Re: [Elecraft] Noise Blankers
In addition to the hard limiter Elecraft provided threshold and slope controls in the AGC system. On 9/3/2017 4:04 PM, Ron D'Eau Claire wrote: The advantage of controlling the gain manually is not an "old wife's tale". Rather, it's clearly just a technique that is not for everyone. AGC will reduce the gain according to the strongest signal inside the I.F. passband. Manually riding the "RF" gain ensures that a very weak signal is not affected by a strong signal that is also inside the I.F. passband. Of course that means your ears could be blasted by that strong signal, which is why Wayne included a hard limiter that can be enabled to chop such a signal down to size, making it no louder than the weak signal we want to copy. __ 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
Re: [Elecraft] Noise Blankers
Ron, you are 100% on the money.. I was thinking about how I wanted to explain the same thing.. thanks.. Fred Fred Moore email: f...@fmeco.com wd8...@gmail.com phone: 321-217-8699 On 9/3/17 7:04 PM, Ron D'Eau Claire wrote: > The advantage of controlling the gain manually is not an "old wife's tale". > Rather, it's clearly just a technique that is not for everyone. > > AGC will reduce the gain according to the strongest signal inside the I.F. > passband. Manually riding the "RF" gain ensures that a very weak signal is > not affected by a strong signal that is also inside the I.F. passband. Of > course that means your ears could be blasted by that strong signal, which is > why Wayne included a hard limiter that can be enabled to chop such a signal > down to size, making it no louder than the weak signal we want to copy. > > It has become a moot point for many operators today who cannot read CW if > they are hearing two or three (or more) signals within the I.F. passband all > at the same time. For them, it's essential to have enough I.F. selectivity to > isolate one signal and so AGC is just fine. > > But some of us have a lifetime of experience sorting out multiple signals > with our gray matter between the ears and prefer to continue to do so -- > probably until we all become SKs. > > 73, Ron AC7AC > > > > -Original Message- > From: elecraft-boun...@mailman.qth.net > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart > Sent: Sunday, September 3, 2017 3:00 PM > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] Noise Blankers > > Just a couple of points. > > In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's > not the audio gain gain control." > > The "RF" gain control operates on the i-f amplifier, which is after the > analog noise blanker. In this regard, it is little different from AGC, which > operates on exactly the same circuitry. Why some people believe that they are > better at controlling i-f gain than the AGC system does is beyond me, but old > wife's tales die hard. If this is hard to fathom, watch the S meter as you > reduce "RF" > gain. The reading increases, no different from letting the AGC do it. > > Attenuation is a different matter. It operates at RF and is a viable tool. > > About noise blanking, I think I had a little to say about that almost 40 years > ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf > > Wes N7WS > > __ > 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 f...@fmeco.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Noise Blankers
The advantage of controlling the gain manually is not an "old wife's tale". Rather, it's clearly just a technique that is not for everyone. AGC will reduce the gain according to the strongest signal inside the I.F. passband. Manually riding the "RF" gain ensures that a very weak signal is not affected by a strong signal that is also inside the I.F. passband. Of course that means your ears could be blasted by that strong signal, which is why Wayne included a hard limiter that can be enabled to chop such a signal down to size, making it no louder than the weak signal we want to copy. It has become a moot point for many operators today who cannot read CW if they are hearing two or three (or more) signals within the I.F. passband all at the same time. For them, it's essential to have enough I.F. selectivity to isolate one signal and so AGC is just fine. But some of us have a lifetime of experience sorting out multiple signals with our gray matter between the ears and prefer to continue to do so -- probably until we all become SKs. 73, Ron AC7AC -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart Sent: Sunday, September 3, 2017 3:00 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Noise Blankers Just a couple of points. In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's not the audio gain gain control." The "RF" gain control operates on the i-f amplifier, which is after the analog noise blanker. In this regard, it is little different from AGC, which operates on exactly the same circuitry. Why some people believe that they are better at controlling i-f gain than the AGC system does is beyond me, but old wife's tales die hard. If this is hard to fathom, watch the S meter as you reduce "RF" gain. The reading increases, no different from letting the AGC do it. Attenuation is a different matter. It operates at RF and is a viable tool. About noise blanking, I think I had a little to say about that almost 40 years ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf Wes N7WS __ 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
Re: [Elecraft] Noise Blankers
