Re: [Elecraft] k3 NR Audio level increase
After thinking further about Steve's question about whether a mic was connected or not, I found the cause of the problem -- line in and line out were connected to a computer sound card, which although powered down, apparently provided enough coupling between line out and line in to drive the VOX when tuning through the carrier with NR on. When doing so the line out level apparently gets very high, at least briefly. The line out level was set to 10, line in gain to 22. With the cables removed from the K3 there is no problem. So it's a result of unintended coupling, it all makes perfect sense now. Thanks Steve! Bob NW8L On Sat, Apr 25, 2009 at 7:30 PM, Bob Cunnings bob.cunni...@gmail.com wrote: Yes, I've noticed the tendency of NR to null out carriers, which is easy to observe when VOX is off. But with VOX on, the phenomenon I'm observing is quite different than that - a wup-wup-wup oscillation with a period of a second or so that may persist for a considerable time after it is triggered by slowly tuning through the carrier. The more aggressive the NR setting, the more vulnerable it seems, but with a strong carrier it can be triggered at any setting. No, I have no microphone connected, and no computer. When this occurs, the red TX indicator does *not* light if K3 is in TEST mode, that's why I hadn't noticed it earlier - I had the rig in TEST mode at the time. Bob NW8L On Sat, Apr 25, 2009 at 7:01 PM, Steve Ellington n...@carolina.rr.com wrote: Bob When in USB/LSB, NR does tend to totally null out carriers. CW does make that wup-wup sound as it's notched out. I'm not sure why NR would be acting as an Auto Notch but this does seem to be the case. Don't know about your red light...Do you have a mic connected? Steve Ellington n...@carolina.rr.com - Original Message - From: Bob Cunnings bob.cunni...@gmail.com To: Elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 7:39 PM Subject: Re: [Elecraft] k3 NR Audio level increase Bob NW8L On Sat, Apr 25, 2009 at 3:20 PM, Bob Cunnings bob.cunni...@gmail.com wrote: Apparently NR *is* upstream of AGC, since a while back NR was disallowed unless AGC was enabled [1] in order, according to K2VCO, to prevent instability [2]. By the way, I can observe this instability (a wup-wup oscillation) in LSB/USB modes with an S9 carrier, and AGC settings on the light side (high threshold, low slope, with THR=8 and SLP=0 being the extreme). I ran into this tuning through shortwave BC stations with NR enabled with THR and SLP set to 5. I'm using firmware version 3.11. What seems odd to me is that although I can reproduce the audio level increase cases observed by others when NR is enabled, the S-meter indication doesn't change - I suppose that the S-meter pickoff point is upstream of NR? On the flip side you mention, if notch filtering was before AGC as you wish, would you expect the S-meter indication to change when the notch filter is active? Bob NW8L [1] http://www.mail-archive.com/elecraft@mailman.qth.net/msg58245.html [2] http://www.mail-archive.com/elecraft@mailman.qth.net/msg60930.html On Sat, Apr 25, 2009 at 12:55 PM, Joe Subich, W4TV li...@subich.com wrote: It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV __ 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] k3 NR Audio level increase
I don't normally make comments on these subjects.. But I have to say, the one reason that I bought my K3, was because when I turn on the NR with a weak signal, and a S5 to S7 noise level (which is what I normally have at my QTH) the CW underneath the noise pops up, gets louder, and I can actually work it! Why would I want this feature changed? Isn't the idea to increase (or enhance as Lyle says) the signal your trying to listen to, while at the same time suppressing the noise below it. I would much rather have to turn down the volume control, then have to wish I was able to turn it up. It seems to me that most of the people with the Audio that cleans out their ears is due to the fact they have uncontrolled AGC levels due to very high Thresholds and very low slopes. I belive if you turn your threshold on a little sooner, this could be avoided. At least from what I've found. As for the meter not reflecting the change in audio level when you turn on the NR. This is a Positive, not a negative. How can you give a proper RST report if you can't even see the pre-effected signal strength? This is exactly the problem that the people using the FT-2000 are having. They have now had to tune their sub receiver to the same freq. as the main, Just to read that non DSP affected S meter. Granted, every user is different, but in my opinion, the NR works just as it should. Let let that be noted Wayne. Michael N6MQL _ Rediscover Hotmail®: Now available on your iPhone or BlackBerry http://windowslive.com/RediscoverHotmail?ocid=TXT_TAGLM_WL_HM_Rediscover_Mobile2_042009 __ 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] k3 NR Audio level increase
