Re: [Elecraft] K3 Questions and gripes
Second what Joe said... On Tue, Dec 14, 2010 at 12:27 PM, Joe Subich, W4TV wrote: > > > If you have the 6-kHz filter installed, you can increase the > > effectiveness of the DSP NB with some kinds of noise in SSB mode; just > > set WIDTH above 2.8 kHz so this wider filter will be selected. > > Or modify your configuration so the wider roofing filter is always > selected in SSB . > > Wayne, this is a place the XFIL button could be made more useful ... > allow it to select the roofing filter independent of the "Width" > (DSP) setting. > > 73, > > ... Joe, W4TV > > > On 12/14/2010 12:12 PM, Wayne Burdick wrote: >> Scott, >> >> On Dec 14, 2010, at 8:28 AM, Scott Ellington wrote: >> >>> The K3 noise blanker bandpass filter appears to have a bandwidth of >>> about 400 kHz >> >>> I'm just guessing, but it seems Elecraft took a different approach >>> in using the very wide bandwidth. This increases the peak amplitude >>> of the noise pulses, allowing them to be detected at a higher >>> threshold while, under crowded band conditions, the strongest signal >>> remains about the same >> >> Exactly. >> >> If you need a narrow-band blanker, use the DSP NB. It is very >> effective on a wide range of noise types, and is post-crystal filter. >> >> If you have the 6-kHz filter installed, you can increase the >> effectiveness of the DSP NB with some kinds of noise in SSB mode; just >> set WIDTH above 2.8 kHz so this wider filter will be selected. >> >> Wayne >> >> __ >> 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 Questions and gripes
> If you have the 6-kHz filter installed, you can increase the > effectiveness of the DSP NB with some kinds of noise in SSB mode; just > set WIDTH above 2.8 kHz so this wider filter will be selected. Or modify your configuration so the wider roofing filter is always selected in SSB . Wayne, this is a place the XFIL button could be made more useful ... allow it to select the roofing filter independent of the "Width" (DSP) setting. 73, ... Joe, W4TV On 12/14/2010 12:12 PM, Wayne Burdick wrote: > Scott, > > On Dec 14, 2010, at 8:28 AM, Scott Ellington wrote: > >> The K3 noise blanker bandpass filter appears to have a bandwidth of >> about 400 kHz > >> I'm just guessing, but it seems Elecraft took a different approach >> in using the very wide bandwidth. This increases the peak amplitude >> of the noise pulses, allowing them to be detected at a higher >> threshold while, under crowded band conditions, the strongest signal >> remains about the same > > Exactly. > > If you need a narrow-band blanker, use the DSP NB. It is very > effective on a wide range of noise types, and is post-crystal filter. > > If you have the 6-kHz filter installed, you can increase the > effectiveness of the DSP NB with some kinds of noise in SSB mode; just > set WIDTH above 2.8 kHz so this wider filter will be selected. > > Wayne > > __ > 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 Questions and gripes
Your "In the absence of strong signals" caveat is a big one. The entirely DSP key-click nullification works. I would think that if a pulse is detected, and the wave shape of the pulse artifact after filtering is known, that the known shape can be used in some digital fashion to remove it. Or to get away from the analog detect-and-then-remove modus, if the pulse artifact is detected, simply remove it, no pre-notification required. I have a pole around here somewhere that goes bad from time to time, and the pulses are extremely narrow and spikey. The IF method narrow 3 or 4 gets them nicely --- except when there is a contest and a band full of very loud signals, in which case the ancient analog noise-blank artifacts are there too, making it unusable. The DSP method is not as clean as the IF on a quiet band, but it does usable good in a contest. 73, Guy. On Tue, Dec 14, 2010 at 12:48 PM, Scott Ellington wrote: > My comments apply to ONLY the IF (hardware) noise blanker. Sorry I didn't > make that clear, but I'm a hardware guy. > > The reason for having the IF NB is that short-duration noise pulses, like the > ubiquitous power line noise, must be detected ahead of narrow bandpass > filters, which effectively lengthen the pulses. This allows the noise gate > to switch off during the short noise pulse, with minimal effect on the > desired signals. I don't believe any kind of DSP cleverness, applied after > the IF crystal filter, can be as effective for this kind of noise. In the > absence of strong signals, as I'm sure many others have found, these noise > blankers can be very effective indeed. > > 73, > > Scott K9MA > > > On Dec 14, 2010, at 11:28 AM, Guy Olinger K2AV wrote: > >> The K3 has a dual methodology. 