K3 and phase noise
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WA6HHQ:
>They are now making the dynamic range measurements by measuring the on frequency IMD spur or blocked signal using a narrow band spectrum analyzer. This separates the blocking or IMD measurement from reciprocal mixing, which they will do as an additional test. I suppose this means no ARRL measurements will ever again say "noise limited", but I question how practical this is in the real world. In the latter, we want to know when any spurious signal will cover a weak signal at the noise floor...whether it's IMD, BDR or phase noise. I like the term G3SJX uses (he does RSGB's Radcom product reviews)...Spurious Free Dynamic Range (SFDR)...which encompasses all potential sources of spurious effects. I will note that the K3 may still have better overall phase noise than the other rigs listed if you integrate it over the potential bandwidth of phase noise interference. In a typical contest situation, you may have strong signals +/-25 kHz of your RX frequency. In this case, phase noise from a station 25 kHz away can still cause problems. For example, comparing to Orion: Rig 1kHz 2 10 20 50 100 1M K3 -110 -119 -136 -140 -143 -144 -150 ORION 2 -121 -129 -126 -125 -118 -128 -138 Delta -11 -10 +10 +15 +25 +26 +12 it is ~10 dB better at close spacings, but 10-25 dB worse at wider spacings (and over much greater BW than the K3). Assuming you had strong signals spaced every 1 kHz over +/-25 kHz (not unusual in a major CW contest), the K3's *integrated* phase noise effect could be less than Orion's. Also I'm sure the VHF guys will love the K3's numbers, since they are more interested in the wide-spaced phase noise effects. The other thing all of us need to remember about extremely close spaced measurements is that these are made with continuous carriers (i.e. no key clicks) from ultra-quiet sources (e.g. HP 8640Bs or quartz oscillators). In the real world, nearby signals will have much more noise from clicks and their own TX phase noise. This is why we are kidding ourselves if we think a 200-250 Hz roofing filter will actually help much more than a 500 Hz filter. "Theoretically" it might be better, but in the real world of key clicks and TX phase noise, that will far override any theoretical advantage of the narrower filter IMHO. Thanks for posting the data...maybe a little worse than I had hoped for at close spacings but as I think about it (e.g. above), it may actually yield a better overall result for integrated phase noise effects. 73, Bill W4ZV _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Bill Tippett wrote:
> The other thing all of us need to remember about > extremely close spaced measurements is that these are > made with continuous carriers (i.e. no key clicks) from > ultra-quiet sources (e.g. HP 8640Bs or quartz oscillators). > In the real world, nearby signals will have much more > noise from clicks and their own TX phase noise. Bill, If you integrate total world-wide TX phase noise and clicks on 20 m now, then do it again after we've shipped our first two batches of K3s, one would hope to see a healthy decrease. This is left as an exercise for the reader :) 73, Wayne N6KR --- http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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On 9/21/07, wayne burdick <[hidden email]> wrote:
> If you integrate total world-wide TX phase noise and clicks on 20 m > now, then do it again after we've shipped our first two batches of K3s, > one would hope to see a healthy decrease. Not to worry...I'm going to set up a company to sell "phase noise offsets" to non-K3 users. :-) 73, Bill _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Hello again,
thanks for "Phase noise" data and discussion. What I am now looking for are some other informations important for using K3 as I/F for serious VHF/UHF/SHF contesting/DXing. First question is about display readout in "transvertor" mode - is there possible some offset - for example 144 000.00 is on 28 001.15 ? Second question - maybe more general - is about TX possibilities outside standard HAM Bands. For example if my 2m transvertor is built for 26MHz (26MHz/144MHz instead of stadard 28/144). The reason is that the rest of line (transvertors from 1296MHz up) are built to use I/F 145, 146 and 147MHz - normally when 144 is on 28 there is no way to use 31MHz on standard gears, but with some mods is possible to use any lower frq. up to 30MHz. Thanks for any info or link to such info, 73! Lexa, ok1dst _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Fwd: K3 and phase noise
