Re: [Elecraft] [K3] Noisy K3 receiver
DM4iM wrote: > > Gentlemen, > i played with AGC THR on 2 different K3's this afternoon. > To me both sound more pleasant with AGC THR 2 on strong signals. > But digging out the weak ones becomes difficult, the signal sounds mushy. > Try it, change AGC THR while listening to a very weak ssb-signal. > It becomes more and more readable the closer you get to 5, the default. > The signal stands out, even though the noise is higher. > That fooled me the first time I tried it. The noise isn't higher, everything is louder. If you increase THR while at the same time reducing the AF gain to keep the signal level the same, the difference should be more noticeable. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4194195.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Gentlemen, i played with AGC THR on 2 different K3's this afternoon. To me both sound more pleasant with AGC THR 2 on strong signals. But digging out the weak ones becomes difficult, the signal sounds mushy. Try it, change AGC THR while listening to a very weak ssb-signal. It becomes more and more readable the closer you get to 5, the default. The signal stands out, even though the noise is higher. YMMV Martin -- 73, DM4iM __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
There's something about Cookie's description of how one can hear noise that makes me think that perhaps some of these "noisy" K3 comments are due to having an expectation that is simply not realistic. I get the impression that the expectation may be that at some point, with a given signal strength, and enough signal to noise ratio, you will hear no noise at all. I know this is false - unless you are using FM and the receiver is locked on that one signal. Even under such a "full quieting" situation, you can still hear lightning crashes through the FM signal if they're strong enough. The only other way that this would happen is if we were removing the noise using DSP techniques, and re-creating the desired signal absent of the noise that will always be there. I have tried such DSP stuff, and what remains does not sound all that good to me, and it needs to be used sparingly. When we're listening to CW or SSB, the level of the signal is constantly changing in amplitude from both fading and just from the constant waveform variance. If the AGC is set to a value (slow) that holds the gain down during the variances, it will mask the apparent amount of noise that we hear. Its not gone, but we don't hear it as much. To confirm this just switch from fast to slow AGC and back to fast on most any receiver and you will notice this phenomena. The point is that there will be noise within your pass band regardless of how narrow it may be and how strong the signal may be that you are listening to. Am I recognizing an unrealistic expectation by users of the K3 (or most any receiver) or am I just misinterpreting this comment? 73, Bob W5OV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of WILLIS COOKE Sent: Saturday, December 19, 2009 11:37 AM To: d...@w3fpr.com; Elecraft Reflector Subject: Re: [Elecraft] [K3] Noisy K3 receiver There are two ways to hear noise that comes from the antenna. If you are hearing it while hearing a CW tone, it is strong enough to compete with the signal and about all you can do is narrow the band width or mentally filter it. If the noise is blanked by the key down signal, but you are hearing it in the pauses it can still be annoying and you can still perceive the receiver to be noisy. In the latter case, changes in the AGC, or RF gain can be effective and reduce the annoyance. This is primarily why I like my slope at about 6 instead of 10. But, I am mostly a CW operator with some SSB. I don't operate AM or FM with my K3 which would certainly have different requirements. Also there is a difference in what is appropriate for weak signal operation or strong signal operation. In a contest situation you repidly switch between strong and weak signals so you probably would prefer a compromise setting. Willis 'Cookie' Cooke K5EWJ From: Don Wilhelm To: elecraft@mailman.qth.net Sent: Sat, December 19, 2009 9:23:08 AM Subject: Re: [Elecraft] [K3] Noisy K3 receiver Maarten (and all), There are two separate noise sources to be considered here, and it is important to separate them. One is the internal receiver noise, and the second is demodulated noise that comes into the receiver via the antenna port. For anyone who suspects that the K3 itself is noisy (because of internal noise), I encourage those owners to do an MDS measurement. If the internal noise is excessive, the MDS will be greatly reduced - MDS is the minimum signal level that can be detected above the receiver noise floor. The Elecraft XG1 or XG2 is an inexpensive signal generator that will do the task - and the instructions for measuring MDS are in the manual. If your K3 is not 'up to par', then that problem can be fixed. OTOH, if the noise is coming into the receiver on the antenna port, there is not much that can be done to eliminate it - it is just like any other "signal" coming in from the antenna. The K3 does offer tools such as the attenuator and AGC adjustments that can better handle than noise. Unfortunately, there is not a "one size fits all" solution because each source of noise is different in its character and amplitude. I cannot comment intelligently to those who are comparing the K3 audio noise output with that of another receiver because I do not have access to the receivers they are comparing. I can only guess that the difference may be due to differences in receiver gain, AGC action, bandpass width, or the shaping of the audio spectrum. Without doing actual measurements, these variables cannot be quantified. 73, Don W3FPR Maarten van Rossum wrote: > I hope that with the help of this topic on the reflector, I too am able to > set my K3 correctly for my circumstances so I too can enjoy noise free > reception. > > _
