Jim, Thank you for the extended explanation, it helps! I want to be sure I understand the rig, the Panadaptor, and how they interrelate. THank you again!
-- Thanks and 73's, For equipment, and software setups and reviews see: www.nk7z.net for MixW support see; http://groups.yahoo.com/neo/groups/mixw/info for Dopplergram information see: http://groups.yahoo.com/neo/groups/dopplergram/info for MM-SSTV see: http://groups.yahoo.com/neo/groups/MM-SSTV/info On Mon, 2014-04-28 at 09:27 -0700, Jim Brown wrote: > On 4/28/2014 8:37 AM, Vic Rosenthal K2VCO wrote: > > What should work is to use the spectrum display of the P3. If you want > > to know, for example, the bandwidth of a signal at 30 dB down, you > > just find the points where the 'skirts' of the signal are 30 dB below > > the peak. This is easy to do on the P3 which can display the signal > > strength in dBm. > > Yes. And as N1AL recommends, use peak hold. I've done spectrum plots of > various signals and conditions with the P3. I usually set the SCALE for > a pretty wide range (like 72 or the full dB), and set the SPAN to about > 10 kHz. I use both the Peak Hold Mode and the Average Mode. In both > modes, but especially with Peak Hold, we must take care to differentiate > sidebands from other stations. I try to set the reference level so that > the peak of the signal is at one of the level lines and the noise level > is near the bottom of the display. > > With almost any rig, you'll see small signals down the sides of the > slope that are intermod products, and they are usually symmetrical on a > CW or RTTY signal. A clean SSB signal should be well confined by the > bandpass filter limits of the audio and TX filter skirts. Anything that > extends beyond that is IMD. When a rig is badly overdriven, it's common > to see splatter as horizontal streaks extending above and below the > signal frequency. > > Last week, I was on 20M SSB trying to work a weak DX station, but what I > heard was massive splatter from a QSO about 5 kHz up the band. One guy > was relatively clean, but the other was not. I broke the QSO to tell him > he was clobbering a weak DX station. Turns out he was an aeronautical > mobile using whatever radio was onboard. He didn't know whether he was > transmitting AM or SSB, but thought it was AM. I assured him that it > was, indeed, USB, and that the problem was that he was likely > overdriving it badly. He went QRT to figure it out. > > As a percentage of transmitted signals, I don't find contesters any > better or worse than non-contesters -- we contesters stand out because > during a contest, there are a LOT more of us. :) I'm retired, so I have > access to the ham bands during the day (when I'm not working on > something else). It's not at all uncommon to tune around 30, 40, and 80 > during a weekday and hear fewer than a half dozen signals on these bands > (if you hear any at all), and no more than a few dozen on most of the > higher bands. Compare that to a major contest, when there are several > hundred workable signals on every band from any given location for the > duration of the contest, and for stations with better antennas, perhaps > 2-4X that number. The winners of contests like the ARRL SSB Sweepstakes > make more than 2,000 QSOs, and you can work a station only once. > > 73, Jim K9YC > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to d...@nk7z.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
