[Elecraft] K3 KRX3 with only 6kHz filter
I know that the K3 needs a 2.7 or 2.8 filter so it can transmit CW and SSB, but I don't see that applying for the KRX3. Would the KRX3 work with only a 6 kHz filter, and would Elecraft sell it with a credit for upgrading from the 2.7 to the 6.0? 73, Erik K7TV -- View this message in context: http://n2.nabble.com/K3-KRX3-with-only-6kHz-filter-tp1569574p1569574.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 panadapter choices
Hi Dave, The Perseus certainly seems impressive. As a second receiver it would cost only $151 more than the KRX3, if the latter is stuffed with all the filters I have now added to my K3. I will be very interested in your experience with it in the CQ WW CW. Please report the average and peak number of strength of the strongest signals at your location, across the whole HF spectrum, if that is practical. When you say "click and go" I assume the Perseus software is tuning the K3. Are you saying that *no* adjustment is needed to get the right pitch for SSB or CW? I have the kits for SoftRock Lite and the isolation amplifier sitting here, just waiting to be put together, so I will definitely give that a go first. I too don't much like the idea of getting an outboard soundcard, so if the soundcard is the weakest link (in desktop and/or laptop) I don't know if I will take that step or go to something not requiring a soundcard. There is no doubt that a receiver for the full HF range is worth more than just a panadapter. One slight count against the Perseus might be that it requires a power connection. Is it tolerant enough as to voltages to be run from either the typical home station 13.8V supply, or a car battery being discharged to 11 V or so? 73, Erik K7TV - Original Message - From: G4AON (via Nabble) To: K7TV Sent: Friday, November 14, 2008 11:07 AM Subject: Re: [Elecraft] K3 panadapter choices Erik (and Julian) I'm posting only on Nabble as the Mailman Reflector seems to be broken at my end today... I was looking for a low cost panadapter for my K3 and kept finding issues, there was the IF leakage/spurious injection issue, "low sensitivity" when using the K3 IF out, "my soundcard isn't good enough" so I might need an outboard soundcard, will 192 KHz span be enough? And so I kept having doubts. A friend recently bought a Perseus that he found outperformed his TS480. The Perseus at that time covered an 800 KHz span and was a direct connection to USB2 and was available for next day delivery from a UK source... Span is now up to 1600 KHz. Having a high specification panoramic receiver has been an eye opener for me, maybe next weekend the CQ WW CW contest will cause the Perseus to struggle compared to the K3 but we will see, it's certainly holding it's own so far. The screen resolution is good enough to "click and go" on pretty much all CW and SSB signals at 100 KHz resolution without needing fine tuning, wider spans usually need a tweak but this could easily improve if/when the screen display is increased in size from it's present 1024 pixels wide. I don't connect my Perseus to the K3 IF, it connects in parallel via a ferrite splitter using the RX RF IN/OUT sockets on the KXV3. For my money the Perseus makes a good 2nd receiver, certainly it compares favourably on cost against the K3 second receiver (with a 2.8 KHz and 400 Hz filter installed) when you include shipping and tax. I haven't used any of the low cost alternatives, but the Perseus certainly impresses me. 73 Dave, G4AON K3/100 #80 -- K7TV wrote: Researching my options for a K3 panadapter (Softrock, LP-PAN, SDR-IQ, Perseus, Mercury...) I want to thank Paul W9AC for sharing his experience with the SDR-IQ on the list: "When observing signal strength on the display, there's ample resolution for signal comparisons. SDR-IQ is powered from the PC's USB port, so only two connections are made (I.F. and USB). SpectraVue supports the K3 and using the "point 'n click" feature has been great. Click on the display and the K3 instantly moves to that frequency. The only shortcoming I've found is that SpectraVue needs to poll the K3's mode offset data so that changing modes does not require an offset change in SpectraVue. Not sure if that's handled automatically when using LP-PAN and PowerSDR." I would be very interested to read similar detail about the other possible hardware and software choices. An overview table showing which spectrum analysis software packages work with which hardware choices would be very helpful. As long as a the hardware is used for spectrum display (not as a receiver to be listened to) it seems to me that hardware in the low to middle price range is good enough. The issue then is the software choice first and then finding hardware compatible with the software. When choosing software I would really like to know if there is any package available today that already adjusts for the mode offset, or is planned to do so in the near future. A wide and narrow spectrum display window may also be a positive feature in comparing one software package to another, especially if one is going to run other software at the same
[Elecraft] K3 panadapter choices