On 03/09/17 20:38, Wes Stewart wrote: > The K3S blanker is slightly better than > useless. When I set it aggressive enough to be audibly useful, FT8 > decodes multiple signals at 120 Hz intervals, which upsets sequencing. That's an inevitable consequence of how a noise blanker works. It removes power line noise by muting reception 120 (or 100) times a second, corresponding to peaks in the power line voltage when the arcing occurs. If you chop an audio tone up at 120 Hz, you are amplitude modulating the tone with a 120 Hz waveform. That produces sidebands either side of the tone 'carrier'. This is why you should never use a noise blanker with FT8 and similar modes. The best way to use a rig with WSJT-X is, generally speaking, to make the computer do as much as possible and make the rig do as little as possible. Treat it more or less as a dumb transverter. Don't use the noise blanker, don't reduce the bandwidth below about 2.5 kHz, don't use the notch filter. WSJT-X's decoder works best if you just get the level about right and let it deal with the QRM. 73, Richard G4DYA __ 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
Re: [Elecraft] Noise Blankers
Just a couple of points. In the K3(S) there is no "RF Gain" control unless by RF gain you mean "It's not the audio gain gain control." The "RF" gain control operates on the i-f amplifier, which is after the analog noise blanker. In this regard, it is little different from AGC, which operates on exactly the same circuitry. Why some people believe that they are better at controlling i-f gain than the AGC system does is beyond me, but old wife's tales die hard. If this is hard to fathom, watch the S meter as you reduce "RF" gain. The reading increases, no different from letting the AGC do it. Attenuation is a different matter. It operates at RF and is a viable tool. About noise blanking, I think I had a little to say about that almost 40 years ago: http://k6mhe.com/n7ws/Noise_Blanker.pdf Wes N7WS On 9/3/2017 1:48 PM, Bob McGraw K4TAX wrote: Depending the type of noise, for repetitive pulse type noise only, the Noise Blanker does it job. Now one must understand that all pulse noise is not alike. Therefore, different values of NB, both with the IF values and with DSP values, will require some adjustments. If the noise is not repetitive then the NB is not the better choice but the NR is the better choice. Again, depending on they type of noise, certain combinations of NR values will be necessary. Yes, that is correct in that the Noise Reduction function is not available or can not be activated in the DATA mode. However the Noise Blanker can be used in the DATA mode. Again, the Noise Blanker is for repetitive pulse type noise. I've spoken with many hams and find their understanding of Noise Reduction being described as often does not work as expected. Further discussion seems to indicate they want NENoise Elimination. Well, NRNoise Reduction does in fact work when the values are selected based on the type of broad noise spectrum being encountered. NR has very little effect on pulse type noise. One fact not clearly understood, is that most hams operate with too much RF Gain. Thus the correct application of ATTENUATION and RF Gain reduction will greatly improve receiver performance in the face of noise. Optimizing receiver gain compared to band noise and the noise floor of the receiver is explained in a quote from Rob Sherwood, Sherwood Engineering: "If receiver noise floor is 10 dB below band noise, the receiver is contributing less than 0.5 dB of the total noise. Band noise varies by band over 30 dB, 160-10 meters. It also varies by direction and time of day, plus what the sun is doing. In an noisy urban environment it is anybody's guess as to your band noise level. A simple test is to see how much the noise coming out your speaker increases when you switch between a dummy load and your antenna, when tuned to a dead spot on the band. Example on 10 meters at my rural QTH, IC-756 Pro III: preamp OFF, noise goes up 3 dB. That means the receiver is contributing half the noise. Preamp 1 ON, band noise goes up 9.5 dB. Almost all legacy receivers are designed for 10 meters, and attenuation is desirable on the low HF bands." In Rob's first statement, how do we get the band noise to be 10 dB above receiver noise? Use Attenuation and RF Gain reduction. As an example, if receiver noise floor is -130 dBm and the band noise, no signal, is S-5 or -97 dBm, the difference being 33 dB. This would then indicate one should employ 15 dB of Attenuation and 8 dB of RF Gain reduction. Or 10 dB of Attenuation and some 13 dB of RF Gain reduction. Of course the band noise will be comprised of different noise components, depending on band and many other factors as he suggests. 73 Bob, K4TAX On 9/3/2017 3:06 PM, Keith Onishi wrote: In my experience, NR is much better than NB against power line noise. However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise Eliminating Module, which is inserted between K3 line out and USB audio module. For effectively eliminating noise, tuning RF gain and AGC level in addition to NB and/or NR would give you better results. de JH3SIF, Keith 2017/09/04 4:38、Wes Stewart のメール： I agree. The adjustments are far too many and arcane. I'm currently plagued with powerline noise that has yet to be fixed, although they are supposed to be working on it. The K3S blanker is slightly better than useless. When I set it aggressive enough to be audibly useful, FT8 decodes multiple signals at 120 Hz intervals, which upsets sequencing. I'm finding that my SDR-IQ that I normally use only as a bandscope, has better noise blanking on its demodulated audio than the K3. Too bad I can't use it with WSJT-X. I suspect, but do not know for sure, (maybe the designer can enlighten us) that there is insufficient delay in the (analog) signal path and the noise gets through before blanking takes place. Wes N7WS __ Elecraft m
Re: [Elecraft] Noise Blankers
