On Fri, 12 Dec 2008 20:00:47 -0800, you wrote: In line below:
>I have been realizing over time that my QTH/antenna is high noise even >though I have underground utilities. I have been one of the complainers >about the startup blast of noise when the rig is first turned on. I now know >that my normal S-7 band noise is the underlying problem and when the K3 >turns on I get a +30dB blast of noise that is just shocking. That blast will >go away soon in a new firmware release. But the problem of high noise >remains. > > > >So what to do? I hate narrow bandwidth filters because they sound like a >hurricane whistling in a cave. Anything less than 1 KHz sounds terrible to >my ears. I think many of you cannot understand this but until now I thought >the K3 had terrible audio. I have been seeing many of you operate with 200 >Hz or so filters and I just shudder at the thought. The narrower the filter >the worse the audio. If you put a noise generator into your K3 and listened >to the hollow sound with narrow filters you might begin to understand my >problem. What happens when you use the DSP to narrow the passband on CW? Do you still get the sound you described? If you don't, you won't with the narrow filters either. From what you describe it sounds like you've had a bad experience with "ringing" narrow filters. I have the 400Hz and 250 Hz filters and they don't ring. Many other mfr's rigs have narrow filters that ring. My K3 does not, even when the DSP is set to 50Hz on CW. If you have a friend with a K3 and narrow filters, listen to his K3 and see if you hear what you are thinking you will hear with narrow filters. > > > >I use an inverted V on 40M, center up 35 feet. Okay this is a cloud burner >and maybe this is my real problem. I do see seasonable and daily variations >in background noise so my background noise is not 100% local. I have seen S3 >on 40M on occasion, usually early morning or night as we head into winter. >My S-Meter has been calibrated. Background noise is not just caused by electric lines on poles. You are fortunate to have buried power lines. I am not that lucky, but on the other hand I very rarely have that sort of noise here in the residential neighborhood I live in. Your neighbors may have all kinds of devices causing the noise you hear, or it may be just plain ole' atmospheric noise, but I doubt it. Electrical interference can be radiated for a long way. I once complained to my electrical provider about high noise. They found the noisy insulator 2 miles away. > > > >I know that people use separate antennas on the low bands because of noise. >Is there a suggestion for a really low noise antenna on 40M? I need a >drastic reduction or I need to move. My audio is quite fatiguing and it has >been quite a problem to operate CW if I need narrow filters to discriminate. >When I can copy at 1 KHz or broader, life is good. I operate on phone when >the SNR is good, if not I just don't operate. There have been a couple of interesting discussions here on the reflector about low noise RECEIVE antennas lately. Some of which have been laid right on the ground. If you have the Sub RX for the K3 or the KXV3 accessory you can TX on one antenna and RX on another. If you have either of these accessories try just laying 100 feet or so of insulated wire on the ground and see if that helps. The antenna on the ground will not have high S-Meter readings like the inverted vee, but you may find that signals you weren't hearing before are now there. Personally, I don't care much about the strength of the RX signals if I'm copying them better on my 280 foot loop that is about an average of 15 feet above ground on poles around the back yard. You might try a 40m full loop, but I'd try the wire on the ground first. > > > >Mike Scott > >AE6WA Tarzana, CA > >K3/100 SN508 > > Tom Hinson Childers, N5GE K3/100 #806, XV144, XV432 Mini-Modules http://www.eQSL.cc/Member.cfm?N5GE http://www.n5ge.com http://www.swotrc.net _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
