Re: [Elecraft] K3 sensitivity below 40 meters
I'm glad there are people like you Scott. I'll take back the term 'resonant antenna' and change it to 'good antenna' to keep folks happy. I should have included the word 'system' also. Let's end this before Eric does. Rich, n0ce - Original Message - From: "Scott Manthe" To: Sent: Wednesday, November 14, 2012 12:02 AM Subject: Re: [Elecraft] K3 sensitivity below 40 meters > The real problem is that N0CE made his comment about "resonant" antennas > to protect the feelings of his insecure buddies, at least one of whom > reads this list, so they wouldn't be offended by the fact that his K3 > hears better on 40 meters than the "good equipment" (read: high dollar > rigs) that the rest of his "group" uses. > > To each his own. If it were up to me, I'd get a more secure group to > hang out with. I tell people I know every day how well my K3 works, even > if they own rigs that cost more than twice as much as the K3 does. Of > course, I'm not terribly popular with those guys, either... ;) > > 73, > Scott, N9AA > > > On 11/14/12 12:35 AM, David Gilbert wrote: >> Well ... you made your statement (that even a good receiver needs a >> resonant antenna, and you were talking about how you could hear stations >> breaking in that nobody else could, remember?) to the list so I replied >> to the list. How is that wrong? If I reply to you offline others on >> the list won't realize that you are wrong and the erroneous impressions >> about resonant antennas never die as they should. >> >> > > __ > 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 sensitivity below 40 meters
The real problem is that N0CE made his comment about "resonant" antennas to protect the feelings of his insecure buddies, at least one of whom reads this list, so they wouldn't be offended by the fact that his K3 hears better on 40 meters than the "good equipment" (read: high dollar rigs) that the rest of his "group" uses. To each his own. If it were up to me, I'd get a more secure group to hang out with. I tell people I know every day how well my K3 works, even if they own rigs that cost more than twice as much as the K3 does. Of course, I'm not terribly popular with those guys, either... ;) 73, Scott, N9AA On 11/14/12 12:35 AM, David Gilbert wrote: > Well ... you made your statement (that even a good receiver needs a > resonant antenna, and you were talking about how you could hear stations > breaking in that nobody else could, remember?) to the list so I replied > to the list. How is that wrong? If I reply to you offline others on > the list won't realize that you are wrong and the erroneous impressions > about resonant antennas never die as they should. > > __ 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 sensitivity below 40 meters
Well ... you made your statement (that even a good receiver needs a resonant antenna, and you were talking about how you could hear stations breaking in that nobody else could, remember?) to the list so I replied to the list. How is that wrong? If I reply to you offline others on the list won't realize that you are wrong and the erroneous impressions about resonant antennas never die as they should. But, yes ... there is something inherently wrong with your impression that an antenna system that facilitates maximum transfer of power will also be the best receive antenna. If you reread my comment below you will see that maximum signal-to-noise ratio ... not maximum signal and noise combined ... is what makes a better receive antenna. There is lots of information on the topic of receive antennas all over the internet. You can either research it yourself so that you are able to understand it or not ... your choice. Dave AB7E On 11/13/2012 9:25 PM, Richard Fjeld wrote: > Okay, digest this; my budget allows an 80 meter delta loop fed with > open wire and I tune it with a manual tuner. As far as my radio is > concerned, it looks at a resonant antenna system allowing a maximum > transfer of power on both transmit and receive. Any fault with that > statement? > > We are way off the original post which was asking why he had to "to > engage the 20 dB preamp on the K3 to get it to hear an S9 signal at > the appropriate level of other receivers?" > > Now I know why people reply off line. > > Rich, n0ce > > - Original Message - From: "David Gilbert" > > To: > Sent: Tuesday, November 13, 2012 6:12 PM > Subject: Re: [Elecraft] K3 sensitivity below 40 meters > > >> >> Even that misses the point, I'm afraid. Remember that the original >> comment referred to the receive capability of an antenna. >> >> The only thing that matching or "tuning to resonance" does is improve >> the amplitude of the combined signal and noise feeding the rig ... it >> does not improve the signal to noise ratio. A good receiving antenna, >> however, has some pattern to it that captures the desired signal while >> discriminating against unwanted noise, whether the noise is man made or >> atmospheric. A Beverage antenna, for example, has quite a strong >> pattern in one direction so it has a good signal to noise ratio feeding >> the rig. A Beverage is pretty inefficient, though, and the desired >> signal is pretty weak, so typically a matching transformer (9:1 or so) >> is used to optimize the signal transfer and a low noise preamp (either >> in the rig or external) is also used ... but the signal to noise ratio >> is determined by the antenna independent of whether it is matched or >> not. I guarantee that an unmatched Beverage with enough low noise gain >> after it will outperform any practical resonant or matched ("tuned to >> resonance") antenna available to hams. >> >> 73, >> Dave AB7E >> __ 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 sensitivity below 40 meters
Okay, digest this; my budget allows an 80 meter delta loop fed with open wire and I tune it with a manual tuner. As far as my radio is concerned, it looks at a resonant antenna system allowing a maximum transfer of power on both transmit and receive. Any fault with that statement? We are way off the original post which was asking why he had to "to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at the appropriate level of other receivers?" Now I know why people reply off line. Rich, n0ce - Original Message - From: "David Gilbert" To: Sent: Tuesday, November 13, 2012 6:12 PM Subject: Re: [Elecraft] K3 sensitivity below 40 meters > > Even that misses the point, I'm afraid. Remember that the original > comment referred to the receive capability of an antenna. > > The only thing that matching or "tuning to resonance" does is improve > the amplitude of the combined signal and noise feeding the rig ... it > does not improve the signal to noise ratio. A good receiving antenna, > however, has some pattern to it that captures the desired signal while > discriminating against unwanted noise, whether the noise is man made or > atmospheric. A Beverage antenna, for example, has quite a strong > pattern in one direction so it has a good signal to noise ratio feeding > the rig. A Beverage is pretty inefficient, though, and the desired > signal is pretty weak, so typically a matching transformer (9:1 or so) > is used to optimize the signal transfer and a low noise preamp (either > in the rig or external) is also used ... but the signal to noise ratio > is determined by the antenna independent of whether it is matched or > not. I guarantee that an unmatched Beverage with enough low noise gain > after it will outperform any practical resonant or matched ("tuned to > resonance") antenna available to hams. > > 73, > Dave AB7E > > > > > On 11/13/2012 4:29 PM, Don Wilhelm wrote: >> Yes, I agree. >> >> Given a bit of "benefit of doubt", I would think the poster would have >> better said, an antenna "tuned to resonance" rather than a resonant >> antenna. >> Many very good antennas are not inherently resonant, but resonance (and >> therefore good power transfer) is achieved by means of some kind of >> tuning mechanism. >> >> 73, >> Don W3FPR >> >> On 11/13/2012 6:21 PM, David Gilbert wrote: >>> Particularly as far as receiving goes, that's a totally erroneous >>> statement that has been dispelled many, many times. There is nothing >>> magical or beneficial about a resonant antenna short of the fact that it >>> sometimes makes it easier to match. Check out how (and how well) a >>> Beverage antenna or one of the flag/pennant antennas work for receiving >>> to see the fallacy of your comment. >>> >>> The key to a good receive antenna is having a pattern that discriminates >>> against QRM or QRN as the case may be. As long as there is enough low >>> noise gain after the antenna all else is misconception. >>> >>> Dave AB7E >>> >>> >>> >>> On 11/13/2012 12:13 PM, Richard Fjeld wrote: >>>> In summary, even a good radio needs a resonant antenna. >>>> >>>> Rich, n0ce >>>> >> __ >> 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 sensitivity below 40 meters