Depending the type of noise, for repetitive pulse type noise only, the Noise Blanker does it job. Now one must understand that all pulse noise is not alike. Therefore, different values of NB, both with the IF values and with DSP values, will require some adjustments. If the noise is not repetitive then the NB is not the better choice but the NR is the better choice. Again, depending on they type of noise, certain combinations of NR values will be necessary. Yes, that is correct in that the Noise Reduction function is not available or can not be activated in the DATA mode. However the Noise Blanker can be used in the DATA mode. Again, the Noise Blanker is for repetitive pulse type noise. I've spoken with many hams and find their understanding of Noise Reduction being described as often does not work as expected. Further discussion seems to indicate they want NENoise Elimination. Well, NRNoise Reduction does in fact work when the values are selected based on the type of broad noise spectrum being encountered. NR has very little effect on pulse type noise. One fact not clearly understood, is that most hams operate with too much RF Gain. Thus the correct application of ATTENUATION and RF Gain reduction will greatly improve receiver performance in the face of noise. Optimizing receiver gain compared to band noise and the noise floor of the receiver is explained in a quote from Rob Sherwood, Sherwood Engineering: "If receiver noise floor is 10 dB below band noise, the receiver is contributing less than 0.5 dB of the total noise. Band noise varies by band over 30 dB, 160-10 meters. It also varies by direction and time of day, plus what the sun is doing. In an noisy urban environment it is anybody's guess as to your band noise level. A simple test is to see how much the noise coming out your speaker increases when you switch between a dummy load and your antenna, when tuned to a dead spot on the band. Example on 10 meters at my rural QTH, IC-756 Pro III: preamp OFF, noise goes up 3 dB. That means the receiver is contributing half the noise. Preamp 1 ON, band noise goes up 9.5 dB. Almost all legacy receivers are designed for 10 meters, and attenuation is desirable on the low HF bands." In Rob's first statement, how do we get the band noise to be 10 dB above receiver noise? Use Attenuation and RF Gain reduction. As an example, if receiver noise floor is -130 dBm and the band noise, no signal, is S-5 or -97 dBm, the difference being 33 dB. This would then indicate one should employ 15 dB of Attenuation and 8 dB of RF Gain reduction. Or 10 dB of Attenuation and some 13 dB of RF Gain reduction. Of course the band noise will be comprised of different noise components, depending on band and many other factors as he suggests. 73 Bob, K4TAX On 9/3/2017 3:06 PM, Keith Onishi wrote: In my experience, NR is much better than NB against power line noise. However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise Eliminating Module, which is inserted between K3 line out and USB audio module. For effectively eliminating noise, tuning RF gain and AGC level in addition to NB and/or NR would give you better results. de JH3SIF, Keith 2017/09/04 4:38、Wes Stewart のメール： I agree. The adjustments are far too many and arcane. I'm currently plagued with powerline noise that has yet to be fixed, although they are supposed to be working on it. The K3S blanker is slightly better than useless. When I set it aggressive enough to be audibly useful, FT8 decodes multiple signals at 120 Hz intervals, which upsets sequencing. I'm finding that my SDR-IQ that I normally use only as a bandscope, has better noise blanking on its demodulated audio than the K3. Too bad I can't use it with WSJT-X. I suspect, but do not know for sure, (maybe the designer can enlighten us) that there is insufficient delay in the (analog) signal path and the noise gets through before blanking takes place. Wes N7WS On 9/3/2017 9:18 AM, K9MA wrote: I have never found the K3 noise blanker to be effective. On the other hand, in side-by-side comparisons, the noise blanker in my old FT-1000D can be very effective on my ever present power line noise. However, like all noise blankers of that design, it only works if there are no strong signals within many kHz of the operating frequency, so it's completely useless on a crowded band. The only way around this I know of is to use a second receiver, tuned to a clear spot nearby, to control the noise blanker. BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. The idea is that, in such a wide bandwidth, the amplitude of the noise pulses should be large, making them easier to distinguish from signals. (The FT-1000 uses something like 15 kHz.) However, I've never been able to get the K3 NB to work, even on a completely dead band. Under the same conditions, I can often
Re: [Elecraft] Noise Blankers
In my experience, NR is much better than NB against power line noise. However, NR does not work on DATA mode. I use BHI Compact In-line DSP Noise Eliminating Module, which is inserted between K3 line out and USB audio module. For effectively eliminating noise, tuning RF gain and AGC level in addition to NB and/or NR would give you better results. de JH3SIF, Keith > 2017/09/04 4:38、Wes Stewart のメール： > > I agree. The adjustments are far too many and arcane. I'm currently plagued > with powerline noise that has yet to be fixed, although they are supposed to > be working on it. The K3S blanker is slightly better than useless. When I set > it aggressive enough to be audibly useful, FT8 decodes multiple signals at > 120 Hz intervals, which upsets sequencing. > > I'm finding that my SDR-IQ that I normally use only as a bandscope, has > better noise blanking on its demodulated audio than the K3. Too bad I can't > use it with WSJT-X. > > I suspect, but do not know for sure, (maybe the designer can enlighten us) > that there is insufficient delay in the (analog) signal path and the noise > gets through before blanking takes place. > > Wes N7WS > > > > On 9/3/2017 9:18 AM, K9MA wrote: >> I have never found the K3 noise blanker to be effective. On the other hand, >> in side-by-side comparisons, the noise blanker in my old FT-1000D can be >> very effective on my ever present power line noise. However, like all noise >> blankers of that design, it only works if there are no strong signals within >> many kHz of the operating frequency, so it's completely useless on a crowded >> band. The only way around this I know of is to use a second receiver, tuned >> to a clear spot nearby, to control the noise blanker. >> >> BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. >> The idea is that, in such a wide bandwidth, the amplitude of the noise >> pulses should be large, making them easier to distinguish from signals. >> (The FT-1000 uses something like 15 kHz.) However, I've never been able to >> get the K3 NB to work, even on a completely dead band. Under the same >> conditions, I can often get a 20 dB reduction with the other radio. That I >> don't understand. I should investigate that sometime. >> >> 73, >> >> Scott K9MA >> >> -- >> >> Scott Ellington >> >> > > __ > 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 jh3...@sumaq.jp __ 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