1) DSP and 2) traditional analog IF >> pulse detection noise blanking which shuts off the IF for very short >> intervals around the pulse. >> >> Doesn't your commentary only apply to the IF NB methods of the K3? >> The DSP methods take place in firmware, analyzing and adjusting the >> number stream to "remove" noise. The very successful key click >> suppression only works with the IF method off, and using the DSP >> method T2-7 and T3-7. >> >> I agree with your analysis as long as it is qualified to the K3 NB's >> IF method. Your reasoning below also pertains to why the IF method >> needs to be off for key click suppression. Digital NB artifacts are >> not related to the after-effects of analog IF noise blanking. >> >> I was at first surprised that the analog IF blanking was retained in >> the K3. But over time there have been many posts about successful use >> of the IF blanking and IF/DSP combinations, validating Elecraft's >> retention, however ancient the issues and artifacts of the IF method >> may be. >> >> 73, Guy. >> >> On Tue, Dec 14, 2010 at 11:28 AM, Scott Ellington >> wrote: >>> The K3 noise blanker bandpass filter appears to have a bandwidth of about >>> 400 kHz, so any strong signal within that bandwidth will affect its >>> operation. This is a problem with all noise blankers of this type, as >>> they can't detect noise pulses smaller than the strongest signal within the >>> filter bandwidth. Some use a narrower filter, perhaps 15 kHz, to minimize >>> the chance a strong signal is in its passband. That, of course, us usually >>> still far too wide during a contest, and the noise blanker just won't work >>> with a narrower bandwidth. One solution is the "Evasive Noise Blanker", >>> which essentially uses a second receiver to detect noise pulses at a >>> slightly different frequency, for example, just outside the ham band. I >>> may someday investigate trying to do that with the K3. >>> >>> I'm just guessing, but it seems Elecraft took a different approach in using >>> the very wide bandwidth. This increases the peak amplitude of the noise >>> pulses, allowing them to be detected at a higher threshold while, under >>> crowded band conditions, the strongest signal remains about the same. >>> >>> By the way, many have noticed, I'm sure, that noise blankers are at times >>> much more effective than at others, even if the characteristics of the >>> noise are the same. Generally, they work great when there are no strong >>> signals around. When there are strong signals in the NB filter passband, >>> the noise detection threshold goes up as a result of NB AGC action, and the >>> same noise pulses may not be detected at all. That can happen even when >>> the obvious distortion from the NB isn't present. >>> >>> 73, >>> >>> Scott K9MA >>> >>> >>> On Dec 12, 2010, at 9:59 AM, David F. Reed wrote: >>> Hi folks; Yes, I really love my K3 in spite of my questions and gripes; here they are: 1. During the 10 meter contest, I was up around 28.400 operating SSB with the NB on, when I noticed that I was getting a strong CW signal pumping my AGC (or so it seemed). In doing a little researc
Re: [Elecraft] K3 Questions and gripes
My comments apply to ONLY the IF (hardware) noise blanker. Sorry I didn't make that clear, but I'm a hardware guy. The reason for having the IF NB is that short-duration noise pulses, like the ubiquitous power line noise, must be detected ahead of narrow bandpass filters, which effectively lengthen the pulses. This allows the noise gate to switch off during the short noise pulse, with minimal effect on the desired signals. I don't believe any kind of DSP cleverness, applied after the IF crystal filter, can be as effective for this kind of noise. In the absence of strong signals, as I'm sure many others have found, these noise blankers can be very effective indeed. 73, Scott K9MA On Dec 14, 2010, at 11:28 AM, Guy Olinger K2AV wrote: > The K3 has a dual methodology. 1) DSP and 2) traditional analog IF > pulse detection noise blanking which shuts off the IF for very short > intervals around the pulse. > > Doesn't your commentary only apply to the IF NB methods of the K3? > The DSP methods take place in firmware, analyzing and adjusting the > number stream to "remove" noise. The very successful key click > suppression only works with the IF method off, and using the DSP > method T2-7 and T3-7. > > I agree with your analysis as long as it is qualified to the K3 NB's > IF method. Your reasoning below also pertains to why the IF method > needs to be off for key click suppression. Digital NB artifacts are > not related to the after-effects of analog IF noise blanking. > > I was at first surprised that the analog IF blanking was retained in > the K3. But over time there have been many posts about successful use > of the IF blanking and IF/DSP combinations, validating Elecraft's > retention, however ancient the issues and artifacts of the IF method > may be. > > 73, Guy. > > On Tue, Dec 14, 2010 at 11:28 AM, Scott Ellington > wrote: >> The K3 noise blanker bandpass filter appears to have a bandwidth of about >> 400 kHz, so any strong signal within that bandwidth will affect its >> operation. This is a problem