Even that misses the point, I'm afraid. Remember that the original comment referred to the receive capability of an antenna. The only thing that matching or "tuning to resonance" does is improve the amplitude of the combined signal and noise feeding the rig ... it does not improve the signal to noise ratio. A good receiving antenna, however, has some pattern to it that captures the desired signal while discriminating against unwanted noise, whether the noise is man made or atmospheric. A Beverage antenna, for example, has quite a strong pattern in one direction so it has a good signal to noise ratio feeding the rig. A Beverage is pretty inefficient, though, and the desired signal is pretty weak, so typically a matching transformer (9:1 or so) is used to optimize the signal transfer and a low noise preamp (either in the rig or external) is also used ... but the signal to noise ratio is determined by the antenna independent of whether it is matched or not. I guarantee that an unmatched Beverage with enough low noise gain after it will outperform any practical resonant or matched ("tuned to resonance") antenna available to hams. 73, Dave AB7E On 11/13/2012 4:29 PM, Don Wilhelm wrote: > Yes, I agree. > > Given a bit of "benefit of doubt", I would think the poster would have > better said, an antenna "tuned to resonance" rather than a resonant antenna. > Many very good antennas are not inherently resonant, but resonance (and > therefore good power transfer) is achieved by means of some kind of > tuning mechanism. > > 73, > Don W3FPR > > On 11/13/2012 6:21 PM, David Gilbert wrote: >> Particularly as far as receiving goes, that's a totally erroneous >> statement that has been dispelled many, many times. There is nothing >> magical or beneficial about a resonant antenna short of the fact that it >> sometimes makes it easier to match. Check out how (and how well) a >> Beverage antenna or one of the flag/pennant antennas work for receiving >> to see the fallacy of your comment. >> >> The key to a good receive antenna is having a pattern that discriminates >> against QRM or QRN as the case may be. As long as there is enough low >> noise gain after the antenna all else is misconception. >> >> Dave AB7E >> >> >> >> On 11/13/2012 12:13 PM, Richard Fjeld wrote: >>> In summary, even a good radio needs a resonant antenna. >>> >>> Rich, n0ce >>> > __ > 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 sensitivity below 40 meters
Yes, I agree. Given a bit of "benefit of doubt", I would think the poster would have better said, an antenna "tuned to resonance" rather than a resonant antenna. Many very good antennas are not inherently resonant, but resonance (and therefore good power transfer) is achieved by means of some kind of tuning mechanism. 73, Don W3FPR On 11/13/2012 6:21 PM, David Gilbert wrote: > Particularly as far as receiving goes, that's a totally erroneous > statement that has been dispelled many, many times. There is nothing > magical or beneficial about a resonant antenna short of the fact that it > sometimes makes it easier to match. Check out how (and how well) a > Beverage antenna or one of the flag/pennant antennas work for receiving > to see the fallacy of your comment. > > The key to a good receive antenna is having a pattern that discriminates > against QRM or QRN as the case may be. As long as there is enough low > noise gain after the antenna all else is misconception. > > Dave AB7E > > > > On 11/13/2012 12:13 PM, Richard Fjeld wrote: >> In summary, even a good radio needs a resonant antenna. >> >> Rich, n0ce >> __ 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 sensitivity below 40 meters
Particularly as far as receiving goes, that's a totally erroneous statement that has been dispelled many, many times. There is nothing magical or beneficial about a resonant antenna short of the fact that it sometimes makes it easier to match. Check out how (and how well) a Beverage antenna or one of the flag/pennant antennas work for receiving to see the fallacy of your comment. The key to a good receive antenna is having a pattern that discriminates against QRM or QRN as the case may be. As long as there is enough low noise gain after the antenna all else is misconception. Dave AB7E On 11/13/2012 12:13 PM, Richard Fjeld wrote: > > In summary, even a good radio needs a resonant antenna. > > Rich, n0ce > __ 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 sensitivity below 40 meters
> > In summary, even a good radio needs a resonant antenna. > Nah. Rick K2XT __ 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 sensitivity below 40 meters
On Tue, Nov 13, 2012 at 1:13 PM, Richard Fjeld wrote: > ...even a good radio needs a resonant antenna. > = It's true that reception is often better if the antenna is matched, but this doesn't mean that the antenna has to be resonant. An antenna's resonance or non-resonance does not determine its gain or directivity. It only determines whether or not it presents a reactive load at its input terminals. If an antenna does present a reactive load, a tuner can match it so that the receiver sees the correct resistive impedance. You will hear a lot more with a non-resonant curtain, rhombic or log-periodic aimed in the right direction than you will with a resonant ground-plane. A half-hour spent with EZNec looking at the gain and radiation patterns of long-wire antennas of various lengths will dispel many misconceptions. Tony KT0NY -- http://www.isb.edu/faculty/facultydir.aspx?ddlFaculty=352 __ 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 sensitivity below 40 meters