Re: [Elecraft] Noise Blankers
I agree. The adjustments are far too many and arcane. I'm currently plagued with powerline noise that has yet to be fixed, although they are supposed to be working on it. The K3S blanker is slightly better than useless. When I set it aggressive enough to be audibly useful, FT8 decodes multiple signals at 120 Hz intervals, which upsets sequencing. I'm finding that my SDR-IQ that I normally use only as a bandscope, has better noise blanking on its demodulated audio than the K3. Too bad I can't use it with WSJT-X. I suspect, but do not know for sure, (maybe the designer can enlighten us) that there is insufficient delay in the (analog) signal path and the noise gets through before blanking takes place. Wes N7WS On 9/3/2017 9:18 AM, K9MA wrote: I have never found the K3 noise blanker to be effective. On the other hand, in side-by-side comparisons, the noise blanker in my old FT-1000D can be very effective on my ever present power line noise. However, like all noise blankers of that design, it only works if there are no strong signals within many kHz of the operating frequency, so it's completely useless on a crowded band. The only way around this I know of is to use a second receiver, tuned to a clear spot nearby, to control the noise blanker. BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. The idea is that, in such a wide bandwidth, the amplitude of the noise pulses should be large, making them easier to distinguish from signals. (The FT-1000 uses something like 15 kHz.) However, I've never been able to get the K3 NB to work, even on a completely dead band. Under the same conditions, I can often get a 20 dB reduction with the other radio. That I don't understand. I should investigate that sometime. 73, Scott K9MA -- Scott Ellington __ 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
Re: [Elecraft] Noise Blankers
I find the K3 NB to be surprisingly effective. I also find that adjustment is highly dependent on the characteristics of the signal and the noise, and the effects of changing those adjustments is subtle. The effect of a blanker on ignition noise was really astounding ... "was," because ignition noise seems to be history these days. I suspect that many of the "it doesn't work very well" observations may stem from anticipation of a dramatic disappearance of today's noise from incidental and unintended radiators with NB on. My local noise comes from the NV Energy power system and an uncountable number of Part 15 violators in the house and neighborhood. K3 NB is very effective for me against them. I am a bit sorry that both the IF and DSP blanker parameters are so cryptic in the K3. Depth of the blanking pulse and width of the blanking interval are the two "real" parameters involved. The K3 seems to camouflage them which, for me at least, makes them a bit harder to adjust properly, I'm not sure what I'm doing when I change them. Incidentally, punching holes in the receiver sensitivity to block noise pulses is itself introducing noise. As with everything else in life, it's a trade-off. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 9/3/2017 9:40 AM, Jim Brown wrote: On 9/3/2017 9:18 AM, K9MA wrote: I have never found the K3 noise blanker to be effective. BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. The K3 NB is really TWO blankers, operating in two different IFs. Each can be tweaked for various kinds of noise from the menu system. Access the menu by a Long Push of the NB button. It's important to understand that there are many kinds of noise. Noise blankers are most effective on IMPULSE NOISE, which is the result of something arcing, usually in the power system, but also electric fences and neon signs. Most of the residential noise we hear today is ELECTRONIC noise, generated by switch-mode power supplies and microprocessors. Noise blankers must be very different to suppress this sort of noise. The menu tweaks provided by the K3, K3S, KX3, and KX2 are very critical to making the NB effective on the noise you're experiencing. One size does NOT fit all. 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 arch...@mail-archive.com
Re: [Elecraft] Noise Blankers
On 9/3/2017 9:18 AM, K9MA wrote: I have never found the K3 noise blanker to be effective. BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. The K3 NB is really TWO blankers, operating in two different IFs. Each can be tweaked for various kinds of noise from the menu system. Access the menu by a Long Push of the NB button. It's important to understand that there are many kinds of noise. Noise blankers are most effective on IMPULSE NOISE, which is the result of something arcing, usually in the power system, but also electric fences and neon signs. Most of the residential noise we hear today is ELECTRONIC noise, generated by switch-mode power supplies and microprocessors. Noise blankers must be very different to suppress this sort of noise. The menu tweaks provided by the K3, K3S, KX3, and KX2 are very critical to making the NB effective on the noise you're experiencing. One size does NOT fit all. 73, Jim K9YC On Sep 3, 2017, at 10:37 AM, Rick Tavan wrote: Noise blankers are difficult to design and to use. They work by blanking out the receiver during noise pulses. The user defines what is a noise pulse and how aggressively to blank it by adjusting the NB parameters. __ 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