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In reply to this post by Bill W4ZV
On 9/21/07, Bill Tippett <[hidden email]> wrote:
> Not to worry...I'm going to set up a company to sell "phase noise > offsets" to non-K3 users. :-) Any discounts being offered to those of us who live in the first hop zone of Eu 40m BC stations, and who use 7130 - 7200 kHz? Number of stations : Too many. Carrier levels : Can reach -10 / -5dbm at Rx. BC Tx Phase Noise : At times a problem. Modulation : Enthusiastic with pop music especially, another problem. 73, Geoff GM4ESD _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Alexandr Kobranov
Hallo,
> Second question - maybe more general - is about TX possibilities outside > standard HAM Bands. For example if my 2m transvertor is built for 26MHz > (26MHz/144MHz instead of stadard 28/144). I've also asked, a long time ago, about using "non-standard" IFs for transverters with the K3; my suggestion being somewhere between 30 and 50MHz. I never really got an answer and I wonder if the VFO in the K3 could handle low VHF IFs. For RX I do not think that 26MHz should be a problem but for TX it very well may be, because AFAIK there are legal and moral issues with K3 transmit capability in the CB (and so called Free Band) frequency range. I feel that allowing low power IFs outside of the HF bands with the transverter interface is a very good idea, e.g. an IF of 30 to 40 MHz would not conflict with a 10m station at the same QTH and is wide enough for the entire 70cm band in Europe. vy 73 de toby _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K3 transvertor mode question
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Hi Toby,
I do not believe that there is many such requests for having I/F TX/RX in segment from 30 to 50MHz. The reason is that dozen of standard RIGs are after some mods able to go from 1 to 30MHz without problems and a lot transvertor systems already made are counting with this. Additionally a lot HF rigs are "optimized" for some band(-s) - 14MHz or 21MHz. There are sometimes better results then on the rest of bands. And - as I believe is the case o K3 also - the modification for TX/RX in entire limits is more cheaper and technically easier. But maybe I am wrong! So want to know how this "problem" can be handled by K3 ans I know several other guys running serious VHF/UHF/SHF gears with a lot of interest in K3 performance. So staying tuned for some K3 user comment or is anywhere OperationalManual to study - not found on Elecraft Web ? (and not disturb whole rest of world :-)) 73! Lexa, ok1dst [hidden email] napsal(a): > Hallo, > >> Second question - maybe more general - is about TX possibilities outside >> standard HAM Bands. For example if my 2m transvertor is built for 26MHz >> (26MHz/144MHz instead of stadard 28/144). > > I've also asked, a long time ago, about using "non-standard" IFs for > transverters with the K3; my suggestion being somewhere between 30 and 50MHz. I > never really got an answer and I wonder if the VFO in the K3 could handle low > VHF IFs. > > For RX I do not think that 26MHz should be a problem but for TX it very well may > be, because AFAIK there are legal and moral issues with K3 transmit capability > in the CB (and so called Free Band) frequency range. > > I feel that allowing low power IFs outside of the HF bands with the transverter > interface is a very good idea, e.g. an IF of 30 to 40 MHz would not conflict > with a 10m station at the same QTH and is wide enough for the entire 70cm band > in Europe. > > vy 73 de toby > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Ahoj Lexa,
> I do not believe that there is many such requests for having ... I agree with you that most standard rigs will not go above 30MHz and often do better on 14MHz or 21MHz than they do on 28MHz. I would hope that the K3 does show major differences in its performance from band to band. I do think that using low VHF for the IF could make good sense, assuming of course that the IF transceiver does a good job at these frequencies. > are after some mods able to go from 1 to 30MHz ... If I remember correctly, Wayne has written in the past that the K3 will not transmit in the CB range and that this blocked by the firmware. The firmware will not be released, i.e. user firmware modifications are not possible. At least not without a lot of reverse engineering. Also I believe that Wayne also wrote that Elecraft will compile different versions of the firmware with feature adjustments depending on the local laws of where the K3 is going to be used. > OperationalManual to study - not found on Elecraft Web ? ... I am sure that the manual will be downloadable soon - a fortnight or so? vy 73 de toby _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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.. better on 14MHz or 21MHz than they do on 28MHz. I would hope that the K3
