 Hz > in a 2 kHz chunk of spectrum? > > 73, Jim K9YC > > > _______________________________________________ > UR RST IS ... ... ..9 QSB QSB - hw? BK _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