Researching my options for a K3 panadapter (Softrock, LP-PAN, SDR-IQ, Perseus, Mercury...) I want to thank Paul W9AC for sharing his experience with the SDR-IQ on the list: "When observing signal strength on the display, there's ample resolution for signal comparisons. SDR-IQ is powered from the PC's USB port, so only two connections are made (I.F. and USB). SpectraVue supports the K3 and using the "point 'n click" feature has been great. Click on the display and the K3 instantly moves to that frequency. The only shortcoming I've found is that SpectraVue needs to poll the K3's mode offset data so that changing modes does not require an offset change in SpectraVue. Not sure if that's handled automatically when using LP-PAN and PowerSDR." I would be very interested to read similar detail about the other possible hardware and software choices. An overview table showing which spectrum analysis software packages work with which hardware choices would be very helpful. As long as a the hardware is used for spectrum display (not as a receiver to be listened to) it seems to me that hardware in the low to middle price range is good enough. The issue then is the software choice first and then finding hardware compatible with the software. When choosing software I would really like to know if there is any package available today that already adjusts for the mode offset, or is planned to do so in the near future. A wide and narrow spectrum display window may also be a positive feature in comparing one software package to another, especially if one is going to run other software at the same time. If one contemplates actually listening to the outboard SDR, it seems that more money does buy better performance, although probably none of the reasonable hardware choices will be as good in some contests as the second receiver option of the K3, which has roofing filters. On the other hand, it would hardly be practical for an assistant operator to reach the K3 controls to make use of the second receiver, while the computer controlling an outboard SDR could easily be used by an assistant operator. (Of course depending on the contest, this may or may not be legal for a given entry class.) Maybe the second RX in a K3 could be run from a computer while the rig is otherwise run from the front panel? Maybe two computers (one per operator) could be used to control the K3 with second RX. I don't have experience with the various rig control software available, so I hope someone can enlighten me. 73, Erik K7TV -- View this message in context: http://n2.nabble.com/K3-panadapter-choices-tp1495993p1495993.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
I just came across another situation where the K3 S-meter wasn't doing the job. Bought an MFJ noise canceller (works at receive frequency, using a separate noise pickup antenna). The reason that the purchase came about *now* was that, unlike my other rigs, the K3 has this wonderful RX antenna loop, where the noise canceller can be inserted without worries about transmitting through it. On the device you adjust an amplitude control for each antenna such that the noise signal has the same amplitude from both antennas, and then you adjust a phasing control to null out the noise signal. Well, guess, what? Both for the amplitude matching and for nulling an S-meter showing a small differences such as 1 dB is highly desirable. While this can occasionally be done for distant unwanted signals, the main usefulness of the device is for when the amplitude and phase relationships are constant, i.e. for local noise sources. Thus there is no QSB to dither the reading between full S-units - with only full S-units shown you have no idea if you are 6 dB or 1 dB from the next step. If you don't see a small decrease when approaching the null, you are likely to turn the knob too fast and miss the null altogether. My workaround was to turn off AGC and listen for the volume changes. I deemed the built-in audio level meter to be too slow. To to what almost any radio would let me do by just watching the S-meter, I had one button press to turn off the AGC, one shock to my ears, one adjustment to RF gain, one button press to turn on AGC and one readjustment of RF gain. A computer program displaying the S-meter output from the K3 is no help in this situation, as it only sees whole S-units, and with no QSB it won't bounce between those steps. A panoramic display is probably helpful, and this experience gives me another reason to get one. However, after I spent the day using the computer for other work, I usually feel to lazy to turn on ham radio software just to relax from the computer by doing some some ham radio. Also, I always do Field Day with a group that lets me bring my own radio but has no power source to power my laptop. (Logging is done using an ancient DOS FD logging program, running on a small old laptop to which I don't have access for installing panoramic software (nor any other software that might complement the functionality of the K3). 73, Erik K7TV David Cutter wrote: > > Agreed > > >> A calibrated S meter could be useful tool in many other ways. >> >> - Measuring field strength and patterns of antennas. >> >> - Reporting on things like BPL and other radiated and conducted >> measurements that seem to be a daily threat on HF. Just knowing they >> close >> to S9 plus plus minus 20 db is not a professional way to build an >> argument against such pollution in professional circles. Having a >> calibrated S meter and adding something a like calibrated loop with a >> known antenna factor would make collecting and surveying potential RF >> pollution data very easy. While we don't need 0.1 db accuracy 1 db of >> accuracy is easily achieved in SDR radios. >> >> http://www.vk1od.net/bpl/QueanbeyanBplTrial2.htm >> >> - Using a good S-meter would also be a reliable way of surveying a >> potential new QTH. The data could be used to compare signal noise levels >> to the thermal noise floor, or