[Elecraft] Possible doublet configuration
Hello All, Following this thread with much interest. I need a stealth antena and a doublet may do the job. Could I feed my K3/100 with ATU into a BL2 right at the antenna connector, the output of the BL2 to home made ladder line, (2 to 4 inch spacing) to a doublet approx 1/2 wavelength on the lowest freq? Is it OK to bring ladder line into the shack? The 1:1 or 4:1 of the BL2 might provide matching options in difficult cases. Thanks for any thoughts, Glen VK1FB __ 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] The use of a doublet
Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with balanced feeders and antennas, though one side is bound to have more capacitance to earth than the other, so balanced is fairly relative. David G3UNA __ 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 Diversity Rocks!
Don't forget the I.C.E #196 product. This has stopped my COR activity, and also isolates my MFJ-1026 noise antenna. And this is with the main antenna starting at the tuner in the shack, and the 2nd receive antenna a floor to ceiling vertical wire right next to the operating desk. Wayne WA9VEE Vic K2VCO wrote: Brett Howard wrote: So if we heard those relays switching then we're dangerously close to damage occurring? We found that we'd be listening and usually right in the middle of a guy giving his call you'd hear a click and a short bit of muting in the RX... Looks like swapping out for the AUX RF input isn't going to help me in that department. Perhaps I'll get greater isolation between the two receivers in that configuration though. I don't really know what caused my problem. So I am saving my speculations for the next time I feel I can take up Wayne's time. I do know that replacing the relay was a minor pain in the butt and I don't want to take any more chances. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html -- View this message in context: http://n2.nabble.com/K3-Diversity-Rocks%21-tp3252406p3262262.html Sent from the Elecraft mailing list archive at Nabble.com. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] vfo A B set up
My new, May 09, sn3012, K-3 works just fine. The following is how I would like to set up vfo A B, and so far I have been unable to do it my way. Either it is not possible, or I am just missing something in the manual which at age 70 is more than likely the problem. 1. Set up a 20 meter freq. in vfo A, (main) using ant #1. 2. Set up a 6 meter freq. in vfo B ( sub) using ant #2. If this is possible, than what I want to be able to do is work 20 mtrs,vfo A, ant #1, and listen on 6 mtrs using the 6 mtr ant #2, not on the 20 mtr ant on vfo A. Also when working 6 mtrs on ant #2, I want to be able monitor 20 mtrs on ant #1. If this is possible, any help would be appreciated. One could answer here of course, or direct to johncampbel...@brown-campbell.com. My cell is 248-895-5085 just in case someone wants to call with info. __ 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] Possible doublet configuration
Glen, Yes, you can certainly do that, and it should be quite efficient. You can bring open wire feeders or ladder line into the shack - the old timers did that all the time. The greatest problem is making the conductive path through the wall/window or other part of the structure. Replacing a piece of glass with plastic is often done, or with double hung windows, put a plastic panel beneath the lower sash and close the window on it. Don't forget to leave a drip loop at the point just outside, otherwise rain will drip into the dwelling. Like any other, the feedline length will act as an impedance transformer (a tuner does the same thing with lumped components) - so the matching range required may be quite large for some feedline lengths. The switchable balun may help with that, but try to stay away from feedline lengths that produce a very low or very high impedances in the shack because the balun can become ineffective at impedances