Re: [Elecraft] [K3] Noisy K3 receiver
There are two ways to hear noise that comes from the antenna. If you are hearing it while hearing a CW tone, it is strong enough to compete with the signal and about all you can do is narrow the band width or mentally filter it. If the noise is blanked by the key down signal, but you are hearing it in the pauses it can still be annoying and you can still perceive the receiver to be noisy. In the latter case, changes in the AGC, or RF gain can be effective and reduce the annoyance. This is primarily why I like my slope at about 6 instead of 10. But, I am mostly a CW operator with some SSB. I don't operate AM or FM with my K3 which would certainly have different requirements. Also there is a difference in what is appropriate for weak signal operation or strong signal operation. In a contest situation you repidly switch between strong and weak signals so you probably would prefer a compromise setting. Willis 'Cookie' Cooke K5EWJ From: Don Wilhelm To: elecraft@mailman.qth.net Sent: Sat, December 19, 2009 9:23:08 AM Subject: Re: [Elecraft] [K3] Noisy K3 receiver Maarten (and all), There are two separate noise sources to be considered here, and it is important to separate them. One is the internal receiver noise, and the second is demodulated noise that comes into the receiver via the antenna port. For anyone who suspects that the K3 itself is noisy (because of internal noise), I encourage those owners to do an MDS measurement. If the internal noise is excessive, the MDS will be greatly reduced - MDS is the minimum signal level that can be detected above the receiver noise floor. The Elecraft XG1 or XG2 is an inexpensive signal generator that will do the task - and the instructions for measuring MDS are in the manual. If your K3 is not 'up to par', then that problem can be fixed. OTOH, if the noise is coming into the receiver on the antenna port, there is not much that can be done to eliminate it - it is just like any other "signal" coming in from the antenna. The K3 does offer tools such as the attenuator and AGC adjustments that can better handle than noise. Unfortunately, there is not a "one size fits all" solution because each source of noise is different in its character and amplitude. I cannot comment intelligently to those who are comparing the K3 audio noise output with that of another receiver because I do not have access to the receivers they are comparing. I can only guess that the difference may be due to differences in receiver gain, AGC action, bandpass width, or the shaping of the audio spectrum. Without doing actual measurements, these variables cannot be quantified. 73, Don W3FPR Maarten van Rossum wrote: > I hope that with the help of this topic on the reflector, I too am able to > set my K3 correctly for my circumstances so I too can enjoy noise free > reception. > > __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
That's an interesting observation and there is an easy way to check it out. If you feed the stereo Line Out signal from your K3 into your sound card while using Spectrogram (a free program) to observe both channels, you should be able to get a direct comparison of the two receivers. Spectrogram will even let you take a jpeg snapshot of the spectrum display. Any chance you might be willing to do that? If you don't want to mess with it, just record some of the audio as a stereo file and I'll run it through Spectrogram for you. Just be sure to have all the same K3 settings (gain, bandwidth, shift, etc) for both receivers and tune both receivers to similar portions of the band. 73, Dave AB7E Richard Ferch wrote: > HB9ANM wrote: > >> what puzzles me is why this topic now suddenly pops up more >> two years after the first K3s appeared in the ham community? There must be >> some good reason why nobody raised the subject before... Until someone >> sparked a tsunami of comments! >> > > Possibly because the problem might exist in only a small percentage of > K3s. For example, my main RX is quiet, but my sub-RX is noisy. Two K3 > receivers in the same box with the same settings and firmware, different > audio performance. Maybe the main receivers in the K3s whose owners > complain about noise have the same problem as my sub-RX, whatever that > problem may happen to be. > > 73, > Rich VE3KI > __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