with all noise blankers of this type, as they >> can't detect noise pulses smaller than the strongest signal within the >> filter bandwidth. Some use a narrower filter, perhaps 15 kHz, to minimize >> the chance a strong signal is in its passband. That, of course, us usually >> still far too wide during a contest, and the noise blanker just won't work >> with a narrower bandwidth. One solution is the "Evasive Noise Blanker", >> which essentially uses a second receiver to detect noise pulses at a >> slightly different frequency, for example, just outside the ham band. I may >> someday investigate trying to do that with the K3. >> >> I'm just guessing, but it seems Elecraft took a different approach in using >> the very wide bandwidth. This increases the peak amplitude of the noise >> pulses, allowing them to be detected at a higher threshold while, under >> crowded band conditions, the strongest signal remains about the same. >> >> By the way, many have noticed, I'm sure, that noise blankers are at times >> much more effective than at others, even if the characteristics of the noise >> are the same. Generally, they work great when there are no strong signals >> around. When there are strong signals in the NB filter passband, the noise >> detection threshold goes up as a result of NB AGC action, and the same noise >> pulses may not be detected at all. That can happen even when the obvious >> distortion from the NB isn't present. >> >> 73, >> >> Scott K9MA >> >> >> On Dec 12, 2010, at 9:59 AM, David F. Reed wrote: >> >>> Hi folks; >>> >>> Yes, I really love my K3 in spite of my questions and gripes; here they are: >>> >>> 1. During the 10 meter contest, I was up around 28.400 operating SSB >>> with the NB on, when I noticed that I was getting a strong CW >>> signal pumping my AGC (or so it seemed). >>> >>> In doing a little research, I found the cw station responsible was >>> down at 28.023, at about S9+40 db; by call, I know the station and >>> that he is about 3 miles away. Far enough and weak enough that I >>> should not be receiving this sort of interference I think, given >>> there are no key clicks, etc. >>> >>> I turn off the NB, and it clears up completely, even 500Hz away, >>> let alone 300 or 400 KHz away. I go back up, no problem except I >>> want to use the NB; turn it back on, problem re-appears. >>> >>> This seems to be an artifact of how the NB is implemented, >>> rendering it useless under these sorts of circumstances. >>> >>> Am I missing something, out of adjustment, or ??? >>> >>> 2. The power switch - early serial number (1476); my power switch - >>> well the rubber / plastic part you press on - is starting to look >>> like a mouse has nibbled on it, with little divots falling off >>> along the top and right side edges. It is looking qu
Re: [Elecraft] K3 Questions and gripes
The K3 has a dual methodology. 1) DSP and 2) traditional analog IF pulse detection noise blanking which shuts off the IF for very short intervals around the pulse. Doesn't your commentary only apply to the IF NB methods of the K3? The DSP methods take place in firmware, analyzing and adjusting the number stream to "remove" noise. The very successful key click suppression only works with the IF method off, and using the DSP method T2-7 and T3-7. I agree with your analysis as long as it is qualified to the K3 NB's IF method. Your reasoning below also pertains to why the IF method needs to be off for key click suppression. Digital NB artifacts are not related to the after-effects of analog IF noise blanking. I was at first surprised that the analog IF blanking was retained in the K3. But over time there have been many posts about successful use of the IF blanking and IF/DSP combinations, validating Elecraft's retention, however ancient the issues and artifacts of the IF method may be. 73, Guy. On Tue, Dec 14, 2010 at 11:28 AM, Scott Ellington wrote: > The K3 noise blanker bandpass filter appears to have a bandwidth of about 400 > kHz, so any strong signal within that bandwidth will affect its operation. > This is a problem with all noise blankers of this type, as they can't detect > noise pulses smaller than the strongest signal within the filter bandwidth. > Some use a narrower filter, perhaps 15 kHz, to minimize the chance a strong > signal is in its passband. That, of course, us usually still far too wide > during a contest, and the noise blanker just won't work with a narrower > bandwidth. One solution is the "Evasive Noise Blanker", which essentially > uses a second receiver to detect noise pulses at a slightly different > frequency, for example, just outside the ham band. I may someday investigate > trying to do that with the K3. > > I'm just guessing, but it seems Elecraft took a different approach in using > the very wide bandwidth. This increases the peak amplitude of the noise > pulses, allowing them to be detected at a higher threshold while, under > crowded band conditions, the strongest