far removed from its nominal 50 ohm or 200 ohm design points. I will not give any specific antenna lengths and feedline lengths, but you can experiment with either the real antenna or do some work with the TLW software (download from ARRL website) to tell you what lengths will work for you. 73, Don W3FPR Glen Torr wrote: Hello All, Following this thread with much interest. I need a stealth antena and a doublet may do the job. Could I feed my K3/100 with ATU into a BL2 right at the antenna connector, the output of the BL2 to home made ladder line, (2 to 4 inch spacing) to a doublet approx 1/2 wavelength on the lowest freq? Is it OK to bring ladder line into the shack? The 1:1 or 4:1 of the BL2 might provide matching options in difficult cases. Thanks for any thoughts, Glen VK1FB __ 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] Possible doublet configuration
Could I feed my K3/100 with ATU into a BL2 right at the antenna connector, the output of the BL2 to home made ladder line, (2 to 4 inch spacing) to a doublet approx 1/2 wavelength on the lowest freq? Is it OK to bring ladder line into the shack? This might work, but I think you will be better served with a few modifications. First of all, stay away from 1/2 WL on the lowest freq band, as higher bands will be harmonically related and can give you difficult to match impedances. I use 105 ft for my 80 thru 10 contest antenna. Secondly, stick with the published ideal feedline lengths and impedances, for example 30 ft of 300 ohm line for the 105 ft doublet. Ladder line can be brought inside, but coax is MUCH more user-friendly and can avoid lots of problems. Keep it as short as possible. Here, I use 6 ft of RG-213 to go from the K3 to the window termination with the ladder line. I've tried the BL2, and it worked OK most of the time but sometimes got quite warm - not a good sign. Instead I made a choke balun consisting of 4 turns of LMR-240 wound on two of the Fair-Rite type 31 big clamp-on ferrites (Mouser PN 623-0431177081). This unit works GREAT based on both impedance measurements and my actual experience. It sits right in the window opening and interfaces the ladder line with the RG-213. The K3 internal tuner works just fine with this setup on 80, 40, 20, 15 and 10. Haven't really tried the WARC bands. 73Craig AC0DS __ 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] The use of a doublet
That should be VK5BR Lloyd Butler http://users.tpg.com.au/users/ldbutler/SingleCoilZMatch.htm David G3UNA d.cut...@ntlworld.com wrote: Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with balanced feeders and antennas, though one side is bound to have more capacitance to earth than the other, so balanced is fairly relative. David G3UNA __ 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] The use of a doublet
For years I've used a a Z-match tuner I built using very husky components - big transmitting variables, salvaged 3 diameter silver plated tank coil and a 9:1 gear reduction drive for the main tuning cap. It works very well tuning a doublet fed with 450 ohm window line -- but even with the 9:1 reduction tuning can be very sharp. It's also more sensitive to slight variations caused by antenna movement etc. since you're tuning for near resonance. Those may be reasons it wasn't commercialised (much). In comparison, the Palstar BT1500A balanced L tuner I acquired a while back is less fussy - tuning isn't nearly as fast or critical. It also has the virtue of highly repeatable settings - it's quicker and easier to hop from band to band. Bob NW8L On Wed, Jul 15, 2009 at 3:44 AM, d.cut...@ntlworld.com wrote: Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with balanced feeders and antennas, though one side is bound to have more capacitance to earth than the other, so balanced is fairly relative. David G3UNA __ 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/Icom amp interface