I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2702048.html Sent from the Elecraft 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 NR Audio level increase
Terry I agree, it is an effect I have recently noticed. I have not had my K3 very long so I am not quite familiar with all the various options available so I was thinking it was something I have done. A quick check using Speclab indicates about a 20dB increase. Pete G3OBV From: G4POP tge...@btinternet.com To: elecraft@mailman.qth.net Sent: Saturday, 25 April, 2009 9:03:53 AM Subject: [Elecraft] k3 NR Audio level increase I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2702048.html Sent from the Elecraft 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 NR Audio level increase
Terry, I do not experience anything like that on my K3. What NR parameters are you using? Are you attempting to use NR at a narrow bandwidth when this occurs? If so, I can understand why that might occur. Lyle has explained previously that the NR is implemented in the K3 as signal enhancement rather than a strict noise reduction. In other words, the passband is examined for content that correlates, and the result is amplified. If the bandwidth is narrow, it is possible that the entire passband content (including noise) will appear to be a signal. 73, Don W3FPR G4POP wrote: I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP __ 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 NR Audio level increase
Checked again the NB on CW and SSB on both rigs with 3.11. I do not see this problem at all. Is it possible the AGC setup that does this? 73, N2TK, Tony #311 #1435 -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of G4POP Sent: Saturday, April 25, 2009 4:04 AM To: elecraft@mailman.qth.net Subject: [Elecraft] k3 NR Audio level increase I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2702048.html Sent from the Elecraft 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 NR Audio level increase
N2TK wrote: Checked again the NB on CW and SSB on both rigs with 3.11. I do not see this problem at all. Is it possible the AGC setup that does this? Most likely it's due to setting RX EQ to positive settings for some bands: http://www.mail-archive.com/elecraft@mailman.qth.net/msg71174.html 73, Bill -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2709171.html Sent from the Elecraft 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 NR Audio level increase
Don, Try this: 1. Set mode to CW, BW to 2.00, RX EQ = flat. 2. With no signal tuned in, hold NR and set to F4-4. Tap NR twice to turn off NR. 3. Tune in an S9 signal, or better yet, use a signal generator (I use an XG2). 4. Set RF gain to max, AF gain for a comfortable volume. 5. Tap NR to turn on noise reduction. (You might want to keep one hand on the AF gain control :-) On my K3 (with FW 3.11), turning on NR under these conditions boosts the audio output voltage by 17.2 dB according to the built-in AFV meter. Using less aggressive NR parameters results in less of a boost, down to 6.3 dB at F1-1. Now tune in a weak signal (say, S3) and repeat the steps. The boost is still there, but very much reduced (On my rig at S3 and NR=F4-4, the boost is 6.3 dB, at NR=F1-1 it's 1.4 dB) Now imagine trying to copy a signal that rapidly fades between S3 and S9 with NR on. 73 -- Joe KB8AP On Apr 25, 2009, at 4:35 AM, Don Wilhelm wrote: Terry, I do not experience anything like that on my K3. What NR parameters are you using? [...] 73, Don W3FPR G4POP wrote: I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. [...] Terry G4POP __ 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 NR Audio level increase
Joe, following your instructions, I cannot duplicate this on my rig listening to a S-9 signal. I do find that if AGC-THR is set below 5, the audio drops significantly when initiating NR at my preferred setting, 2-1. Decreasing the AGC SLP increases the audio with NR engaged. Gary W7TEA Don, Try this: 1. Set mode to CW, BW to 2.00, RX EQ = flat. 2. With no signal tuned in, hold NR and set to F4-4. Tap NR twice to turn off NR. -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2709775.html Sent from the Elecraft 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 NR Audio level increase