signal remains about the same. > > By the way, many have noticed, I'm sure, that noise blankers are at times > much more effective than at others, even if the characteristics of the noise > are the same. Generally, they work great when there are no strong signals > around. When there are strong signals in the NB filter passband, the noise > detection threshold goes up as a result of NB AGC action, and the same noise > pulses may not be detected at all. That can happen even when the obvious > distortion from the NB isn't present. > > 73, > > Scott K9MA > > > On Dec 12, 2010, at 9:59 AM, David F. Reed wrote: > >> Hi folks; >> >> Yes, I really love my K3 in spite of my questions and gripes; here they are: >> >> 1. During the 10 meter contest, I was up around 28.400 operating SSB >> with the NB on, when I noticed that I was getting a strong CW >> signal pumping my AGC (or so it seemed). >> >> In doing a little research, I found the cw station responsible was >> down at 28.023, at about S9+40 db; by call, I know the station and >> that he is about 3 miles away. Far enough and weak enough that I >> should not be receiving this sort of interference I think, given >> there are no key clicks, etc. >> >> I turn off the NB, and it clears up completely, even 500Hz away, >> let alone 300 or 400 KHz away. I go back up, no problem except I >> want to use the NB; turn it back on, problem re-appears. >> >> This seems to be an artifact of how the NB is implemented, >> rendering it useless under these sorts of circumstances. >> >> Am I missing something, out of adjustment, or ??? >> >> 2. The power switch - early serial number (1476); my power switch - >> well the rubber / plastic part you press on - is starting to look >> like a mouse has nibbled on it, with little divots falling off >> along the top and right side edges. It is looking quite ragged. >> Has anyone else had this, or know if I can replace just the >> rubber/plastic part, or do I need to replace the entire switch >> assembly? >> >> Thanks and 73 de Dave, W5SV >> __ >> > > Scott Ellington > Madison, Wisconsin > USA > > > > __ > 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
Re: [Elecraft] K3 Questions and gripes
Scott, On Dec 14, 2010, at 8:28 AM, Scott Ellington wrote: > The K3 noise blanker bandpass filter appears to have a bandwidth of > about 400 kHz > I'm just guessing, but it seems Elecraft took a different approach > in using the very wide bandwidth. This increases the peak amplitude > of the noise pulses, allowing them to be detected at a higher > threshold while, under crowded band conditions, the strongest signal > remains about the same Exactly. If you need a narrow-band blanker, use the DSP NB. It is very effective on a wide range of noise types, and is post-crystal filter. If you have the 6-kHz filter installed, you can increase the effectiveness of the DSP NB with some kinds of noise in SSB mode; just set WIDTH above 2.8 kHz so this wider filter will be selected. Wayne __ 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 Questions and gripes
The K3 noise blanker bandpass filter appears to have a bandwidth of about 400 kHz, so any strong signal within that bandwidth will affect its operation. This is a problem with all noise blankers of this type, as they can't detect noise pulses smaller than the strongest signal within the filter bandwidth. Some use a narrower filter, perhaps 15 kHz, to minimize the chance a strong signal is in its passband. That, of course, us usually still far too wide during a contest, and the noise blanker just won't work with a narrower bandwidth. One solution is the "Evasive Noise Blanker", which essentially uses a second receiver to detect noise pulses at a slightly different frequency, for example, just outside the ham band. I may someday investigate trying to do that with the K3. I'm just guessing, but it seems Elecraft took a different approach in using the very wide bandwidth. This increases the peak amplitude of the noise pulses, allowing them to be detected at a higher threshold while, under crowded band conditions, the strongest signal remains about the same. By the way, many have noticed, I'm sure, that noise blankers are at times much more effective than at others, even if the characteristics of the noise are the same. Generally, they work great when there are no strong signals around. When there are strong signals in the NB filter passband, the noise detection threshold goes up as a result of NB AGC action, and the same noise pulses may not be detected at all. That can happen even when the obvious distortion from the NB isn't present. 