[Elecraft] Noise Blankers
I have never found the K3 noise blanker to be effective. On the other hand, in side-by-side comparisons, the noise blanker in my old FT-1000D can be very effective on my ever present power line noise. However, like all noise blankers of that design, it only works if there are no strong signals within many kHz of the operating frequency, so it's completely useless on a crowded band. The only way around this I know of is to use a second receiver, tuned to a clear spot nearby, to control the noise blanker. BTW, the K3 noise blanker uses a filter with a bandwidth of about 100 kHz. The idea is that, in such a wide bandwidth, the amplitude of the noise pulses should be large, making them easier to distinguish from signals. (The FT-1000 uses something like 15 kHz.) However, I've never been able to get the K3 NB to work, even on a completely dead band. Under the same conditions, I can often get a 20 dB reduction with the other radio. That I don't understand. I should investigate that sometime. 73, Scott K9MA -- Scott Ellington --- via iPad > On Sep 3, 2017, at 10:37 AM, Rick Tavan wrote: > > Noise blankers are difficult to design and to use. They work by blanking > out the receiver during noise pulses. The user defines what is a noise > pulse and how aggressively to blank it by adjusting the NB parameters. If > you don't blank out enough, you still hear the noise. If the signal is > below that noise, you won't hear it. If you blank out too much, you lose so > much real signal that it is no longer possible to copy or to copy > comfortably. *I have had very good results with the NB in the K3 on some > kinds of human-made noise.* Other noises seem to have too high a duty cycle > or signal strength to be effectively blanked. Your noise sources may be in > that category. I don't think it is fair to say the K3 NB "doesn't work." It > certainly does work on many kinds of noise. No NB that I have tried or > heard of can work on all kinds of noise. > > 73, > > /Rick N6XI > > > Rick Tavan > Truckee, CA > > On Sun, Sep 3, 2017 at 8:12 AM, Gian Luca Cazzola > wrote: > >> To Wayne and his Elecraft crew: >> >> I am an ultra satisfied cw user of a Elecraft K3S ( that I use with P3 and >> two SP3). >> >> The only things that I dont like are: >> - the noise blanker - i havent found situations where it help - or I am >> unable to use it, even if I tried lot of settings… >> >> - the NOISE REDUCTOR, that first times I thought it help barely, but after >> some time I found that it simply need to be reset (simple OFF-ON) at band >> noise changing time after time and it work well. >> >> About the NB I dont ask anything ( I simply accept that it doesn’t work), >> >> but about NR - Noise Reductor I ask you that with next firmware >> modifications you introduce an automatic NR reset ( at least every 5 >> minutes a ciclic OFF-ON, it simply improve a lot its results) >> >> Many thanks. >> >> 73 es gl, >> Ian IK4EWX >> __ >> 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 rta...@gmail.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 > Message delivered to k...@sdellington.us __ 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
Re: [Elecraft] Noise Blankers
Early days of TV Broadcasting we sent new projectionists to the competition to get a box of sprocket holes - they always came back with them! But when we sent them for a camera cable stretcher (does exist) they wouldn't go. George AI4VZ Hi all, > >All of which don't exist. > And in the aircraft mechanic trade we sent them out to get a bucket of > prop wash ;o) And in the electronics trade (tube days) we sent them out to get a drip pan for grid leak resistors. __ 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] Noise Blankers
On Fri, 08 Jan 2010 08:23:01 -0500, Mike wrote: [snip] >> >Y'all didn't use flight line to tie that bucket under the nacelle? > >73, Mike NF4L Yes, but we did that before the prop wash trick. When we sent them for prop wash we sent them to the flight line, the location of which they now knew. And when I worked on the Harris 4 color press at Gulf Printing in Houston, we would send the new guys upstairs to meet our stripper. Great fun ;o) Tom, N5GE __ 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] Noise Blankers
I worked in a TV factory, 1968. We sent the new guys to the supply window for a raster stretcher. Steve N4LQ n...@carolina.rr.com - Original Message - From: To: Sent: Friday, January 08, 2010 1:06 AM Subject: Re: [Elecraft] Noise Blankers > Hi all, > >> >All of which don't exist. > >> And in the aircraft mechanic trade we sent them out to get a bucket of >> prop wash ;o) > > And in the electronics trade (tube days) we sent them out to get a drip > pan for grid > leak resistors. > > 73, > > George T Daughters, K6GT > CU in the California QSO Party (CQP) > October 2-3, 2010 > > > __ > 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 No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.725 / Virus Database: 270.14.129/2606 - Release Date: 01/07/10 14:35:00 __ 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] Noise Blankers
Radio Amateur N5GE wrote: > On Thu, 7 Jan 2010 11:34:50 -0800 (PST), Wes Stewart > wrote: > > >> One of the tricks pulled on new >> guys was a customer or another salesman asking for a set of spark plugs >> for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a >> Powerglide transmission. >> >> All of which don't exist. >> >> Wes N7WS >> >> > > And in the aircraft mechanic trade we sent them out to get a bucket of > prop wash ;o) > Y'all didn't use flight line to tie that bucket under the nacelle? 73, Mike NF4L __ 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] Noise Blankers
Hi all, > >All of which don't exist. > And in the aircraft mechanic trade we sent them out to get a bucket of > prop wash ;o) And in the electronics trade (tube days) we sent them out to get a drip pan for grid leak resistors. 73, George T Daughters, K6GT CU in the California QSO Party (CQP) October 2-3, 2010 __ 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] Noise Blankers