- Original Message - From: Joe Planisky jp...@jeffnet.org To: d...@w3fpr.com; Elecraft@mailman.qth.net Cc: G4POP tge...@btinternet.com Sent: Saturday, April 25, 2009 2:58 PM Subject: Re: [Elecraft] k3 NR Audio level increase 1. Set mode to CW, BW to 2.00 --- If the snr is marginal, why would you set BW = 2.0? Dave Hachadorian, K6LL Yuma, AZ . __ 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 NR Audio level increase
The settings and steps are intended to demonstrate the issue, they're not necessarily typical operating settings. Don had suggested that perhaps the cause was related to using NR with a narrow bandwidth. I wanted to demonstrate that it happens at wide bandwidth as well. 73 -- Joe KB8AP On Apr 25, 2009, at 8:21 AM, Dave Hachadorian wrote: If the snr is marginal, why would you set BW = 2.0? Dave Hachadorian, K6LL Yuma, AZ __ 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 NR Audio level increase
I have the problem also for some time, it is signal strength dependent, the signal must be loud enough and when you hit the NR function with a high setting the audio increases greatly,Easiest way to prove it is with a variable strength signal fed into the receiver and setting the NR to a setting if 4.Will clean your ears out for sure. It does it on other settings as well but less of an audio increase. By the way thats not how an audio peak filter works if thats what its trying to simulate. Merv KH7C Checked again the NB on CW and SSB on both rigs with 3.11. I do not see this problem at all. Is it possible the AGC setup that does this? 73, N2TK, Tony #311 #1435 -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of G4POP Sent: Saturday, April 25, 2009 4:04 AM To: elecraft@mailman.qth.net Subject: [Elecraft] k3 NR Audio level increase I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP __ 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 NR Audio level increase
Good catch, Gary. AGC settings are the missing piece and probably why some people aren't seeing this. With an S9 signal, NR=F4-4, BW=2.00, I get the following results for different settings of AGC THR and AGC SLP when NR is engaged: THR=2, SLP= 0 +10.0 dB THR=2, SLP= 5 + 2.7 dB THR=2, SLP=10 - 6.0 dB THR=2, SLP=15 -15.5 dB THR=4, SLP= 0 +15.2 dB THR=4, SLP= 5 + 9.6 dB THR=4, SLP=10 + 3.6 dB THR=4, SLP=15 - 3.8 dB THR=6, SLP= 0 +16.6 dB THR=6, SLP= 5 +13.3 dB THR=6, SLP=10 + 7.9 dB THR=6, SLP=15 + 1.5 dB THR=8, SLP= 0 +18.3 dB THR=8, SLP= 5 +15.6 dB THR=8, SLP=10 +11.7 dB THR=8, SLP=15 + 7.0 db 73 -- Joe KB8AP On Apr 25, 2009, at 8:21 AM, W7TEA wrote: Joe, following your instructions, I cannot duplicate this on my rig listening to a S-9 signal. I do find that if AGC-THR is set below 5, the audio drops significantly when initiating NR at my preferred setting, 2-1. Decreasing the AGC SLP increases the audio with NR engaged. Gary W7TEA __ 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 NR Audio level increase
So where's the problem? Everything seems to be working properly. With a high THR and low SLP, louder signals are LOUD and NR just helps make it more obvious because there's not so much noise to distract your hearing. Remember, AGC used to be called AVC Automatic Volume Control, back in the old days. If you choose a high threshold, THR, that means that AVC does almost nothing. AVC becomes MVW, manual volume control, Meaning knobs must be turned (AF). Steve Ellington n...@carolina.rr.com - Original Message - From: Joe Planisky jp...@jeffnet.org To: W7TEA gt...@mac.com Cc: elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 1:22 PM Subject: Re: [Elecraft] k3 NR Audio level increase Good catch, Gary. AGC settings are the missing piece and probably why some people aren't seeing this. With an S9 signal, NR=F4-4, BW=2.00, I get the following results for different settings of AGC THR and AGC SLP when NR is engaged: THR=2, SLP= 0 +10.0 dB THR=2, SLP= 5 + 2.7 dB THR=2, SLP=10 - 6.0 dB THR=2, SLP=15 -15.5 dB THR=4, SLP= 0 +15.2 dB THR=4, SLP= 5 + 9.6 dB THR=4, SLP=10 + 3.6 dB THR=4, SLP=15 - 3.8 dB THR=6, SLP= 0 +16.6 dB THR=6, SLP= 5 +13.3 dB THR=6, SLP=10 + 7.9 dB THR=6, SLP=15 + 1.5 dB THR=8, SLP= 0 +18.3 dB THR=8, SLP= 5 +15.6 dB THR=8, SLP=10 +11.7 dB THR=8, SLP=15 + 7.0 db 73 -- Joe KB8AP On Apr 25, 2009, at 8:21 AM, W7TEA wrote: Joe, following your instructions, I cannot duplicate this on my rig listening to a S-9 signal. I do find that if AGC-THR is set below 5, the audio drops significantly when initiating NR at my preferred setting, 2-1. Decreasing the AGC SLP increases the audio with NR engaged. Gary W7TEA __ 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 NR Audio level increase