Yes, good point. I assumed when I should have been more specific. With the P3, I have the best of both worlds. I 'presume' most K3's are adjusted from the factory per the manual with the pre-amp on, at -50 uV = S9. Rich, n0ce - Original Message - From: "Don Wilhelm" To: Sent: Tuesday, November 13, 2012 12:05 PM Subject: Re: [Elecraft] K3 sensitivity below 40 meters > The K3 S-meter can be calibrated with either the preamp on or off. I run > with SMTR MD set to ABS, and I calibrate the S-meter with the preamp > off because of that. > > 73, > Don W3FPR > > __ 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 sensitivity below 40 meters
In all fairness, I have to append this. I held off saying what I wanted to because I knew of someone who would be watching this reflector, and I didn't want my comments out to 'the group'. I said "I believe it is due to resonance" and it is as far as the antenna is concerned. I also believe it is due to the K3. I bought it for my last sun cycle, and it has been a pure enjoyment for me. I'm not a 'nectar' drinker, if you get the connection. It just wouldn't be right to not acknowledge the excellent receiver. The NR is effective for man-made noise. I would like to see it better on atmospheric noise, but I don't know if that will be possible. I bought the K3 for it's operating conveniences, and it's reputation as a good receiver which I have found to be accurate. I am especially pleased with the filtering. Since I got the P3 and can see the signals beside my passband that I am not hearing, I have been amazed. In summary, even a good radio needs a resonant antenna. Rich, n0ce - Original Message - From: "Richard Fjeld" To: Cc: "elecraft posting" Sent: Tuesday, November 13, 2012 11:39 AM Subject: Re: [Elecraft] K3 sensitivity below 40 meters >I think it may be due to my final comment, but first, some info. > > My pre-amp is off and the ATT is on 90% of the time. I seldom turn on the > pre-amp. With the pre-amp off, and the ATT on, I consistently hear guys > breaking in that the others in the group do not hear, and they run good > equipment. They comment on it, and believe it is due to my antenna. The > apex of my antenna is only 40 feet high. One of them has a 100 foot tower. > I believe it is due to resonance. Read on. > > I would suspect antenna not resonant, or working with a swr that is not > optimum for the frequency. (You need both.) Emphasis is given to swr > for > transmit out of concern for the finals, but I discovered years ago how > important a 1.0:1 swr is for receive. Anything less is a compromise in > receive performance. > > You say "to 'hear' an S9 signal". That has me curious. S9 is RF, hearing > is AF. Still pondering > > The K3 is calibrated for S9 at -50 uV with the pre-amp on. This may be the > answer to your question. It could also be that you need to calibrate your > S-meter. The XG-2 works well for that. > > Good luck, > Rich, n0ce > > > - Original Message - > From: > To: > Sent: Tuesday, November 13, 2012 8:39 AM > Subject: [Elecraft] K3 sensitivity below 40 meters > > >> >> Conventional wisdom historically has been that a receiver preamp is not >> used at 40 meters and below primarily because it is not needed, indeed >> it would typically degrade receiver performance. So why is it necessary >> to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at >> the appropriate level of other receivers? >> __ >> 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 sensitivity below 40 meters
The K3 S-meter can be calibrated with either the preamp on or off. I run with SMTR MD set to ABS, and I calibrate the S-meter with the preamp off because of that. 73, Don W3FPR On 11/13/2012 12:39 PM, Richard Fjeld wrote: > I think it may be due to my final comment, but first, some info. > > My pre-amp is off and the ATT is on 90% of the time. I seldom turn on the > pre-amp. With the pre-amp off, and the ATT on, I consistently hear guys > breaking in that the others in the group do not hear, and they run good > equipment. They comment on it, and believe it is due to my antenna. The > apex of my antenna is only 40 feet high. One of them has a 100 foot tower. > I believe it is due to resonance. Read on. > > I would suspect antenna not resonant, or working with a swr that is not > optimum for the frequency. (You need both.) Emphasis is given to swr for > transmit out of concern for the finals, but I discovered years ago how > important a 1.0:1 swr is for receive. Anything less is a compromise in > receive performance. > > You say "to 'hear' an S9 signal". That has me curious. S9 is RF, hearing > is AF. Still pondering > > The K3 is calibrated for S9 at -50 uV with the pre-amp on. This may be the > answer to your question. It could also be that you need to calibrate your > S-meter. The XG-2 works well for that. > > __ 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 sensitivity below 40 meters