73, Scott K9MA On Dec 12, 2010, at 9:59 AM, David F. Reed wrote: > Hi folks; > > Yes, I really love my K3 in spite of my questions and gripes; here they are: > > 1. During the 10 meter contest, I was up around 28.400 operating SSB > with the NB on, when I noticed that I was getting a strong CW > signal pumping my AGC (or so it seemed). > > In doing a little research, I found the cw station responsible was > down at 28.023, at about S9+40 db; by call, I know the station and > that he is about 3 miles away. Far enough and weak enough that I > should not be receiving this sort of interference I think, given > there are no key clicks, etc. > > I turn off the NB, and it clears up completely, even 500Hz away, > let alone 300 or 400 KHz away. I go back up, no problem except I > want to use the NB; turn it back on, problem re-appears. > > This seems to be an artifact of how the NB is implemented, > rendering it useless under these sorts of circumstances. > > Am I missing something, out of adjustment, or ??? > > 2. The power switch - early serial number (1476); my power switch - > well the rubber / plastic part you press on - is starting to look > like a mouse has nibbled on it, with little divots falling off > along the top and right side edges. It is looking quite ragged. > Has anyone else had this, or know if I can replace just the > rubber/plastic part, or do I need to replace the entire switch > assembly? > > Thanks and 73 de Dave, W5SV > __ > Scott Ellington Madison, Wisconsin USA __ 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 Questions and gripes
Hardy, Known issue with some runs of the small knobs. Contact k3supp...@elecraft.com and they'll get you replacements. 73, ... Joe, W4TV On 12/12/2010 12:02 PM, Hardy Landskov wrote: > Hi All, > I just had my first failure on the K3. I noticed both the AF& RF small > knobs were slipping so I thought the set screws were loose. But closer > examination showed that both knobs were cracked. I replaced them with some > small aluminum ones from Radio Shack. I don't think I over tightened the > knobs when I built the radio. > Is this a problem with other radios? Maybe I got a bad pair. > 73 Hardy N7RT > > - Original Message - > From: "David F. Reed" > To: "elecraft Reflector"; > > Sent: Sunday, December 12, 2010 8:59 AM > Subject: [Elecraft] K3 Questions and gripes > > >> Hi folks; >> >>2. The power switch - early serial number (1476); my power switch - >> well the rubber / plastic part you press on - is starting to look >> like a mouse has nibbled on it, with little divots falling off >> along the top and right side edges. It is looking quite ragged. >> Has anyone else had this, or know if I can replace just the >> rubber/plastic part, or do I need to replace the entire switch >> assembly? >> >> Thanks and 73 de Dave, W5SV >> __ >> 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 Questions and gripes
If you look at the K3 schematic you can see that the noise blanker takeoff point is at the output of the first post mixer amplifier. The bandwidth here is necessarily wide. In the blanker itself, there is a double-tuned bandpass filter at the input of the noise amplifier(s). I don't know what the bandwidth of this is, but to minimize the effects on the risetime of noise pulses, it should be as broad as possible. There are then a couple of opportunities for mischief. 1) Strong signals get into the noise amplifier and overdrive the first stage 2) Any signal getting into the noise amplifier that is strong enough to exceed the blanking threshold looks like noise and generates blanking pulses. That is simply the nature of the beast. Wes N7WS --- On Sun, 12/12/10, David F. Reed wrote: > Hi folks; > > Yes, I really love my K3 in spite of my questions and > gripes; here they are: > > 1. During the 10 meter contest, I was up > around 28.400 operating SSB > with the NB on, when I noticed that I > was getting a strong CW > signal pumping my AGC (or so it > seemed). > > In doing a little research, I found > the cw station responsible was > down at 28.023, at about S9+40 db; by > call, I know the station and > that he is about 3 miles away. > Far enough and weak enough that I > should not be receiving this sort of > interference I think, given > there are no key clicks, etc. > > I turn off the NB, and it clears up > completely, even 500Hz away, > let alone 300 or 400 KHz > away. I go back up, no problem except I > want to use the NB; turn it back on, > problem re-appears. > > This seems to be an artifact of how > the NB is implemented, > rendering it useless under these sorts > of circumstances. > > Am I missing something, out of > adjustment, or ??? > > __ 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 Questions and gripes
Hi All, I just had my first failure on the K3. I noticed both the AF & RF small knobs were slipping so I thought the set screws were loose. But closer examination showed that both knobs were cracked. I replaced them with some small aluminum ones from Radio Shack. I don't think I over tightened the knobs when I built the radio. Is this a problem with other radios? Maybe I got a bad pair. 73 Hardy N7RT - Original Message - From: "David F. Reed" To: "elecraft Reflector" ; Sent: Sunday, December 12, 2010 8:59 AM Subject: [Elecraft] K3 Questions and gripes > Hi folks; > > 2. The power switch - early serial number (1476); my power switch - > well the rubber / plastic part you press on - is starting to look > like a mouse has nibbled on it, with little divots falling off > along the top and right side edges. It is looking quite ragged. > Has anyone else had this, or know if I can replace just the > rubber/plastic part, or do I need to replace the entire switch > assembly? > > Thanks and 73 de Dave, W5SV > __ > 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 Questions and gripes