I am talking about SSB with a bandwidth between 1k and 3.5k ( I have the 250, 1k, 1.8k, 2.7k 6K filters installed) No mater what NR setting is used I get the same effect to a lesser or grater degree Strange that some of you have this problem while others do not? Terry N2TK wrote: Checked again the NB on CW and SSB on both rigs with 3.11. I do not see this problem at all. Is it possible the AGC setup that does this? 73, N2TK, Tony #311 #1435 -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of G4POP Sent: Saturday, April 25, 2009 4:04 AM To: elecraft@mailman.qth.net Subject: [Elecraft] k3 NR Audio level increase I see that the dramatic increase in audio level when NR is turned on has been mentioned a couple of times but I can find no solution for this mentioned in the forum and the latest firmware 3.11 has not cured it. At this point I find NR totally un-usable unless I want to risk perforated ear drums! Terry G4POP -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2702048.html Sent from the Elecraft 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 -- View this message in context: http://n2.nabble.com/k3-NR-Audio-level-increase-tp2702048p2711713.html Sent from the Elecraft 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 NR Audio level increase
So where's the problem? Everything seems to be working properly. With a high THR and low SLP, louder signals are LOUD and NR just helps make it more obvious because there's not so much noise to distract your hearing. It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Steve Ellington Sent: Saturday, April 25, 2009 2:00 PM To: Joe Planisky; W7TEA Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] k3 NR Audio level increase So where's the problem? Everything seems to be working properly. With a high THR and low SLP, louder signals are LOUD and NR just helps make it more obvious because there's not so much noise to distract your hearing. Remember, AGC used to be called AVC Automatic Volume Control, back in the old days. If you choose a high threshold, THR, that means that AVC does almost nothing. AVC becomes MVW, manual volume control, Meaning knobs must be turned (AF). Steve Ellington n...@carolina.rr.com - Original Message - From: Joe Planisky jp...@jeffnet.org To: W7TEA gt...@mac.com Cc: elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 1:22 PM Subject: Re: [Elecraft] k3 NR Audio level increase Good catch, Gary. AGC settings are the missing piece and probably why some people aren't seeing this. With an S9 signal, NR=F4-4, BW=2.00, I get the following results for different settings of AGC THR and AGC SLP when NR is engaged: THR=2, SLP= 0 +10.0 dB THR=2, SLP= 5 + 2.7 dB THR=2, SLP=10 - 6.0 dB THR=2, SLP=15 -15.5 dB THR=4, SLP= 0 +15.2 dB THR=4, SLP= 5 + 9.6 dB THR=4, SLP=10 + 3.6 dB THR=4, SLP=15 - 3.8 dB THR=6, SLP= 0 +16.6 dB THR=6, SLP= 5 +13.3 dB THR=6, SLP=10 + 7.9 dB THR=6, SLP=15 + 1.5 dB THR=8, SLP= 0 +18.3 dB THR=8, SLP= 5 +15.6 dB THR=8, SLP=10 +11.7 dB THR=8, SLP=15 + 7.0 db 73 -- Joe KB8AP On Apr 25, 2009, at 8:21 AM, W7TEA wrote: Joe, following your instructions, I cannot duplicate this on my rig listening to a S-9 signal. I do find that if AGC-THR is set below 5, the audio drops significantly when initiating NR at my preferred setting, 2-1. Decreasing the AGC SLP increases the audio with NR engaged. Gary W7TEA __ 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
Re: [Elecraft] k3 NR Audio level increase
Joe, I tried your suggested settings, and yes I found an increase in audio volume. I also observed that the NR worked as a squelch at that aggressive setting. I normally use F1-3 or F1-4 for NR and have no problem. I don't use NR when attempting to copy a weak signal. When the weak signal is down in the noise level, the NR algorithm cannot distinguish between the noise and the signal with certainty. My ears do a better job despite the noise, so I turn NR off when digging for the weak ones. 73, Don W3FPR Joe Planisky wrote: Don, Try this: 1. Set mode to CW, BW to 2.00, RX EQ = flat. 2. With no signal tuned in, hold NR and set to F4-4. Tap NR twice to turn off NR. 3. Tune in an S9 signal, or better yet, use a signal generator (I use an XG2). 4. Set RF gain to max, AF gain for a comfortable volume. 5. Tap NR to turn on noise reduction. (You might want to keep one hand on the AF gain control :-) On my K3 (with FW 3.11), turning on NR under these conditions boosts the audio output voltage by 17.2 dB according to the built-in AFV meter. Using less aggressive NR parameters results in less of a boost, down to 6.3 dB at F1-1. Now tune in a weak signal (say, S3) and repeat the steps. The boost is still there, but very much reduced (On my rig at S3 and NR=F4-4, the boost is 6.3 dB, at NR=F1-1 it's 1.4 dB) Now imagine trying to copy a signal that rapidly fades between S3 and S9 with NR on. 73 -- Joe KB8AP __ 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 NR Audio level increase