even compare what you are measuring to the >> surveyed ITU noise levels on HF. It would be nice knowing that your >> potential new QTH is in a QRM silent location. It would also be good >> comparing noise floors amongst hams for various locations. >> >> - It would also be useful knowing how accurate and reliable propagation >> programs are on a daily basis since they do predict signal levels. This >> might come in handy if one wanted to build a DSP based DF system which >> relies on ionospheric data. >> >> - As a general level meter around the shack, it could even be used as an >> accurate power meter. >> >> So to me a well calibrated S-meter can take the place of many expensive >> instruments that most hams dont have access to on a daily basis. It is a >> very useful tool. When we use some sort of absolute reference our >> understanding of what we are measuring on a daily basis increases our >> understanding of what we are doing in our hobby. >> >> While we on this subject if further work is carried out on the K3's >> s-meter you might as well follow the IARU's recommendation for S-meters >> and make it quasi peak in nature. >> >> Besides these days, with the competition increasing in the new radio >> market with radios like the Perseus, ADAT and the newly released cheap >> Flexrad
[Elecraft] K3 TX equalizer messes up PSK
Tonight I was on 40 PSK31 using DATA A. At one point I was wondering why in the world I wasn't getting enought power out. It turned out I had clicked on a different frequency in the waterfall! Clearing the TX equalizer fixed the problem. This is not the first time this has happened to me. Then when I want to use phone I have to input 8 settings for the equalizer again. It would be great if the TX equalizer could have separate settings per mode, but I would be happy if just the equalizer were bypassed in DATA A. I think something along these lines should be a high priority. 73, Erik K7TV -- View this message in context: http://n2.nabble.com/K3-TX-equalizer-messes-up-PSK-tp1463887p1463887.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
Guy, I too would like that capability, *but* it would not make sense to use the K3 this way unless it has the long term gain stability (including vs. temperature changes) to support it. In response to my raising that issue, Geoff (GM4ESD) emailed me off list to suggest that the J-FET used used in the K3 signal chain before the DSP (used in the hardware AGC loop unless I am mistaken) may be a source of gain variation with temperature. On the other hand, I would think that the K3 receive gain would be more stable against temperature variations than an analog receiver that might have many more stages that are susceptible. I don't know if the K3 hardware is stable enough to be used as a calibrated uV meter. If it is, then no doubt we will eventually see software and firmware to make use of it. If not, then I would not fault Wayne, since a designer cannot please everybody, and he must design for the goals that make economic sense to him. It has been pointed out that some software defined receivers (presumably without analog stages) can function well as calibrated signal strenght meters for received signals. Personally I would want something like that anyway, for the panoramic reception capability, so that makes me less impatient for the K3 to be proven as or disproven as a precision RF voltmeter. (I would still like to have a high-resolution S-meter, though, inaccurate or not. Thanks Don Rasmussen for sharing your approach.). I have a SoftRock Lite in the pipeline for a first panadapter attempt. The price of that is so low that it isn't very important whether it is good enough or not. If it is not, I will just move on to something better. It would be interesting to know what you give up if you get, say, an SDR-IQ vs. a Perseus. Of course the LP-Pan is also an alternative. 73, Erik K7TV I'd like to be able to calibrate it to 1 uV and 50 uV and know that the noise on the band is -10 or +3 dBuV and that the signal from a friend has gone down to +18 from +26 last week and previous. That requires a calibration, and while one could just use what the rig does naturally as a reference, the K3 has changing SDR code, and maintaining a calibration on a reference source sure does simplify things. To another objection earlier in the thread, inexpensive test equipment doesn't have selectability to narrow down on a single CW signal. So I'm looking at the firmware only abilities (not hardware) of a K3 to do something that has always been a bear. Other SDR's have it, so I figure Wayne will get to it in time, and I will have a piece of on-the-air test gear that I've never had, and prior to now couldn't get without taking out a mortgage. 73, Guy. -- View this message in context: http://n2.nabble.com/Bigger-K3-S-meter-tp1399030p1442642.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
Several people have mentioned the possible use of a nuanced S-meter or a dBm or dBuV readout as a potential serious piece of test equipment (as opposed to the quick-glance uses that I have mentioned). In general I think receivers in the past have been unsuitable for such use because of temperature dependencies and other changes over time. Perhaps the K3, relying less on analog amplifiers, has a better potential for such use. If that is the case, it would really be a shame if that potential were not to be realized. Erik K7TV Well said Craig! I -- View this message in context: http://n2.nabble.com/Bigger-K3-S-meter-tp1399030p1438691.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