I can't say that I was ever completely happy with the audio output of the K3. My father was an audiophile and the K3 reminds me a bit of some of the high-end audio stuff that he used to demonstrate to me. It had remarkable detail and clarity but it also revealed things that perhaps were best hidden and made it, to me, a bit tiring to listen to compared to my own budget stereo system. On the K3 CW and data signals sound remarkably pure and distortion free and SSB sounds very clean and open. But on headphones particularly and on some speakers other than the internal speaker I do find the K3 tiring to listen to. This may be due to high frequency "artifacts" that some have mentioned, but I have come to the conclusion that it has more to do with the excessive low frequency roll-off in the K3 audio circuits particularly the headphone circuit. Today, I performed the RF gain calibration procedure, recalibrated the S meter, then experimented with the AGC threshold and slope settings along the lines suggested in this thread. I didn't find it made much difference to the sound of the radio, or even the ability of signals to "pop out" of the noise has been described. I then made some A/B comparisons between the K3 and my FT-817ND, since that was connected up and available. Listening on headphones, the FT-817ND was definitely the most pleasant of the two radios to listen to, and signals seemed to stand clear of the noise better. I then attempted to record this to make some demo MP3 files via the line audio from both radios. The difference, though still noticeable, was less marked than when listening on headphones. As my K3 is connected to its own dedicated sound card, I downloaded Spectran and used this to experiment with the effect of filtering on the received audio. You can play the K3 audio into one sound card and play back the output (optionally filtered by Spectran) to the regular one and listen with headphones plugged into the computer. This convinced me that the K3 is certainly capable of producing very high quality audio. I didn't see any sign of high frequency "artifacts" on the display. A low pass filter coming in anywhere from 2.7KHz or higher didn't make much difference to the sound at all. But changing the position of the high pass filter to allow more bass through made a big subjective difference to the sound. More bass made the audio less tiring and more pleasant to listen to. I have done the KIO3 mod to improve the bass through the line output and the mod on the main board for the speaker output. I still have the original DSP board. Recently I plugged a pair of cheap computer speakers into the rear speaker socket of the K3. Being computer speakers they were powered with a high impedance input so there is less attenuation of low frequencies than when using non-powered 8 ohm speakers. The audio quality was quite pleasant considering the price of the speakers. The audio through headphones plugged into the socket of one of the speakers was also much better than the audio from the same headphones plugged directly into the K3. I agree with others who have said that more information is needed than just "my K3 is noisy". We need to know what they are listening with, what impedance it is, what audio-related mods have been done. I personally think that the excessive attenuation of low frequencies in the K3's audio circuits particularly the headphone output is the major factor in many of the complaints that the K3 sounds tiring. I am not convinced that an add-in LPF will have any effect. What I am concerned about - especially in view of the cost of exchanging the DSP board for those outside the US - is whether the improvements in low frequency output are enough. A lower-cost workaround might be to try some powered computer speakers and use the headphone output on those. Most people will have computer speakers already they can hook up as an experiment, so it would not be difficult to try it. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4191926.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Maarten (and all), There are two separate noise sources to be considered here, and it is important to separate them. One is the internal receiver noise, and the second is demodulated noise that comes into the receiver via the antenna port. For anyone who suspects that the K3 itself is noisy (because of internal noise), I encourage those owners to do an MDS measurement. If the internal noise is excessive, the MDS will be greatly reduced - MDS is the minimum signal level that can be detected above the receiver noise floor. The Elecraft XG1 or XG2 is an inexpensive signal generator that will do the task - and the instructions for measuring MDS are in the manual. If your K3 is not 'up to par', then that problem can be fixed. OTOH, if the noise is coming into the receiver on the antenna port, there is not much that can be done to eliminate it - it is just like any other "signal" coming in from the antenna. The K3 does offer tools such as the attenuator and AGC adjustments that can better handle than noise. Unfortunately, there is not a "one size fits all" solution because each source of noise is different in its character and amplitude. I cannot comment intelligently to those who are comparing the K3 audio noise output with that of another receiver because I do not have access to the receivers they are comparing. I can only guess that the difference may be due to differences in receiver gain, AGC action, bandpass width, or the shaping of the audio spectrum. Without doing actual measurements, these variables cannot be quantified. 73, Don W3FPR Maarten van Rossum wrote: > I hope that with the help of this topic on the reflector, I too am able to > set my K3 correctly for my circumstances so I too can enjoy noise free > reception. > > __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Hi Richard, About I year ago the subject was discussed on the reflector as well. Just like it does now it then caused a lot of discussion too. If I remember it correctly Elecraft came up with a firmware release which provided more low audio response partially because of that discussion on the reflector. Among others, K8ZOA wrote an article about the different parameters of the AGC which helped a lot of people to set up the AGC correctly. It seems to me that now, a year later, that article has dropped to the background and new users seem to struggle with a correct AGC setting. It's certainly is not something new, people have mentioned it before and I like to believe it's still a work in progress. 