Apparently NR *is* upstream of AGC, since a while back NR was disallowed unless AGC was enabled [1] in order, according to K2VCO, to prevent instability [2]. By the way, I can observe this instability (a wup-wup oscillation) in LSB/USB modes with an S9 carrier, and AGC settings on the light side (high threshold, low slope, with THR=8 and SLP=0 being the extreme). I ran into this tuning through shortwave BC stations with NR enabled with THR and SLP set to 5. I'm using firmware version 3.11. What seems odd to me is that although I can reproduce the audio level increase cases observed by others when NR is enabled, the S-meter indication doesn't change - I suppose that the S-meter pickoff point is upstream of NR? On the flip side you mention, if notch filtering was before AGC as you wish, would you expect the S-meter indication to change when the notch filter is active? Bob NW8L [1] http://www.mail-archive.com/elecraft@mailman.qth.net/msg58245.html [2] http://www.mail-archive.com/elecraft@mailman.qth.net/msg60930.html On Sat, Apr 25, 2009 at 12:55 PM, Joe Subich, W4TV li...@subich.com wrote: It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV __ 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 NR Audio level increase
Heh. My voltmeter's hearing doesn't tend to get distracted by noise. On Apr 25, 2009, at 11:00 AM, Steve Ellington wrote: So where's the problem? Everything seems to be working properly. With a high THR and low SLP, louder signals are LOUD and NR just helps make it more obvious because there's not so much noise to distract your hearing. Remember, AGC used to be called AVC Automatic Volume Control, back in the old days. If you choose a high threshold, THR, that means that AVC does almost nothing. AVC becomes MVW, manual volume control, Meaning knobs must be turned (AF). Steve Ellington n...@carolina.rr.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 NR Audio level increase
Interesting. For CW I always use the NR to dig out the weak ones. The effect is amazing. I believe the reason we all see this differently is due to AGC settings. THR, SLP etc. really affect the NR. Steve Ellington n...@carolina.rr.com - Original Message - From: Don Wilhelm w3...@embarqmail.com To: Joe Planisky jp...@jeffnet.org Cc: Elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 5:14 PM Subject: Re: [Elecraft] k3 NR Audio level increase Joe, I tried your suggested settings, and yes I found an increase in audio volume. I also observed that the NR worked as a squelch at that aggressive setting. I normally use F1-3 or F1-4 for NR and have no problem. I don't use NR when attempting to copy a weak signal. When the weak signal is down in the noise level, the NR algorithm cannot distinguish between the noise and the signal with certainty. My ears do a better job despite the noise, so I turn NR off when digging for the weak ones. 73, Don W3FPR Joe Planisky wrote: Don, Try this: 1. Set mode to CW, BW to 2.00, RX EQ = flat. 2. With no signal tuned in, hold NR and set to F4-4. Tap NR twice to turn off NR. 3. Tune in an S9 signal, or better yet, use a signal generator (I use an XG2). 4. Set RF gain to max, AF gain for a comfortable volume. 5. Tap NR to turn on noise reduction. (You might want to keep one hand on the AF gain control :-) On my K3 (with FW 3.11), turning on NR under these conditions boosts the audio output voltage by 17.2 dB according to the built-in AFV meter. Using less aggressive NR parameters results in less of a boost, down to 6.3 dB at F1-1. Now tune in a weak signal (say, S3) and repeat the steps. The boost is still there, but very much reduced (On my rig at S3 and NR=F4-4, the boost is 6.3 dB, at NR=F1-1 it's 1.4 dB) Now imagine trying to copy a signal that rapidly fades between S3 and S9 with NR on. 73 -- Joe KB8AP __ 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 NR Audio level increase