Well said Craig! I would again mention how useful a nuanced S-meter is for peaking a beam heading. I am not in the habit of looking up stations on QRZ when I work them or hear them (even though I have a fast PC with dual displays right at the operating position), so unless they have a dx prefix I really don't know the proper beam heading. Typically with normal qsb I can get close enough by swinging the beam past the desired direction a few times, IF I have a nuanced and easy to read S-meter. Also, a nuanced S-meter is an invaluable sensory input that gives us subtle clues as to what is happening with propagation, and we all want to have a better sense of that, I believe. Erik K7TV Craig-89 wrote: > > > Hi Guy > > It seems that the consensus is that a pretty innacurate S-meter is ok. > > I dont know why everything related to ham radio has to be reduced to the > bare minimum or be in the totally useless category. Not everyone's ham > radio life revolves around giving out cookie cutter signal reports. > > Most people would not buy any piece of test equipment with 300% > inaccuracy. I could just imagine all the shouting if power meters had a > tolerance of +- 200% or likewise VSWR meter. S meters should be no > different. > > A calibrated S meter could be useful tool in many other ways. > > - Measuring field strength and patterns of antennas. > > - Reporting on things like BPL and other radiated and conducted > measurements that seem to be a daily threat on HF. Just knowing they close > to S9 plus plus minus 20 db is not a professional way to build an > argument against such pollution in professional circles. Having a > calibrated S meter and adding something a like calibrated loop with a > known antenna factor would make collecting and surveying potential RF > pollution data very easy. While we don't need 0.1 db accuracy 1 db of > accuracy is easily achieved in SDR radios. > > http://www.vk1od.net/bpl/QueanbeyanBplTrial2.htm > > - Using a good S-meter would also be a reliable way of surveying a > potential new QTH. The data could be used to compare signal noise levels > to the thermal noise floor, or even compare what you are measuring to the > surveyed ITU noise levels on HF. It would be nice knowing that your > potential new QTH is in a QRM silent location. It would also be good > comparing noise floors amongst hams for various locations. > > - It would also be useful knowing how accurate and reliable propagation > programs are on a daily basis since they do predict signal levels. This > might come in handy if one wanted to build a DSP based DF system which > relies on ionospheric data. > > - As a general level meter around the shack, it could even be used as an > accurate power meter. > > So to me a well calibrated S-meter can take the place of many expensive > instruments that most hams dont have access to on a daily basis. It is a > very useful tool. When we use some sort of absolute reference our > understanding of what we are measuring on a daily basis increases our > understanding of what we are doing in our hobby. > > While we on this subject if further work is carried out on the K3's > s-meter you might as well follow the IARU's recommendation for S-meters > and make it quasi peak in nature. > > Besides these days, with the competition increasing in the new radio > market with radios like the Perseus, ADAT and the newly released cheap > Flexradio models, all which offer a very accurate S-meters as a feature. > It would do no harm to the K3's reputation having a feature that some > consider desirable, that's marketing not rocket science. > > > 73 > Craig > > --- On Fri, 10/31/08, Guy, K2AV <[EMAIL PROTECTED]> wrote: > >> From: Guy, K2AV <[EMAIL PROTECTED]> >> Subject: Re: [Elecraft] Bigger K3 S-meter >> To: elecraft@mailman.qth.net >> Date: Friday, October 31, 2008, 12:05 PM >> I would just like to see signal strength, including noise, >> in absolute >> reference levels. In particular when listening to a local >> while turning a >> beam kind of thing. Although that can be done relatively >> with the audio >> voltage level, it wouldn't allow me to tell a local >> that his ground wave >> signal has gone down 3 db and is staying there, or be able >> to create data >> for studies over time. >> >> Since it is an SDW, such is possible. dBuv is fine. Might >> need linearity >> points as part of the package which could be calibrated >> with a precision >> attenuator. >> >> >> Changing the functionality of the BG or SM commands so they >> could provi
Re: [Elecraft] Bigger K3 S-meter
Julian, I tend to use S-meters more for purposes other than for giving signal reports, but when I do give a signal report I prefer to make it an honest one and update it later in the qso. When I get a non-real report of 599 e.g. from a dx, it kind of neutralizes the joy of having made the contact. I think Elecraft and TT (and in the past Collins) deserve credit for providing meaningful S-meter scales. I think the biggest problem today with the existing S-meter standard is that the same standard is applied to each HF/MF band, with an abrupt change for VHF. A separate S9 definition for each band would make more sense because of different average noise levels. Sometimes in the past I have gone by the standard for 40 and down, and deliberately inflated the readings on the higher bands by switching on the preamp consistently for those bands. Of course if one uses a separate receive antenna, one may need to adjust reports for that. Given all possible adjustments, one might want to be able to