On Thu, 7 Jan 2010 11:34:50 -0800 (PST), Wes Stewart wrote: >One of the tricks pulled on new >guys was a customer or another salesman asking for a set of spark plugs >for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a >Powerglide transmission. > >All of which don't exist. > >Wes N7WS > And in the aircraft mechanic trade we sent them out to get a bucket of prop wash ;o) Tom, N5GE n...@n5ge.com K3 #806 with SUB RX, K3 #1055, PR6, XV144, XV432, KRC2, W1, 2 W2's and other small kits 1 K144XV on order http://www.n5ge.com http://www.swotrc.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
Re: [Elecraft] Noise Blankers
--- On Thu, 1/7/10, Guy Olinger K2AV wrote: > A six cylinder diesel doesn't have > ignition noise. Actually, some old International Harvester diesels did have spark plugs. They started on gasoline and after they warmed up, the operator switched them over to diesel :-) Otherwise, this reminds me of a story. When I was a teenager, my dad, who managed a large automotive machine shop associated with an automotive and industrial parts store, got me a summer job there as a parts guy. One of the tricks pulled on new guys was a customer or another salesman asking for a set of spark plugs for a Cummins, a radiator cap for a Corvair or an oil pan gasket for a Powerglide transmission. All of which don't exist. Wes N7WS __ 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] Noise Blankers
On Thu, 7 Jan 2010 12:47:52 -0500, Guy Olinger K2AV wrote: >A six cylinder diesel doesn't have ignition noise. What noise are you >comparing against? 73, Guy. > >> Having said that, I have a 6 cylinder diesel that does give my TS-480SAT >> some measure of grief. [snip] Guy and all, If the diesel has electronically timed injectors, the injector timing circuitry could be causing noise. Tom, N5GE n...@n5ge.com K3 #806 with SUB RX, K3 #1055, PR6, XV144, XV432, KRC2, W1, 2 W2's and other small kits 1 K144XV on order http://www.n5ge.com http://www.swotrc.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
Re: [Elecraft] Noise Blankers
A diesel fuel injection pump/system makes all kinds of electrical noise. There is no electrical ignition system in a diesel engine. 73, matt, W6NIA On Thu, 07 Jan 2010 12:47:52 -0500, you wrote: >A six cylinder diesel doesn't have ignition noise. What noise are you >comparing against? 73, Guy. > >On Wed, Jan 6, 2010 at 11:38 PM, wrote: >> To be honest I have not found any noise the NB would not get rid of. >> >> Having said that, I have a 6 cylinder diesel that does give my TS-480SAT >> some measure of grief. >> >> Just for my own knowledge I hooked the K3 to the same power lead fitted with >> Anderson plugs as with all my power leads, and, the result was impressive. >> >> Where the 480 was struggling the K3 shone and I was happy with the result. >> >> >From this you can surmise that the K3 NB is very effective on ignition >> >noise. >> >> Hope you are getting good information to help you decide. >> >> 73's and good luck whichever way you jump. >> >> Gary >> VK4FD >> Sent via BlackBerry® from Telstra >> __ >> 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] Noise Blankers
A six cylinder diesel doesn't have ignition noise. What noise are you comparing against? 73, Guy. On Wed, Jan 6, 2010 at 11:38 PM, wrote: > To be honest I have not found any noise the NB would not get rid of. > > Having said that, I have a 6 cylinder diesel that does give my TS-480SAT some > measure of grief. > > Just for my own knowledge I hooked the K3 to the same power lead fitted with > Anderson plugs as with all my power leads, and, the result was impressive. > > Where the 480 was struggling the K3 shone and I was happy with the result. > > >From this you can surmise that the K3 NB is very effective on ignition noise. > > Hope you are getting good information to help you decide. > > 73's and good luck whichever way you jump. > > Gary > VK4FD > Sent via BlackBerry® from Telstra > __ > 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] Noise Blankers
Hello Tom, I am plagued by excessive amounts of power line noise on 50, 144 and 222MHz. It has been going on for years to the point where the FCC (both Riley Hollingsworth and Laura Smith) have sent letters to the local utility. I have used several receivers and none really took out the noise as effectively as the K3 has. I find that for my situation, the DSP blanker is quite good when things get bad. In the past I have seen other noise blankers get swamped out by so many noise pulses that they have lost effectiveness. Simple noises of maybe one or two arcing points can be removed, but 7 or 8 is another story. As more noise comes on, the blankers fare more poorly. (Yes, one power pole can have 7 or 8 points that are generating rfi) With the K3, I have been able to negate most of the noise and still am able to operate through the noise by adjusting the DSP NR settings along with IF blanking. I find that the DSP NR works better for my situation. My antennas are high and in the clear. The worst noise problem has come from a 34.5 KV line that is seven miles from my antenna. It is typically peaking S7 and is composed of many arcing tie wires and leaking insulators. Only the K3 has removed this noise as a factor in receiving. My other radios with only IF blanking do absolutely nothing to the noise in that direction. The nice thing is that you can tailor the effect on the fly and immediately tell which setting works best. I am pleased with the DSP as it does not overload with strong signals. While it makes the audio sound somewhat ugly at aggressive settings, the overall outcome is positive. I am more than happy with the noise performance of the K3. It is quite a tool. I believe the Flex Radio is another stellar performer in this area, but I have not tried it at my QTH. Dave K1WHS - Original Message - From: "Tom Bickley" To: Sent: Thursday, January 07, 2010 1:38 AM Subject: [Elecraft] Noise Blankers > > I'm overdue for a new radio (at least, that's what I am telling my > XYL). In considering the purchase, unfortunately one of the major > considerations I must take into account is > the noise blanker function. I have recently moved to an area with A LOT > of power line noise. I have high voltage lines around my immediate QTH. > It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on > really > cold mornings, a seperate, additional noise kicks in that takes it to > S9 or more. I am trying to locate these noise sources but have been > unable to so far. I must run the noise blanker on my old TS-850s at all > times to help me manage this problem. With the NB engaged (which > is 'always') I have audio distortion created from nearby signals, > especially stronger signals within 30 > kc's of my receive frequency, no matter at what level I run either of the > noise > blankers. > > I would like to hear from K3 owners who might have > 'line noise problems' and know how the noise blanker in your K3 handles > the problem. > > Mni Tnx / 73 > K4NA > > _ > Hotmail: Powerful Free email with security by Microsoft. > http://clk.atdmt.com/GBL/go/196390710/direct/01/ > __ > 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] Noise Blankers
Tom, I find the noise blanker on the K3 to be extremely good. I have been plagued with power line noise for years at my QTH, and the K3 is the first rig I've owned that can knock it out. It takes a bit of tweaking, and for reasons I don't understand the power line noise on Tuesday night might require a different setting than the power line noise on Monday night. During the Geminids meteor shower last month I had some strange impulse noise that would have wiped me out with my previous rigs. With the K3's noise blanker I was able to carefully remove it without destroying the weak-signal capability and worked a pile of stations on 6m meteor scatter. Try one out--you'll love it! 73 Eric WD6DBM __ 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] Noise Blankers
To be honest I have not found any noise the NB would not get rid of. Having said that, I have a 6 cylinder diesel that does give my TS-480SAT some measure of grief. Just for my own knowledge I hooked the K3 to the same power lead fitted with Anderson plugs as with all my power leads, and, the result was impressive. Where the 480 was struggling the K3 shone and I was happy with the result. >From this you can surmise that the K3 NB is very effective on ignition noise. Hope you are getting good information to help you decide. 73's and good luck whichever way you jump. Gary VK4FD Sent via BlackBerry® from Telstra __ 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] Noise Blankers
Tom, I'm a new K3 owner, coming from an ICOM PRO II, and still learning how to use the K3. I live with a pretty constant S9 or better noise level. I think most of it is power line. Whatever it is, the NB on the K3 knocks the cover off the ICOM. 73, Mike NF4L Tom Bickley wrote: > I'm overdue for a new radio (at least, that's what I am telling my > XYL). In considering the purchase, unfortunately one of the major > considerations I must take into account is > the noise blanker function. I have recently moved to an area with A LOT > of power line noise. I have high voltage lines around my immediate QTH. > It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on > really > cold mornings, a seperate, additional noise kicks in that takes it to > S9 or more. I am trying to locate these noise sources but have been > unable to so far. I must run the noise blanker on my old TS-850s at all times > to help me manage this problem. With the NB engaged (which > is 'always') I have audio distortion created from nearby signals, > especially stronger signals within 30 > kc's of my receive frequency, no matter at what level I run either of the > noise > blankers. > > I would like to hear from K3 owners who might have > 'line noise problems' and know how the noise blanker in your K3 handles > the problem. > > Mni Tnx / 73 > K4NA > > _ > Hotmail: Powerful Free email with security by Microsoft. > http://clk.atdmt.com/GBL/go/196390710/direct/01/ > __ > 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] Noise Blankers
Hi Tom, Well, I have a K3 noise blanker story for you. About two months ago, I suddenly had an S9+20 line noise problem around here. I knew it was some type of failed Edison equipment, or maybe something at a residence. It was loud enough to hear with a stubby for ANT1, and on 80m through 30m under any conditions. I had to diddle the K3's noise blanker a bit to get it dialed in right, but I finally killed the crud on the Main and Sub receivers. There was a residual amount of distortion; I had never run the NB this aggressively before - never had to. However, effectively the noise was blanked down to S7 or so on 40m where it was the worst. And it made 80m usable again on CW... In a few days, an Edison power quality tech came out and located the noise source. Some customer-owned (but unused) transformers on a citrus farm a few blocks from us had open primaries. He had the feed to them disconnected and notified the owner that they needed to be replaced (they weren't working anyway). These transformers were used to power irrigation pumps, so the owner got the problem cleared up right away. I was completely amazed how well the NB works under very difficult conditions. May no one else have to find out how well this feature works in the same way or for a similar reason. 73, matt W6NIA K3 #24 K2 #2810 Except for being a paying customer, I have no formal affiliation with Elecraft. On Thu, 07 Jan 2010 01:38:35 +, you wrote: > >I'm overdue for a new radio (at least, that's what I am telling my >XYL). In considering the purchase, unfortunately one of the major >considerations I must take into account is >the noise blanker function. I have recently moved to an area with A LOT >of power line noise. I have high voltage lines around my immediate QTH. >It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on >really >cold mornings, a seperate, additional noise kicks in that takes it to >S9 or more. I am trying to locate these noise sources but have been >unable to so far. I must run the noise blanker on my old TS-850s at all times >to help me manage this problem. With the NB engaged (which >is 'always') I have audio distortion created from nearby signals, >especially stronger signals within 30 >kc's of my receive frequency, no matter at what level I run either of the noise >blankers. > >I would like to hear from K3 owners who might have >'line noise problems' and know how the noise blanker in your K3 handles >the problem. > >Mni Tnx / 73 > K4NA > >_ >Hotmail: Powerful Free email with security by Microsoft. >http://clk.atdmt.com/GBL/go/196390710/direct/01/ >__ >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] Noise Blankers