Preamp on K3 is 11 dB, not 20. The range, using preamp or ATT, is 20 dB. I always run the attenuator on 160 and 80 TX antennas, and the preamp on some of my listening antennas. 73, Guy On Tue, Nov 13, 2012 at 9:39 AM, wrote: > > Conventional wisdom historically has been that a receiver preamp is not > used at 40 meters and below primarily because it is not needed, indeed > it would typically degrade receiver performance. So why is it necessary > to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at > the appropriate level of other receivers? > __ > 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 sensitivity below 40 meters
I think it may be due to my final comment, but first, some info. My pre-amp is off and the ATT is on 90% of the time. I seldom turn on the pre-amp. With the pre-amp off, and the ATT on, I consistently hear guys breaking in that the others in the group do not hear, and they run good equipment. They comment on it, and believe it is due to my antenna. The apex of my antenna is only 40 feet high. One of them has a 100 foot tower. I believe it is due to resonance. Read on. I would suspect antenna not resonant, or working with a swr that is not optimum for the frequency. (You need both.) Emphasis is given to swr for transmit out of concern for the finals, but I discovered years ago how important a 1.0:1 swr is for receive. Anything less is a compromise in receive performance. You say "to 'hear' an S9 signal". That has me curious. S9 is RF, hearing is AF. Still pondering The K3 is calibrated for S9 at -50 uV with the pre-amp on. This may be the answer to your question. It could also be that you need to calibrate your S-meter. The XG-2 works well for that. Good luck, Rich, n0ce - Original Message - From: To: Sent: Tuesday, November 13, 2012 8:39 AM Subject: [Elecraft] K3 sensitivity below 40 meters > > Conventional wisdom historically has been that a receiver preamp is not > used at 40 meters and below primarily because it is not needed, indeed > it would typically degrade receiver performance. So why is it necessary > to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at > the appropriate level of other receivers? > __ > 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 sensitivity below 40 meters
On my FTDX-5000MP I never had the preamp on for anything below 40m all it did was increase noise. All that was ever done was to use the DNR to bring the signal up out of the noise floor a lot of the time for a signal only saw on a spot you had to bring it find it with the DNR on that frequency. As I have said this is a point that the 5000 does better than my K3's about the only one though. -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of k...@charter.net Sent: Tuesday, November 13, 2012 8:39 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3 sensitivity below 40 meters Conventional wisdom historically has been that a receiver preamp is not used at 40 meters and below primarily because it is not needed, indeed it would typically degrade receiver performance. So why is it necessary to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at the appropriate level of other receivers? __ 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 sensitivity below 40 meters
The original question was *NOT* about the K3, but the KX3 which is different than the K3 due to a different design architecture. 73, Don W3FPR On 11/13/2012 9:39 AM, k...@charter.net wrote: > Conventional wisdom historically has been that a receiver preamp is not > used at 40 meters and below primarily because it is not needed, indeed > it would typically degrade receiver performance. So why is it necessary > to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at > the appropriate level of other receivers? > __ 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 sensitivity below 40 meters
Conventional wisdom historically has been that a receiver preamp is not used at 40 meters and below primarily because it is not needed, indeed it would typically degrade receiver performance. So why is it necessary to engage the 20 dB preamp on the K3 to get it to hear an S9 signal at the appropriate level of other receivers? __ 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