set a dB offset individually for each band, and I am sure that the K3 could do that, although I would not push for it as a priority. Anyway, since you do external software for the K3, can you confirm that an S-meter displayed on the PC could get signal strength data from the K3 that has a fine enough granularity to show a change of 1 or 2 dB? Thanks, Erik K7TV Julian, G4ILO wrote: > > > > K7TV wrote: >> >> Are you referring to the K3's ability to display audio output level in mV >> or "dbV"? >> While mere signal reports can reasonably be given by ear, I have >> measurement in my blood and really appreciate that K3 capability. >> > I think signal reports are more politics or psychology than science. If > someone gives me 599 it's only good manners to send 599 back. It's just > the way I was brought up. :) If they send something other than 599 then I > realise that they are actually giving me a real report, so I try to give > them a real one back. But since signals can often vary from S7 to S9+20 > over the period of a QSO I think the idea of giving realistic signal > reports is actually unachievable anyway. > -- View this message in context: http://n2.nabble.com/Bigger-K3-S-meter-tp1399030p1400685.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
Are you referring to the K3's ability to display audio output level in mV or "dbV"? While mere signal reports can reasonably be given by ear, I have measurement in my blood and really appreciate that K3 capability. When I am not in a hurry, it is good for something like looking at filter response. However, it works best with the AGC turned off, which is a bit of a pain, and if I am peaking something I want to see analog movement, not numbers! That said, if the K3 were to acquire a capability to display RF input signal strength as a number, that would surely be very useful for something. If a program on a computer is the only way to see an S-meter showing small fluctuations of a dB or so, I might break down and finally install that program, which I assume is some kind of rig control program. After 45 years of hamming and being a computer engineer and just a casual contester, I have never wanted rig control by computer. PC's just aren't reliable enough, especially with Windows. Oh well, I will probably have to cave in soon just to get a panoramic display... Erik K7TV Guy, K2AV wrote: > > Wasn't there a way or going to be a way to display or send absolute dBm > for signal strength. That could just be a program running and getting > reports from the K3 over the serial port. Integer dBm would tell you > everything you needed to know. > > 73, Guy. > -- View this message in context: http://n2.nabble.com/Bigger-K3-S-meter-tp1399030p1400417.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Bigger K3 S-meter
I find the K3 S-meter a wonderful contrast to those other rigs I have had where I had to mentally compensate for the terrible non-linearity (in dB), i.e. S9=S9, S8=S8, S7=S7, S5=S6, S1=S5 and nothing below the real S5 even moves the meter. I haven't even begun to play with the AGC settings in the K3, but all the recent firmware releases seem to provide good S-meter readings without this mental translation. That said, I have run into a situation where I actually miss the meter on the old 1000D. That is when I try to turn the beam for maximum signal strength on a station I don't know the location of. As far as I can see, the K3 displays signal strength only in whole S-units, whereas I would find it useful to see changes smaller than that. I even miss the wildly exaggerated meter swings that you get in the lower part of the scale on a typical bad S-meter; they are just easier to see at a glance. Perhaps it would be useful to have a firmware option to just expand the K3 S-meter to something like 1 or 2 dB per tick on the scale. Of course I would have to use the RF gain control to bring the reading into the smaller range of the expanded scale, and then restore the normal S-meter scale for giving reports. Maybe I could achieve this expanded S-meter scale through an alternative AGC setting, available at the touch of a button? 73, Erik K7TV Ron D'Eau Claire wrote: > > And very few S-meters worked at all in CW mode since the BFO wasn't > isolated > from the AGC, so the AGC (and so the S-meter) was Off. > > Over the years contesters have brought some sanity to the S-number: ignore > the meter and send "5NN". > > The audio output voltage and dB comparison measurement displays available > on > the K3 are far superior to an "S-meter" for serious signal strength > measurements and comparisons. > > Ron AC7AC > > > > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] > Sent: Thursday, October 30, 2008 11:30 AM > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] Bigger K3 S-meter > > > I'm not sure that I understand the fascination of larger S meters, I > totally ignore mine. But back in the days of my ill spent youth, when > radios glowed in the dark, I owned a Hallicrafters SX-96 which had > an S meter that must have occupied at least a quarter of the front > panel, and went to "80 db over 9" if my memory serves me well. > Man could you give great signal reports.."ur 70 db over 9 but > pls agn ur name" and S-9 meant that the other station was audible. > > Doug > W6JD > > > ___ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > 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 > -- View this message in context: http://n2.nabble.com/Bigger-K3-S-meter-tp1399030p1400272.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] T1 How to mount it?