Steve, My AGC THR is 008 and the SLP is 02 if that makes any difference to your conclusions. FWIW, a narrow bandwidth with NR off is best for weak signal reception for me. The narrow bandwidth itself reduces the noise substantially and my ears have to do the rest. 73, Don W3FPR Steve Ellington wrote: Interesting. For CW I always use the NR to dig out the weak ones. The effect is amazing. I believe the reason we all see this differently is due to AGC settings. THR, SLP etc. really affect the NR. Steve Ellington n...@carolina.rr.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 NR Audio level increase
I've only just now noticed that the oscillation when NR is enabled that I hear when tuning through an S9 carrier in USB/LSB happens only when VOX is enabled. In fact, I just now noticed that the red TX indicator is illuminated when this happens - although there is no indication of power out on either the K3 or the outboard power meter. So with AGC SLP=5, THR=5, NR enabled, VOX enabled, tuning through S9 carrier triggers this on USB/LSB, but not CW. Very strange. Bob NW8L On Sat, Apr 25, 2009 at 3:20 PM, Bob Cunnings bob.cunni...@gmail.com wrote: Apparently NR *is* upstream of AGC, since a while back NR was disallowed unless AGC was enabled [1] in order, according to K2VCO, to prevent instability [2]. By the way, I can observe this instability (a wup-wup oscillation) in LSB/USB modes with an S9 carrier, and AGC settings on the light side (high threshold, low slope, with THR=8 and SLP=0 being the extreme). I ran into this tuning through shortwave BC stations with NR enabled with THR and SLP set to 5. I'm using firmware version 3.11. What seems odd to me is that although I can reproduce the audio level increase cases observed by others when NR is enabled, the S-meter indication doesn't change - I suppose that the S-meter pickoff point is upstream of NR? On the flip side you mention, if notch filtering was before AGC as you wish, would you expect the S-meter indication to change when the notch filter is active? Bob NW8L [1] http://www.mail-archive.com/elecraft@mailman.qth.net/msg58245.html [2] http://www.mail-archive.com/elecraft@mailman.qth.net/msg60930.html On Sat, Apr 25, 2009 at 12:55 PM, Joe Subich, W4TV li...@subich.com wrote: It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV __ 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 NR Audio level increase
I believe Bill W4ZV hit it on the head with his comment, a couple messages back (ref. below) I was having this problem until I adjusted my RX EQ so the desired CW freq. was at zero or +1, and not higher. Now it's not a problem. Windy KM5Q Most likely it's due to setting RX EQ to positive settings for some bands: http://www.mail-archive.com/elecraft@mailman.qth.net/msg71174.html 73, Bill __ 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 NR Audio level increase
Bob When in USB/LSB, NR does tend to totally null out carriers. CW does make that wup-wup sound as it's notched out. I'm not sure why NR would be acting as an Auto Notch but this does seem to be the case. Don't know about your red light...Do you have a mic connected? Steve Ellington n...@carolina.rr.com - Original Message - From: Bob Cunnings bob.cunni...@gmail.com To: Elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 7:39 PM Subject: Re: [Elecraft] k3 NR Audio level increase I've only just now noticed that the oscillation when NR is enabled that I hear when tuning through an S9 carrier in USB/LSB happens only when VOX is enabled. In fact, I just now noticed that the red TX indicator is illuminated when this happens - although there is no indication of power out on either the K3 or the outboard power meter. So with AGC SLP=5, THR=5, NR enabled, VOX enabled, tuning through S9 carrier triggers this on USB/LSB, but not CW. Very strange. Bob NW8L On Sat, Apr 25, 2009 at 3:20 PM, Bob Cunnings bob.cunni...@gmail.com wrote: Apparently NR *is* upstream of AGC, since a while back NR was disallowed unless AGC was enabled [1] in order, according to K2VCO, to prevent instability [2]. By the way, I can observe this instability (a wup-wup oscillation) in LSB/USB modes with an S9 carrier, and AGC settings on the light side (high threshold, low slope, with THR=8 and SLP=0 being the extreme). I ran into this tuning through shortwave BC stations with NR enabled with THR and SLP set to 5. I'm using firmware version 3.11. What seems odd to me is that although I can reproduce the audio level increase cases observed by others when NR is enabled, the S-meter indication doesn't change - I suppose that the S-meter pickoff point is upstream of NR? On the flip side you mention, if notch filtering was before AGC as you wish, would you expect the S-meter indication to change when the notch filter is active? Bob NW8L [1] http://www.mail-archive.com/elecraft@mailman.qth.net/msg58245.html [2] http://www.mail-archive.com/elecraft@mailman.qth.net/msg60930.html On Sat, Apr 25, 2009 at 12:55 PM, Joe Subich, W4TV li...@subich.com wrote: It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV __ 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 NR Audio level increase