Does anyone know of an interface between the K3 and an Icom 2KL/PW1 amps for auto band switching?Steve K4AHA __ 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 SCAN request
Is there any reason why SCAN could not be made to operate on the current paramters displayed in the VFOs? A lot of times I want to scan a range without storing it in a memory location. As it is now, in order to SCAN the current VFO settings you have to go through six steps: VM dial in a memory location VM MV MV SCAN Why not just SCAN alone? This would be a lot more agile. 73, Drew AF2Z __ 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] N2CQ QRP Contest Calendar: July 15 to Aug 17, 2009
~ N2CQ QRP CONTEST CALENDAR July 15 to Aug 17, 2009 ~ Summer FOX Hunt - QRP 20M CW... QRP Contest! EDT: Each Tue, 9 PM to 1029 PM UTC: Each Wed, 0100z to 0229z Info: http://www.qrpfoxhunt.org/ ~ NAQCC Straight Key/Bug Sprint *** QRP CONTEST! *** EDT: Jul 15, 8:30 PM to 10:30 PM UTC: Jul 16, 0030z to 0230z Rules: http://www.arm-tek.net/~yoel/contests.html ~ Digital Mode Club (DMC) Contest (RTTY) ... QRP Category Jul 18, 1200z to Jul 19, 1200z Rules: http://www.digital-modes-club.org/dmccontest.htm ~ North American QSO Party (RTTY) /QRP Entries Noted Jul 18, 1800Z to Jul 19, 0600Z Rules: http://www.ncjweb.com/naqprules.php ~ CQ WW VHF Contest (All, 6 2 Meters) ... QRP (10W) Category Jul 18, 1800z to Jul 19, 2100z Rules: http://www.cqww-vhf.com/ ~ RSGB Low Power Field Day (CW) ...QRP Contest! Jul 19, 0900z to 1200z Jul 19, 1300z to 1600z Rules: http://www.vhfcc.org/hfcc/rules/2009/rqrp.shtml ~ Colorado Gold Rush (20 mtr CW QRP) ... QRP Contest July 19, 2000z to 2159z Rules: http://www.cqc.org/contests/gold2009.htm ~ RUN FOR THE BACON (CW) *** QRP CONTEST *** EDT: Jul 19, 9 PM to 11 PM UTC: Jul 20, 0100z 0300z Rules: http://www.fpqrp.com/ ~ SKCC Sprint (Straight Key CW) ... QRP Awards Jul 22, z to 0200z Rules: http://www.skccgroup.com/sprint/sks/ ~ MQFD Monthly Sprint (CW/PH/Digital) *** QRP Contest *** Jul 25, 1800z to 2200z Rules: http://w2agn.net/mqfdsprint.html ~ Islands On The Air Contest (CW/SSB) ... QRP Category Jul 25, 1200z to Jul 26, 1200z Rules: http://www.vhfcc.org/hfcc/rules/2009/riota.shtml ~ Flight of the Bumblebees (CW) ... QRP Contest! EDT: Jul 26, 1300 to 1700 UTC: Jul 26, 1700z to 2100z Rules: http://adventure-radio.org/wiki/index.php?title=Main_Page ~ Summer FOX Hunt - QRP 20M CW... QRP Contest! EDT: Each Tue, 9 PM to 1029 PM UTC: Each Wed, 0100z to 0229z Info: http://www.qrpfoxhunt.org/ ~ Ten-Ten QSO Party (PH) ... QRP Category Aug 1, 0001z to Aug 2, 2359z Rules: http://www.ten-ten.org/Forms/QSOPartyRulesRevised.pdf ~ TARA Grid Dip Contest (PSK/RTTY) ... QRP Category Aug 1, z to 2400z Rules: http://www.n2ty.org/seasons/tara_grid_rules.html ~ EUROPEAN HF CHAMPIONSHIP (PH/CW) (EU work EU) Low Power Category Aug 1, 1200z to 2359z Rules: http://lea.hamradio.si/~scc/euhf/euhfcrules.htm ~ ARRL UHF Contest ... Low Power Category Aug 1, 1800z to Aug 2, 1800z Rules: http://www.arrl.org/contests/rules/2009/uhf.html ~ North American QSO Party (CW) ... 100W Max. (/QRP noted on entry) Aug 1, 1800z to Aug 2, 0600z Rules: http://www.ncjweb.com/naqprules.php ~ Adventure Radio Spartan Sprint (CW) *** QRP Event! *** Aug 4, 0100z to 0300z (First Monday 9 PM EDT) Info: http://adventure-radio.org/wiki/index.php?title=Spartan_Sprints ~ Worked All Europe DX Contest (CW) ... 100W category Aug 8, z to Aug 9, 2359z Rules: http://www.darc.de/referate/dx/xedcwr.htm ~ Maryland/DC QSO Party (SSB/CW) ... QRP Category Aug 8, 1600z to Aug 9, 0400z Aug 9, 1600z to Aug 9, 2359z Rules: http://www.w3cwc.org/2009rules.htm ~ SKCC Weekend Sprintathon (Straight Key CW) ... QRP Category Aug 9, z to 2359z Rules: http://www.skccgroup.com/sprint/wes/ ~ FPqrp - 10 Year Anniversary Contest (CW/SSB/Digital) ... QRP Aug 9, 0001 to Aug 15, 2359 Rules: http://qrpcontests.com/fpqrp/ ~ NAQCC Straight Key/Bug Sprint (CW) *** QRP Contest *** EDT: Aug 11, 8:30 PM to 10:30 PM UTC: Aug 12, 0030Z to 0230Z Rules: http://www.arm-tek.net/~yoel/contests.html ~ SARTG WW RTTY Contest ...