My T1 is sitting unused, along with my FT-817. The reason is that I haven't figured out the best way to mount them together. I am not looking for a fancy compact package, and it seems too messy to put the tuner into the radio's battery compartment (which I don't use for anything). My basic requirement is to have everything solidly connected together. I have had enough of radio connected to tuner connected to this and that, all draped over a rock, so that if one box starts sliding down, the rest follows... Fellow KX1 users will understand... Just mounting everything on a strip of plywood would do it. The strip would be narrow enough to stuff down through the top opening of a backpack, with the radio front panel at one end. Maybe that end would be supported by a hinged board to lift the front up during operation (with some kind of snap lock). The T1 could then be mounted facing the operator, under the radio. Of course, I would still just take the KX1 many times, but with conditions improving and higher bands coming to life, even supporting SSB at low power, the 817 will have its place. At least until there is a KX2... I wish the T1 had some kind of provision for mounting. I have thought of a foam pad with double-sided adhesive, but that seems messy when it comes time to change the battery. One could permanently glue on a plastic plate with a dovetail mount or ears for screw mounting. One could machine a replacement case back with the ears or dovetail incorporated. One could fabricate some kind of clamp. If you have implemented a solution, please let me know, even if it is just rubber bands! Maybe others would be interested too? 73 Erik K7TV -- View this message in context: http://n2.nabble.com/T1--How-to-mount-it--tp1347998p1347998.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K3 #1837 (kit) is alive
Assembly was uneventful. All standard tests passed, 10W yesterday and 100W today. Thanks Elecraft! Erik K7TV -- View this message in context: http://n2.nabble.com/K3--1837-%28kit%29-is-alive-tp1331867p1331867.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 Harmonic Distortion
Julian, G4ILO wrote: >I think it was me who used the term "ghost" signals when referring to the harmonically related CW traces >I could see on the CW Skimmer display. Julian, About 6 months ago I found a similar situation with another radio and another program. In that case the distortion was definitely caused by the sound card input being overdriven, not by the radio. I am not saying that that is happening for you, only that it CAN happen with certain equipment. Here are the details if you want to know. I was building a new interface that lets me operate PSK-31 and other modes (including pactor 2) with switching between any of two radios and any two hardware modems and soundcard. It is also designed to work with both my desktop computer and my laptop (HP ZT-3000) by manually moving the cable. Serial port was switched along with the modems. The radios were FT-1000D and TS-570, both interfaced through the connector on the back. The 1000D (now sold to finance K3) has a single fixed output level, the 570 three selectable levels. I selected the level most closely matching the 1000D. The software was MixW running on the HP laptop. I found that I could not only see a give station in two places, but copy their PSK-31 in both places! The second frequency was outside (above) the filter cutoff, but the signal was about as strong as the one in the passband. I don't remember the actual frequencies, but there was a big difference in them, such as double or triple. I didn't determine if the ghost was created as a harmonic or by mixing, but it was good copy and strong. (Hmmm,... wonder if PSK would be copiable on a harmonic?) My interface has a volume control for the output (as well as input) of each radio. When I turned down the output at the interface (not touching the radio), the ghost went away. On a tangent topic: I had previously run the 570 with the laptop using a much simpler interface, and somewhat marginal results (did not run into any ghost, was probably using a lower output level selected on the radio). That interface had short audio cables. The new interface has long cables for flexibility in placing the equipment around the shack. When I first tried to transmit, there was a horrible hum on the signal. I had tied together the 3 grounds of the 570 at the aux connector. I solved the problem completely by running separate 3 grounds from the 570 to the interface box with its transformers. The 1000D had no such need, maybe because its PSU was built-in) but I implemented both radio cables with separate grounds to be prepared for future radios. I should be covered for the K3, whether it behaves like a 1000D or like a 570. I wonder though if the K3 is more similar to one or the other in its grounding scheme... 73, Erik K7TV KX-1 T-1 K3 on order -- View this message in context: http://n2.nabble.com/K3-Harmonic-Distortion-tp797780p832903.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
When the hardware AGC responds under these conditions, I am guessing that the effect might be an increase in the general background noise heard. This is really what I was after. After looking at the clock last night and finishing off my post too quickly, I got poster's remorse about the last sentence. Of course, if the hardware agc works perfectly, I would expect the general effect to be a decrease in noise. Behind my sentence were two muddled thoughts: 1. If the agc hang or decay is very short, the random peaks in composite signal might cause very rapid sequences of normal/desensed noise, and this staccato effect might be perceived as an addition in noise although not increasing noise amplitude, and 2. This being a new radio design, it would not be inconceivable if some aspect of the agc design were flawed, resulting in actual increases in noise amplitude when the hardware agc kicks in repeatedly at a high rate. I received one response, off-list, that was aimed at this part of my post. The gentleman provided a great deal of insight into what might go wrong with the agc action and the second mixer. Those details went far beyond my thoughts. Unfortunately he did not actually have a K3, so there was no test data. I guess I had better be patient and wait until my K3 arrives! It should be easy to study the hardware agc action by using an external preamp to bring up the average signal level on a crowded band. I might hang one scope channel on the 8 MHz signal after the filter, and another channel on the hardware agc voltage, while listening to the radio. Of course, since noone on the list is obsessing about this aspect of K3 behavior, it will probably turn out to be unimportant to the overall performance of the radio. -- View this message in context: http://n2.nabble.com/Hearing-the-effect-of-narrower-roofing-filter-tp470635p795880.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