73, Maarten van Rossum PD2R P.s. This is the article I reffered to: http://www.cliftonlaboratories.com/Documents/Elecraft%20K3%20Transceiver%20AGC%20Parameters%20and%20S-meter.pdf 2009/12/19 Richard Squire - HB9ANM > > Hi Maarten. It is a fact that DSP receivers tend to have a somewhat higher > noise floor. I am certainly not suggesting anybody lost his rights to talk > about it. But what puzzles me is why this topic now suddenly pops up more > two years after the first K3s appeared in the ham community? There must be > some good reason why nobody raised the subject before... Until someone > sparked a tsunami of comments! > > > PD2R wrote: > > > > Correct me if I'm wrong Richard, but are you saying that "the noise", > > whatever color it may be, is something we all have to put up with? And > > since > > 2 years have past, we have lost the right to say anything about it? > > > > > > > - > Richard - HB9ANM > -- > View this message in context: > http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4191276.html > Sent from the [K3] mailing list archive at Nabble.com. > __ > 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
Re: [Elecraft] [K3] Noisy K3 receiver
HB9ANM wrote: > what puzzles me is why this topic now suddenly pops up more > two years after the first K3s appeared in the ham community? There must be > some good reason why nobody raised the subject before... Until someone > sparked a tsunami of comments! Possibly because the problem might exist in only a small percentage of K3s. For example, my main RX is quiet, but my sub-RX is noisy. Two K3 receivers in the same box with the same settings and firmware, different audio performance. Maybe the main receivers in the K3s whose owners complain about noise have the same problem as my sub-RX, whatever that problem may happen to be. 73, Rich VE3KI __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Hi Maarten. It is a fact that DSP receivers tend to have a somewhat higher noise floor. I am certainly not suggesting anybody lost his rights to talk about it. But what puzzles me is why this topic now suddenly pops up more two years after the first K3s appeared in the ham community? There must be some good reason why nobody raised the subject before... Until someone sparked a tsunami of comments! PD2R wrote: > > Correct me if I'm wrong Richard, but are you saying that "the noise", > whatever color it may be, is something we all have to put up with? And > since > 2 years have past, we have lost the right to say anything about it? > > - Richard - HB9ANM -- View this message in context: http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4191276.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
I think what people experience (perceive) is not a noisy receiver. If it were K3's MDS would have to be much worse than other radios :-) It is a combination of the K3's sound character and AGC character. -The "color" of noise defines its annoyance factor. -The AGC setting define how much signals and noise are seperated (how signals "jump" out of the noise or drown in it) Fortunately both are throroughly adjustable in the K3. Wouldn't it be a good idea if Elecraft would gather and mediate information from users about sets they perceive as pleasant sounding radios. I'm quite sure Elecraft could come up with a few setting templates that mimic a certain FT/TS/TT radio if that's what users would like, but it takes time to just sit down and compare A to B. The K3 is highly configurable but many seem to get lost because they don't know how to translate a specific "sound" in AGC/EQ settings, which is quite a task with all variables available. 73' Paul PD0PSB Correct me if I'm wrong Richard, but are you saying that "the noise", whatever color it may be, is something we all have to put up with? And since 2 years have past, we have lost the right to say anything about it? -- View this message in context: http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4191198.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Correct me if I'm wrong Richard, but are you saying that "the noise", whatever color it may be, is something we all have to put up with? And since 2 years have past, we have lost the right to say anything about it? There are a lot off people who find this topic very helpful. You obviously do not and consider it "noise floor". As far as I can tell, nobody is twisting your arm and makes you read this topic so don't read it if it bothers you that much. I hope that with the help of this topic on the reflector, I too am able to set my K3 correctly for my circumstances so I too can enjoy noise free reception. Thank you for your contribution. 2009/12/19 Richard Squire - HB9ANM > > I'll second that, Ian! I'm lucky to live in quite, rural QTH with no > computers around except my own... > So the K3's inherent white/pink or whatever colour noise is certainly > something that can be put up with, as in ANY other DSP rig. Wonder why this > topic suddenly pops up - and seems to be relevant to so many after 2 > years... causing such a "noise floor" on the reflector! I listened to > FT2Ks, > Orions, ... then purchased the K3. I must have had some good reasons. > 73 > > > __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