The K3 blankers have a considerable range of adjustability of both the blanking threshold with seven steps, and the blanking pulse width with three steps, with independent settings for hardware blanking and dsp blanking. Hopefully, you can find a setting that will work without excess distortion but that may not always be the case if the noise is relatively low and the inband signals are not. There is a learning curve. Blanker effectiveness was one of my criteria for selecting the K3. 73, Dunc, W5DC Tom Bickley wrote: > I'm overdue for a new radio (at least, that's what I am telling my > XYL). In considering the purchase, unfortunately one of the major > considerations I must take into account is > the noise blanker function. I have recently moved to an area with A LOT > of power line noise. I have high voltage lines around my immediate QTH. > It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on > really > cold mornings, a seperate, additional noise kicks in that takes it to > S9 or more. I am trying to locate these noise sources but have been > unable to so far. I must run the noise blanker on my old TS-850s at all times > to help me manage this problem. With the NB engaged (which > is 'always') I have audio distortion created from nearby signals, > especially stronger signals within 30 > kc's of my receive frequency, no matter at what level I run either of the > noise > blankers. > > I would like to hear from K3 owners who might have > 'line noise problems' and know how the noise blanker in your K3 handles > the problem. > > Mni Tnx / 73 > K4NA > > _ > Hotmail: Powerful Free email with security by Microsoft. > http://clk.atdmt.com/GBL/go/196390710/direct/01/ > __ > 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] Noise Blankers
Hi Tom, You'll get a lot of opinions on noise blankers, I suspect :) Here's my 2 cents: The K3's combination of two noise blankers -- one at the 1st IF and one at the DSP -- can work wonders on all sorts of noise. But it's especially good with power-line noise (loads of that at my QTH). The K3 doesn't pre-filter down to 15 kHz, which means the sharp pulse rise-times are preseved. This means you can typically keep the IF blanker's threshold very high, minimizing the type of IMD that all IF blankers cause. The DSP blanker is icing on the cake, especially if you also have complex noise like that from switching supplies, etc. (stuff that drifts a lot). That said, I suggest you borrow a K3 and try it at your QTH. We can find a nearby K3 owner for you, or you can ask on the reflector. Good luck with whatever rig you choose, and don't hesitate to post further questions. 73, Wayne N6KR On Jan 6, 2010, at 5:38 PM, Tom Bickley wrote: > > I'm overdue for a new radio (at least, that's what I am telling my > XYL). In considering the purchase, unfortunately one of the major > considerations I must take into account is > the noise blanker function. I have recently moved to an area with A > LOT > of power line noise. I have high voltage lines around my immediate > QTH. > It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on > really > cold mornings, a seperate, additional noise kicks in that takes it to > S9 or more. I am trying to locate these noise sources but have been > unable to so far. I must run the noise blanker on my old TS-850s at > all times to help me manage this problem. With the NB engaged (which > is 'always') I have audio distortion created from nearby signals, > especially stronger signals within 30 > kc's of my receive frequency, no matter at what level I run either > of the noise > blankers. > > I would like to hear from K3 owners who might have > 'line noise problems' and know how the noise blanker in your K3 > handles > the problem. > > Mni Tnx / 73 > K4NA > > _ > Hotmail: Powerful Free email with security by Microsoft. > http://clk.atdmt.com/GBL/go/196390710/direct/01/ > __ > 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] Noise Blankers
I'm overdue for a new radio (at least, that's what I am telling my XYL). In considering the purchase, unfortunately one of the major considerations I must take into account is the noise blanker function. I have recently moved to an area with A LOT of power line noise. I have high voltage lines around my immediate QTH. It is a constant S3 to S5 on all bands above 7 MHz and, sometimes on really cold mornings, a seperate, additional noise kicks in that takes it to S9 or more. I am trying to locate these noise sources but have been unable to so far. I must run the noise blanker on my old TS-850s at all times to help me manage this problem. With the NB engaged (which is 'always') I have audio distortion created from nearby signals, especially stronger signals within 30 kc's of my receive frequency, no matter at what level I run either of the noise blankers. I would like to hear from K3 owners who might have 'line noise problems' and know how the noise blanker in your K3 handles the problem. Mni Tnx / 73 > K4NA _ Hotmail: Powerful Free email with security by Microsoft. http://clk.atdmt.com/GBL/go/196390710/direct/01/ __ 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