But if you leave the setting at its nominal, can you hear the difference as that bandwidth is selected? I'm not sure I understand the advantage you are gaining by bringing the crystal filter in later; I'll do if there's something to be gained, it sounds an interesting approach. David G3UNA David, Say that you have a 500 Hz (nominal) roofing filter with an (actual) 6-dB bandwidth of 550 Hz. When you choose the widest DSP bandwidth at which this roofing filter kicks in, here is what I think about the choices you have: 1. You have it kick in at 550 Hz DSP because it matches the DSP bandwidth. This may create the steepest slopes, but I would avoid it for digital modes since I would expect the group delays to vary near the flanks of the xtal filter, but not near the flanks of the (FIR) DSP filter. 2. You have it kick in at 500 Hz DSP because it is a "500 Hz filter". This logic makes no sense, since the xtal filter is actually 550 Hz. 3. You have it kick in at 500 Hz or less DSP because you want the DSP to cut away the group-delay-varying portion of the xtal filter passband. This would make sense. How much of the xtal filter response would of course depend on the group delay characteristics of the particular xtal filter. Of course if you don't use digital modes, you may want to go with approach #1. 4. You have it kick in at 600 Hz or above. Someone on the list suggested that this approach made the receiver sound more pleasant. The effect would essentially be to disable the DSP for receive purposes, except for the DSP's big improvement in ultimate rejection, and any bandwidth-unrelated DSP function that may be enabled. I have yet to hear for myself, but operating this way makes little sense to me unless there is something wrong with the DSP release. As to my original question, it seems that most respondents like to vary the DSP bandwidth as a means of switching the narrow xtal filter in and out, and to do this without lots of strong closeby signals. If the xtal filter kicks in according to #1 above, the composite bandwith of the two 550-Hz filters will be much less than 550 Hz. This will of course create an exaggerated effect of reducing the noise you hear, and here is an obvious risk of giving the narrow xtal filter way too much credit. If instead the kick-in point is set according to #3, you would reduce the effect of cascading on the overall bandwidth, and results would be more meaningful. However, as has been pointed out, it would be necessary to carefully adjust the gain for the xtal filter. Also, you would have to somehow work around the variations in effective DSP bandwidth step size, which have been stated to differ from the expected 50 Hz steps (at every 200 Hz?). Anyway, what I really wanted to know was NOT how the filters sound with just background hiss or average signals on the band. The justification for the narrow roofing filter would exist only if very strong interfering signal levels get through the standard roofing filter. I am thinking CW, and in case there is only one such signal, the AGC pumping would be easy to recognize. My understanding is that with current production K3's this would happen for an interfering signal level of somewhere around 25 to 30 dB over S9. In my mind, the interesting question is the case where there are multiple interfering signals within the roofing filter passband, including qrn etc. Even though these would not add up coherently, the peak voltage would grow with the number of signals, such that the ADC overload level would be reached without any individual signal reaching the 25 or 30 dB over S9. This suggests that the hardware AGC ideally should have an extremely fast attack time, and I assume that it does. When the hardware AGC responds under these conditions, I am guessing that the effect might be an increase in the general background noise heard. This is really what I was after. -- View this message in context: http://n2.nabble.com/Hearing-the-effect-of-narrower-roofing-filter-tp470635p795233.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Re: [Elecraft] K3 6m pre-amp
Try Antique Electronic Supply (www.tubesandmore.com). Their 2.5 mH is good for 160 mA, made by Hammond, core material is ferrite, 3 pi-windings, diameter 0.469", price $3.95. Erik K7TV >Another used-to-be-common part is a 2.5 mH RF choke, pi wound on a >ceramic form. After a lengthy search, I found Hammond still makes these, >only to learn that they were discontinued earlier this year. I managed >to get one (at a price of $14) and it's good that I only needed one to >use as a comparison reference for a QEX article I'm working on. -- View this message in context: http://n2.nabble.com/K3-External-2nd-receiver-with-KXV3-and-6m-pre-amp--tp587908p661341.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Fw: Elecraft Antennas in trees
