Hi Dave, Did anyone respond to you about this? (If I wasn't so busy right now, I would.) But I believe that the answers may be in the searchable archives.
http://lists.contesting.com/archives//html/Topband/ http://lists.contesting.com/pipermail/topband/ http://lists.contesting.com/mailman/listinfo/topband 73, Mike www.w0btu.com On Mon, Dec 7, 2015 at 2:30 PM, Dave Olean <k1...@metrocast.net> wrote: > I am somewhat new to 160 meters. I converted an old VHF tower at my house > to a 160 M 1/4 wave radiator in late 2013 and have been active since then > on a casual basis. Recently I started showing symptoms of the 160 Disease, > and have been looking for ways to improve things. The XYL has nixed > anything big (no more towers) so I am stuck with a single radiator, but I > can still work on the receiving side. I just built up an Africa beverage > (100 degree az) and was happy with the noise level on that antenna. It > seems extremely low and about as good as my Europe beverage. Recently, I > tried measuring each beverage and the vertical antenna to nail down the > noise floor using my K3 and P3 panadaptor. I wonder if these numbers are > good and how they compare with other setups. For the record, I set the P3 > at the narrowest span, 2 kHz. I used the preamp ON for the beverages and > the preamp off for the vertical. I recorded these levels on late Saturday > evening during the ARRL 160 contest, and then again, the following Monday > during the day. I recorded the following numbers... > > ANTENNA NOISE LVL DAYTIME > JA 330 deg -133 -138 > West 270 deg -125 -130 > SW 220 deg -125 -132 > Africa 100 deg -136 -144 > Europe 45 deg -138 -142 > Vertical Antenna -115 -123 > > All measurements were taken with the P3 panadaptor set at 2 kHz span. That > is important. K3 preamp is ON. These numbers taken at night are a moving > target. The noise can vary from hour to hour. I looked across the 2 kHz > span of the P3 and averaged what I saw. I seem to hear reasonably well with > the vertical, and in the past used it quite often. Now that I have a few > beverages, I hardly ever listen on the vertical anymore. Both the 220 and > 270 degree beverages suffer from power line noise and are 10 dB noisier > than the wires aimed East. I am thinking about maybe nulling out the power > line noise. I am sure that noise is killing my receive. > I guess I should make a real measurement of my noise floor at a > specified bandwidth of the receiver. That would require more work! I took > the easy way and set the P3 at minimum span and looked at the "grass > level". What numbers do others see on 160? > I live in a rural area in Maine near the NH border. I have a neighbor > across the street and another two about 1000 to 1200 ft away. I think my > location is pretty quiet, but I do often see interference that comes and > goes. I always hear two electric fences. One is a single snap every second > or so. The other is a pulsing burst of noise that lasts maybe 300 ms that > repeats every second or so. There is also a rather broad drifting signal to > my NE that is about 20 kHz wide and drifts around 1820 kHz. It is about 5 > dB above the normal noise. I suspect it is a mile away, but have not found > it yet. > > Dave K1WHS > _________________ Topband Reflector Archives - http://www.contesting.com/_topband