Thanks Guy for the well thought out response. Now we are getting somewhere.
The setup is a K3 using an Elecraft hand microphone feeding an Expert 1K FA solid state linear to a Windom antenna. The detector is a WaveNode WM2. The RF sensor module is between the Expert and the Antenna. The WaveNode is described on their web site (You can Google it,) and the manual is there too. The K3 is set up using ESSB with a width of 3.2. The tx equalizer is flat except for bands 7 and 8 which are set for -6db. The audio was my spoken voice so would be different from A to B. I have been told that I have a "radio voice" and should have been in broadcasting. I made a few radio and tv commercials for a company I worked for in the mid 1970s and to this day I have people come up to me and ask if I was on the radio in Cleveland. Somehow they remember the voice after decades. As you say, it is very base dominated. The WaveNode is a really fun toy which I am just now figuring out how to use. What I look for to see splatter is the presence of colors other than green in the Modulation Quickview window. If I see that, I know there is splatter. If I don't, then I assume I am OK. As you suggest, I will try this with the tx equalizer set up for narrow contest operation. I'll let you know what happens. In any case, I am convinced that the K3 should be operated with the Expert with each band of the K3 set for only the power necessary to drive the Expert to its rated power. In my case, this is 15 watts plus or minus a few. It is interesting to note that I can drive the Expert to nearly full power with my QRP K2. I'll report back on further tests. Thanks for all your good words. 73 de W6BK On May 15, 2010, at 6:06 PM, Guy Olinger K2AV wrote: > Hi Dave, > > Thank you for the pictures. Worth thousand words, etc. And there IS > difference between the two. Can you detail the setup from end to end, > particularly your RX setup and K3 TX voice settings? > > I'm not sure what your audio waveform is from exactly in A and B, > you'll need to tell us. But if that's human voice, it's a very > base-dominated voice spectrum, unlikely to generate obvious splatter. > The 0-400 or 0-500 band, whatever it is, is 18 db above the next > strongest band in your "modulation quickview", and so the lowest band > is completely controlling the power, not the attack of the silibants. > This would not be the measured waveform for a contest optimized voice, > with the treble accentuated for "punch", where splatter-producing > TX/amp setups show their true colors. > > Set up for contest "punch". Do the comparison with the lower > frequencies severely reduced in the K3 TX equalization, and the > compression up around 20-30. Or get your wife to do the voice and > have her holler at the mike like it was the kids (only a few > assumptions there...). Turn OFF the averaging in the program and > leave the peak hold on. The duration and hence the average power of > silibants are quite less than the lower frequencies, and the > distortion products off silibants even less. It is the distortion's > instantaneous peak power that causes the most problem, not its peak > power times duration (average power). > > The speech used for the test should be on a recording. Run the K3 > barefoot off the recording, bypassing the amp, measure and make your > pictures, and then include the amp and repeat from the recording > without changing anything on the K3. This is probably a 25 watt A/B > and a 100 watt A/B. The receiving device should be run with FIXED > gain, NO RX AGC, any overdrive issues worked out in advance. Compare > those spectrums. But even this is still approximate, because the RX > device (unless it's a very good RX device like another K3 or K2) can > create the highest distortion which covers up any true differences. > > The real test would be to run a very stable square rise and fall CW > dit with a pulse width of about 2 or 3 milliseconds with a repetition > rate of about one second, and repeating the test for longer pulse > widths. This requires a signal generator followed by a high power lab > linear amp instead of a K3 to drive the amp, but would isolate added > spectrum that occurs on predictable frequencies at predictable times > and can be precisely measured. The receiving device and presentation > would have to be certified for the general circumstances. I don't own > this stuff either, just get to drool on it during isolated > opportunities. > > As to others listening for splatter, one WOULD think others could hear > it. However, back in the day of controversy over what rigs had and > didn't have key clicks, it was amazing how many people could NOT hear > or otherwise detect the bad clicks on a MEASURED dirty rig, for > whatever reason I really don't know. So I'm skeptical since I don't > see much difference in hearing splatter and hearing key clicks. > > The problem I have, even if the SBE does manage to do amplification > relatively cleanly, is if someone else reads this thread later on > without any blowback on the claim, the readers extrapolate to other > amps and there it goes... So the SBE method is not going without > blowback. SBE may think they have created a marketing > differentiation, but for the time being they've crossed themselves off > my list on account of recommending smashmouth drive and ALC. What > else that I don't know about, yet? > > 73, Guy. > > On Sat, May 15, 2010 at 6:32 PM, David M. Elliott > <immondi...@earthlink.net> wrote: >> >> >> These two screen shots were taken using a WaveNode WN2. The exciter was a >> K3 and the amplifier was the Expert 1K FA. Both were SSB at 3.952 MHz. The >> conditions for both of these screen shots were the same except that the >> first one was using an exciter power of 25 watts and the second was using an >> exciter power of 100 watts. The amp was using ALC control in both cases. >> >> I don't see any signs of splatter in either case, do you? >> >> This test seems to support what the Expert folks are saying. >> >> 73 de W6BK >> >> >> On May 15, 2010, at 1:48 PM, Guy Olinger K2AV wrote: >> >>> Because if you are using something you can measure, like two tone, the >>> gains are already set and steady. To measure leading edge distortions >>> before an AGC loop or loops bite and settle takes some pretty >>> expensive lab equipment, both before and after the transmitter/amp. >>> What you got? >>> >>> It IS terrible advice. >>> >>> 73, Guy. >>> >>> On Sat, May 15, 2010 at 4:25 PM, David M. Elliott >>> <immondi...@earthlink.net> wrote: >>>> If increased distortion is guaranteed, why doesn't it show on the spectrum >>>> scope? >>>> >>>> We are obviously missing something here. >>>> >>>> 73 de W6BK >>>> >>>> >>>> On May 15, 2010, at 11:03 AM, Vic K2VCO wrote: >>>> >>>>> Sorry, with all due respect this is HORRIBLE advice. >>>>> >>>>> I won't argue with those that say that the ALC should be connected for >>>>> its protective >>>>> value. But it should not be depended on to control output level -- the >>>>> exciter should be >>>>> adjusted to produce approximately the drive required for full output. >>>>> >>>>> The SPE Expert may have an exclusive design, but it is not exclusive >>>>> enough to include a >>>>> time machine so that it can know how loud the operator is planning to >>>>> talk, and it doesn't >>>>> control the delay inherent in the exciter's ALC circuitry. >>>>> >>>>> The result is guaranteed to be increased distortion. >>>>> >>>>> On 5/15/2010 4:25 AM, Björn Mohr wrote: >>>>>> 2010/4/22, LA8AW<odd...@gmail.com>: >>>>>> >>>>>> >>>>>> Here is the statement from the developer of the SPE Expert 1K-FA - >>>>>> regarding >>>>>>> ALC, quoted from an early Expert Reflector:.... >>>>>>> >>>>>>> I hope this will clarify the SPE Expert vs K3 - and ALC !! >>>>>>> >>>>>>> We really suggest to always leave the transceiver's output power manual >>>>>>> control to >>>>>>> its maximum level because the EXPERT, thanks to its exclusive design, >>>>>>> will provide to >>>>>>> control that level as long as the required optimal value will be >>>>>>> reached. >>>>> >>>>> >>>>> -- >>>>> Vic, K2VCO >>>>> Fresno CA >>>>> http://www.qsl.net/k2vco/ >>>>> ______________________________________________________________ >>>>> 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 >>>> >>>> ______________________________________________________________ >>>> 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 >>>> >> >> ______________________________________________________________ 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