My test results were obtained with all RX EQ setting set to 0. 73 -- Joe KB8AP On Apr 25, 2009, at 5:38 PM, KM5Q wrote: I believe Bill W4ZV hit it on the head with his comment, a couple messages back (ref. below) I was having this problem until I adjusted my RX EQ so the desired CW freq. was at zero or +1, and not higher. Now it's not a problem. Windy KM5Q Most likely it's due to setting RX EQ to positive settings for some bands: http://www.mail-archive.com/elecraft@mailman.qth.net/msg71174.html 73, Bill __ 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 NR Audio level increase
Yes, I've noticed the tendency of NR to null out carriers, which is easy to observe when VOX is off. But with VOX on, the phenomenon I'm observing is quite different than that - a wup-wup-wup oscillation with a period of a second or so that may persist for a considerable time after it is triggered by slowly tuning through the carrier. The more aggressive the NR setting, the more vulnerable it seems, but with a strong carrier it can be triggered at any setting. No, I have no microphone connected, and no computer. When this occurs, the red TX indicator does *not* light if K3 is in TEST mode, that's why I hadn't noticed it earlier - I had the rig in TEST mode at the time. Bob NW8L On Sat, Apr 25, 2009 at 7:01 PM, Steve Ellington n...@carolina.rr.com wrote: Bob When in USB/LSB, NR does tend to totally null out carriers. CW does make that wup-wup sound as it's notched out. I'm not sure why NR would be acting as an Auto Notch but this does seem to be the case. Don't know about your red light...Do you have a mic connected? Steve Ellington n...@carolina.rr.com - Original Message - From: Bob Cunnings bob.cunni...@gmail.com To: Elecraft@mailman.qth.net Sent: Saturday, April 25, 2009 7:39 PM Subject: Re: [Elecraft] k3 NR Audio level increase I've only just now noticed that the oscillation when NR is enabled that I hear when tuning through an S9 carrier in USB/LSB happens only when VOX is enabled. In fact, I just now noticed that the red TX indicator is illuminated when this happens - although there is no indication of power out on either the K3 or the outboard power meter. So with AGC SLP=5, THR=5, NR enabled, VOX enabled, tuning through S9 carrier triggers this on USB/LSB, but not CW. Very strange. Bob NW8L On Sat, Apr 25, 2009 at 3:20 PM, Bob Cunnings bob.cunni...@gmail.com wrote: Apparently NR *is* upstream of AGC, since a while back NR was disallowed unless AGC was enabled [1] in order, according to K2VCO, to prevent instability [2]. By the way, I can observe this instability (a wup-wup oscillation) in LSB/USB modes with an S9 carrier, and AGC settings on the light side (high threshold, low slope, with THR=8 and SLP=0 being the extreme). I ran into this tuning through shortwave BC stations with NR enabled with THR and SLP set to 5. I'm using firmware version 3.11. What seems odd to me is that although I can reproduce the audio level increase cases observed by others when NR is enabled, the S-meter indication doesn't change - I suppose that the S-meter pickoff point is upstream of NR? On the flip side you mention, if notch filtering was before AGC as you wish, would you expect the S-meter indication to change when the notch filter is active? Bob NW8L [1] http://www.mail-archive.com/elecraft@mailman.qth.net/msg58245.html [2] http://www.mail-archive.com/elecraft@mailman.qth.net/msg60930.html On Sat, Apr 25, 2009 at 12:55 PM, Joe Subich, W4TV li...@subich.com wrote: It's not working as it should ... there should be no volume change when engaging NR. Noise reduction should work on the audio AFTER AGC. If anything, the test results below should show a very slight drop with NR due to the removal of the unwanted (broadband) components but the peak level should not change. This NR problem is the flip side of the issue with the notch filter ... Notch is working AFTER the AGC where it should work before AGC while NR is working before the AGC where it should work AFTER the AGC. 73, ... Joe, W4TV __ 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