I'll second that, Ian! I'm lucky to live in quite, rural QTH with no computers around except my own... So the K3's inherent white/pink or whatever colour noise is certainly something that can be put up with, as in ANY other DSP rig. Wonder why this topic suddenly pops up - and seems to be relevant to so many after 2 years... causing such a "noise floor" on the reflector! I listened to FT2Ks, Orions, ... then purchased the K3. I must have had some good reasons. 73 Ian Maude wrote: > > Hi all, > I have been following this thread with interest. My experience is that my > K3 seems noisy at home where my ambient RF noise floor can be anything up > to > s9 at times with the amount of RF producing electrical junk all around me. > However, when I use it at a 'quiet' location such as our DXpedition to > the > Isle of Jura or our contest site, the RX is extremely quiet. This leads > me > to believe that I am simply suffering from a RX with a *lot* of gain. At > home, I simply turn down the RF gain and it is amazing how quickly the > noise > lowers significantly! There is only about 30dB of isolation between > antenna > 1 and antenna 2 off the tuner which does not help the noise floor and as > such I have simply stopped putting an antenna in ant2 for HF, I only have > my > 6m log periodic in there. > I think in a lot of ways we are chasing our tails here. > > 73 Ian > > -- > Ian J Maude, G0VGS > SysOp GB7MBC & HB9DRV-9 DX Clusters > Member RSGB, GQRP 9838, FISTS 14077 | K3 #455 > http://www.amateurradiotraining.org > __ > 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 > > - Richard - HB9ANM -- View this message in context: http://n2.nabble.com/Noisy-K3-receiver-tp4184529p4190894.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
Re: [Elecraft] [K3] Noisy K3 receiver
Hello all! I have read the many comments upon the noisy K3 receiver with interest. I, too, have always thought the K3 somewhat noisy, but that is in comparison to the other receivers I have. The best sound from a modern receiver to me has been from the Ten Tec OMNI VII. When I place the RF gain on that radio to about 25-35%, the noise is gone and the signals are still there, for a true treat of listening without fatigue. When I first got the K3, I was disappointed with the fatiguing hiss or artifacts (definitely higher frequencies) which I experienced. Over the two years of having the K3, though, I have seen gradual improvements while I have learned to adjust the AGC parameters. I added all the mods which had to do with audio, and each one brought a little improvement. Now, somedays I am amazed at how quiet the K3 seems to be, with the signals just popping out of the noise, while other days I still wonder what I need to adjust. I also realize that my hearing, which has a peak at approx. 4000-5000 Hz, is somewhat sensitive to higher pitched noise. I do understand that those who find it tiring to listen to the K3 are honestly reporting their experience. Isn't it wonderful that we now have a radio which allows us to become aware of: 1) A spectrum analysis of our hearing loss/gain so we can make adjustments to compensate for damage, age, etc.; 2) Our opportunity to learn the differences in atmospheric and operating conditions, and the specific AGC requirements for each; 3) The wide range of variability among Amateur operators as to their desires and interests 4) A higher level of technological achievement which opens up the possibility of such discussions as these because of the K3's clarity and reproducibility of signals, which in turn allows us to hear what has never been heard before. The K3 is another step in the advancement of Ham Radio technology. It is not the pinnacle (or will not be there forever, anyway) of achievement, but it is among the best we know today. Tomorrow will be a different story. Meanwhile, let us communicate with what we have, while urging Aptos on to even higher goals. Bill W4ISH __ 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
Re: [Elecraft] [K3] Noisy K3 Receiver
A new noise has recently started appearing at this QTH on 10m, which was previously a quiet band. Normally the S meter would read about S2, but now it reads about S5. This noise, heard through the K3, has a distinct "buzzing" sound. I decided to switch the antenna to the FT-817 in order to record the noise, because the 817 is connected to the default sound card that Windows Recorder will record from. On that radio the noise sounded completely different. The buzz was not audible at all, it was just a sort of "mush". Except for the increased level (the FT-817 S-meter was reading S8 with preamp on) you might think you were listening to band noise. Now why would noise sound different on one radio to another? I'm sure the buzz is really there, coming from some new device a neighbour has acquired, and the K3 isn't making it up. So perhaps the K3 is reproducing the sound of the band as it really is, while the lesser receiver has a lot more intermodulation that is mixing up all the noise which just happens to make it sound less harsh and easier on the ears? I find it hard to believe that the K3 receiver is actually noisy, in the sense that it is generating noise internally that makes it harder to hear weak signals compared to another RX. Those MDS figures can't lie, surely? So why is a new DSP board needed, except to "fudge" the sound so that it doesn't sound as noisy? You aren't going to hear anything with the new board that you wouldn't have heard without it. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/Noisy-K-3-Receiver-tp4173832p4180780.html Sent from the [K3] mailing list archive at Nabble.com. __ 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