This is the way most analog noise blankers work. They look at a wide bandwidth to detect noise pulses and if there are loud signals in the range they can be interpreted as noise. The K3 has both an analog and a DSP noise blanker. If there are large nearby signals, you should reduce the aggressiveness of the analog (or 'IF') blanker. You can do this by holding the NB button and then turning the VFO A knob. The DSP noise blanker -- which will not be affected by off-frequency signals -- is adjusted with the VFO B knob. Depending on the type of noise and signals on the band, you will want to use different 'mixes' of analog and DSP noise blanker adjustments. Regarding the power switch, I've found that a cat is highly effective at reducing nibbling by mice (just kidding, ask Elecraft for a fix)! On 12/12/2010 7:59 AM, David F. Reed wrote: > Hi folks; > > Yes, I really love my K3 in spite of my questions and gripes; here they are: > > 1. During the 10 meter contest, I was up around 28.400 operating SSB >with the NB on, when I noticed that I was getting a strong CW >signal pumping my AGC (or so it seemed). > >In doing a little research, I found the cw station responsible was >down at 28.023, at about S9+40 db; by call, I know the station and >that he is about 3 miles away. Far enough and weak enough that I >should not be receiving this sort of interference I think, given >there are no key clicks, etc. > >I turn off the NB, and it clears up completely, even 500Hz away, >let alone 300 or 400 KHz away. I go back up, no problem except I >want to use the NB; turn it back on, problem re-appears. > >This seems to be an artifact of how the NB is implemented, >rendering it useless under these sorts of circumstances. > >Am I missing something, out of adjustment, or ??? > > 2. The power switch - early serial number (1476); my power switch - >well the rubber / plastic part you press on - is starting to look >like a mouse has nibbled on it, with little divots falling off >along the top and right side edges. It is looking quite ragged. >Has anyone else had this, or know if I can replace just the >rubber/plastic part, or do I need to replace the entire switch >assembly? > > Thanks and 73 de Dave, W5SV > __ > 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 -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 Questions and gripes
On Sun, Dec 12, 2010 at 9:59 AM, David F. Reed wrote: > ...with the NB on, when I noticed that I was getting a strong CW > signal pumping Dave, this is gonna happen with any noise blanker. When I turn on NB on my Brand Y radio, I can hear artifacts from a medium strength CW signal 100 kc away -- way worse than the K3. Still, I use NB all the time. There are 2 huge hospitals a few miles away radiating a magnificent panoply of man-made hash, grinding, static, crunches, groans and hisses. In my noisy location, an NB is so valuable that I am just happy to have one that kills the noise; I'll live with the pumping. Tony KT0NY __ 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 Questions and gripes
Hi folks; Yes, I really love my K3 in spite of my questions and gripes; here they are: 1. During the 10 meter contest, I was up around 28.400 operating SSB with the NB on, when I noticed that I was getting a strong CW signal pumping my AGC (or so it seemed). In doing a little research, I found the cw station responsible was down at 28.023, at about S9+40 db; by call, I know the station and that he is about 3 miles away. Far enough and weak enough that I should not be receiving this sort of interference I think, given there are no key clicks, etc. I turn off the NB, and it clears up completely, even 500Hz away, let alone 300 or 400 KHz away. I go back up, no problem except I want to use the NB; turn it back on, problem re-appears. This seems to be an artifact of how the NB is implemented, rendering it useless under these sorts of circumstances. Am I missing something, out of adjustment, or ??? 2. The power switch - early serial number (1476); my power switch - well the rubber / plastic part you press on - is starting to look like a mouse has nibbled on it, with little divots falling off along the top and right side edges. It is looking quite ragged. Has anyone else had this, or know if I can replace just the rubber/plastic part, or do I need to replace the entire switch assembly? Thanks and 73 de Dave, W5SV __ 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