does not show major differences in its performance ... and not .. better on 14MHz or 21MHz than they do on 28MHz. I would hope that the K3 does show major differences in its performance ... sri de toby _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K3 transvertor mode question
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In reply to this post by dj7mgq
Concerning TX/RX out of ham bands:
Maybe there is some way thanks to firmware - allow general coverage ONLY in transvertor mode. Maybe some wish-list is there... About offset - if it is the same as on K2 it is +-9,99kHz so sometimes it is enough. Maybe it is not the same as on K2, who knows... 73! Lexa, ok1dst [hidden email] napsal(a): > Ahoj Lexa, > >> I do not believe that there is many such requests for having ... > > I agree with you that most standard rigs will not go above 30MHz and often do > better on 14MHz or 21MHz than they do on 28MHz. I would hope that the K3 does > show major differences in its performance from band to band. I do think that > using low VHF for the IF could make good sense, assuming of course that the IF > transceiver does a good job at these frequencies. > > >> are after some mods able to go from 1 to 30MHz ... > > If I remember correctly, Wayne has written in the past that the K3 will not > transmit in the CB range and that this blocked by the firmware. The firmware > will not be released, i.e. user firmware modifications are not possible. At > least not without a lot of reverse engineering. Also I believe that Wayne also > wrote that Elecraft will compile different versions of the firmware with feature > adjustments depending on the local laws of where the K3 is going to be used. > > >> OperationalManual to study - not found on Elecraft Web ? ... > > I am sure that the manual will be downloadable soon - a fortnight or so? > > > vy 73 de toby > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Geoffrey Mackenzie-Kennedy-2
Between the broadcasters, and band plan conflicts between countries, 40m
here on the east coast, to me at least, has been practically worthless. Down to about 25KC of useful air. David Wilburn [hidden email] K4DGW K2 #5982 FP#-1751 Geoffrey Mackenzie-Kennedy wrote: > On 9/21/07, Bill Tippett <[hidden email]> wrote: > >> Not to worry...I'm going to set up a company to sell "phase noise >> offsets" to non-K3 users. :-) > > Any discounts being offered to those of us who live in the first hop > zone of Eu 40m BC stations, and who use 7130 - 7200 kHz? > > Number of stations : Too many. > Carrier levels : Can reach -10 / -5dbm at Rx. > BC Tx Phase Noise : At times a problem. > Modulation : Enthusiastic with pop music especially, > another problem. > > > 73, > Geoff > GM4ESD > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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Also meant to say, sorry to hear about your location, sounds worse than
what we have. David Wilburn [hidden email] K4DGW K2 #5982 FP#-1751 David Wilburn wrote: > Between the broadcasters, and band plan conflicts between countries, 40m > here on the east coast, to me at least, has been practically worthless. > Down to about 25KC of useful air. > > David Wilburn > [hidden email] > K4DGW > K2 #5982 > FP#-1751 > > > Geoffrey Mackenzie-Kennedy wrote: >> On 9/21/07, Bill Tippett <[hidden email]> wrote: >> >>> Not to worry...I'm going to set up a company to sell "phase noise >>> offsets" to non-K3 users. :-) >> >> Any discounts being offered to those of us who live in the first hop >> zone of Eu 40m BC stations, and who use 7130 - 7200 kHz? >> >> Number of stations : Too many. >> Carrier levels : Can reach -10 / -5dbm at Rx. >> BC Tx Phase Noise : At times a problem. >> Modulation : Enthusiastic with pop music especially, >> another problem. >> >> >> 73, >> Geoff >> GM4ESD >> >> _______________________________________________ >> Elecraft mailing list >> Post to: [hidden email] >> You must be a subscriber to post to the list. >> Subscriber Info (Addr. Change, sub, unsub etc.): >> http://mailman.qth.net/mailman/listinfo/elecraft Help: >> http://mailman.qth.net/subscribers.htm >> Elecraft web page: http://www.elecraft.com >> > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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