FWIW I'd like to relate what I saw at the recent Field Day. The antenna crew used an air gun, similar, I think, to the ones used with tennis balls, but the projectile was a small cylinder about 1" in diameter and length, probably metal. The air reservoir was charged using a pump designed to inflate tires. A valve seemingly designed for lawn sprinkler systems was used with an electrical circuit to release the air charge into the pvc pipe barrel. The shooter did not aim for a specific branch but at a very steep angle over the top of the tree. This system had no problem getting the projectile way above the tops of tall pine trees. Due to the steep shooting angle, the projectile with fishing line also came down steeply on the other side (good idea if there is a building that you don't want to hit!). At this point the line was on top of several branches, big and small. The shooter would slowly pull the line back, directed by a second person with the projectile in view. This way several small branches were cleared without snagging the projectile. When the projectile was hanging down from a sturdy branch, the line was released to get it down to the ground. Erik K7TV -- View this message in context: http://n2.nabble.com/Fw%3A-Elecraft-Antennas-in-trees-tp585817p585869.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Question - for Educational Purposes
This discussion brings back memories of when I worked on FIR filter design many years ago, and I would add the following to the simple aspects that can be understood without math. The digital signal is of course a string of numbers representing samples from the analog waveform, just like the numbers coming off a music CD. The FIR filter works on some number N of the latest signal samples and uses all these N numbers to compute one output number. Then the oldest remembered number is dumped, and a new sample is entered, and the process repeats. Suppose there is a step change in the input samples. This will not reach its full impact on the output until the new sample level has propagated into all of the memorized samples that are used to compute the output. The FIR filter has a delay which is roughly the number N times the sample interval. However, it doesn't remember anything beyond this time span, as nothing except the past N samples can affect each output value. Now, suppose we change the computation of output samples so that this rule is broken. Just as an example, say that we use the N latest inputs as before, but also take the previous OUTPUT value into account when we compute the next output value. Now, that previous OUTPUT value is affected by at least one older input value, so the new output value is affected by more than N input values. This effect compounds, so that every output value theoretically is affected by all old input values. Thus an Impulse on the input keeps on infinitely affecting the output (theoretically). Hence "Infinite Impulse Response". The flanks of a FIR bandpass filter get steeper with increasing number N of input samples used in the calculation of each output. This results in increasing delay. We just don't hear the other station immediately. Obviously there is a tradeoff between delay and selectivity. The other day a list member posted carefully measured selectivity curves of the K3 with various DSP filter widths and roofing filters (along with similar measurements on 1000MP). I just glanced over the graphs, but to me it looked like the K3 DSP filter flanks were far from "brick wall" in terms of shape factor; off the top of my head, the crystal filters may have been sharper than the DSP in terms of skirt falloff for a given bandwidth setting. This brings new light on the debate as to whether you really need those extra roofing filters. I am sure that the K3 designers made an intelligent decision as to the tradeoff between DSP passband shape and DSP delay. Does anyone know the number of N for the current FIR filters? I assume that the sampling frequency would be about 30 kHz for the 15 kHz IF frequency. Erik K7TV >The infinite response of the IIR filter is usually not, in and of >itself, a problem. Even an FIR filter has to have a long "tail" >(ringing) in order to get a good shape factor. An FIR and IIR filter of >the same bandwidth and shape factor will tend to have similar ringing >characteristics out to the point where the FIR filter's ringing ends >(and the IIR filter's ringing continues). But the ringing is often >inaudible by that time anyway. > >Al N1AL -- View this message in context: http://n2.nabble.com/Question---for-Educational-Purposes-tp580366p580996.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 audio output v headphone sensitiviy
What is adequate headphone sensitivity may be highly dependent on operating mode and rig selectivity. Case in point: Many years ago I ordered an FT-1000 and a Heil headset (forget which model). Headset volume was fine for voice, and for CW using a wide filter. But the FT-1000, like the K3, can be set to very narrow CW filtering. This brings down the noise to far below what you have at more "normal" bandwidth. On a quiet band one can then work CW stations that are extremely weak. In my case, that is where the Heil headset became unuseable, because of inadequate volume. In my opinion, when trying to copy the weakest possible CW signal for a given bandwidth, the gain needs to be high enough that the noise level is quite loud. I sent the Heil headset back to the store. This episode begs the question: The K3 being famous for its "quiet" receiver, does it have enough rx audio gain to provide a loud background noise level in CW mode using the 50 Hz bandwidth, for an average speaker or for a reasonable headset (not Heil!)? Bill W4ZV wrote: > > > > David Yarnes wrote: >> >> I'll add my displeasure as well with regard to Heil >> headphones. I have 3 Heil headsets--the BM-10, the Heil >> Pro-Set Plus, and the Elecraft Pro-Set (made by Heil). In >> all cases the headphones suck! At least as far as output >> goes. >> > > I wonder if some of you may be going deaf? I have a Heil BM-10 that I've > had for ~30 year and two Heil Pro-Sets that I've had for ~20 years. I > just checked using my XG1 at 50 uV, AGC-Fast and RF Gain Max. I have > plenty of audio on both Pro-Sets with AF gain at ~10 o'clock. The BM-10 > is slightly better at 9:30 o'clock. For comparison, my current favorite > Extreme Isolation EX-29 is at ~9 o'clock. > > I have no complaints about the Heils but now prefer the EX-29, mainly > because its external noise isolation is far superior (and also much better > than any active noise reduction headphones). > > 73, Bill > > -- View this message in context: http://n2.nabble.com/K3---1037-in-IARU--contest-tp525033p527505.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