[Elecraft] K3 LED/LCD brightness
Is there any way to reduce the LED brightness when LCD Brt is set to dAY? It seems the LEDs default to an extremely bright state when the LCD backlight is turned off. 73, Drew AF2Z __ 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/Icom amp interface
I use the Microham Micro Keyer II to do this. Bob Serwy - N9RS -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Steve Cornell Sent: Wednesday, July 15, 2009 10:04 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3/Icom amp interface Does anyone know of an interface between the K3 and an Icom 2KL/PW1 amps for auto band switching?Steve K4AHA __ 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 Checked by AVG - www.avg.com Version: 8.5.387 / Virus Database: 270.13.14/2238 - Release Date: 07/15/09 06:07:00 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] The use of a doublet
Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with balanced feeders and antennas, though one side is bound to have more capacitance to earth than the other, so balanced is fairly relative. David G3UNA I believe it comes back to addressing the largest possible market with the simplest product, David. Relatively inexpensive Shunt-L T-network commercial tuners (e.g. MFJ) appeared in great quantity as no tune solid state transceivers became popular. These transceivers are really not no tune but, instead, are pre tuned for specific load impedance. The user is required to provide a pre tuned load that shows the proper impedance, indicated by a low SWR at the transmitter output. Unfortunately, many antennas in common use as the no-tune rigs came on the market - trap dipoles, multiple paralleled dipoles, trap verticals or, frequently, an end-fed random wires - provided the required match across the bands. The external tuner solved the problem, providing the low SWR the modern rigs required when feeding these antennas and able to handle an impedance range similar to the popular Pi-network used in older transmitter outputs that previously fed these antennas. In short, no tune rigs just moved the output tuning from the transmitter or transceiver itself to an external box: the antenna tuner. Although the Shunt-L, T-network can be very lossy, it can be very efficient too when used properly. The key is to adjust it for lowest Q where the circulating currents in the coil are lowest. Just like feed lines, With the Shunt-L T-network the lowest Q and lowest loss occur with the *least* inductance in the circuit that can provide a match to the rig. Again, keeping things simple to address the basic needs of the most customers, manufacturers like MFJ use an inexpensive switch-tapped inductor in their original tuners. The taps, inductance and capacitor ranges were established to provide a match from a few tens of ohms to 600 ohms or so. They'd match much wider ranges of impedances, but it was not unusual to discover that the tap settings weren't optimal. In some cases that led to situations where high circulating currents and losses occurred because the taps were too far apart. And of course, some tuners are used by Hams who have never carefully studied the manual that came with it, so they ended up using the wrong settings with the mistaken belief that all was well if the SWR on the link to the rig was low. Some years ago, Kevin Schmidt, W9CF, wrote a neat little Shunt-L T-Match tuner simulator in Java that's available to play with on line at many sites. One is here: http://fermi.la.asu.edu/w9cf/tuner/tuner.html You can download the program or run it on the WEB page, twirling the knobs with your mouse. It gives you the input/output impedances with the inductance and capacitance needed and the loss as a percentage of power and in dB for a given setting. I'm not sure what all the assumptions about conductor losses, etc., were for this simulator, but playing with it provides an intuitive feel for how the T-match works. I ignored one type of antenna that was quite popular about the time the no tune rigs appeared. That was the folded dipole. It was cheap and easy to make from 300 ohm twin-lead or home-made open wire line, avoiding the expense of coax for a very efficient and relatively broad band antenna, covering much if not all of the 80 meter band with a decently low SWR. But it needed a balanced feed. So MFJ and others provided a 4:1 toroidal balun in their tuners specifically to provide for these types of antennas (including the variant of the Windom fed with twin lead that was becoming popular too). Those baluns work well when feeding an impedance somewhere around 300 to 600 ohms, transforming it to about 50 or 100 ohms, right in the middle target range for the T-network to match most efficiently. Of course, many Hams immediately attached those baluns to their open-wire fed multiband doublets. That works fine where the antenna and feed line combine to provide a low impedance at the rig. Where the impedance is very high it doesn't. Again, the manuals with most Shunt-L T-network tuners I've seen say to avoid situations where the feed point impedance is high. MFJ, for example, goes so far as to give owners combinations of feed line lengths and antenna lengths to avoid with a doublet and cautions about using them with Windom antennas under certain situations to avoid these impedance extremes. That's why I have a wide-range link-coupled tuner for use with a doublet. That sort of
[Elecraft] Fw: Re: The use of a doublet
I count three coils in the single coil Z Match. Also there is a hard to find two section variable capacitor. One of the coild has two taps. This is probably the reason that it has not been used in commercial matching networks recently. Willis 'Cookie' Cooke K5EWJ --- On Wed, 7/15/09, d.cut...@ntlworld.com d.cut...@ntlworld.com wrote: From: d.cut...@ntlworld.com d.cut...@ntlworld.com Subject: Re: [Elecraft] The use of a doublet To: Ron D'Eau Claire r...@cobi.biz, 'Phil LaMarche' plama...@verizon.net, d.cut...@ntlworld.com, '.hank.' k...@inbox.com Cc: 'Elecraft_List' elecraft@mailman.qth.net Date: Wednesday, July 15, 2009, 7:17 AM That should be VK5BR Lloyd Butler http://users.tpg.com.au/users/ldbutler/SingleCoilZMatch.htm David G3UNA d.cut...@ntlworld.com wrote: Can anyone point to why the single coil Z match wasn't commercialised rather than the T match? (Perhaps it's a historical thing and manufacturers just copy each other, notwithstanding the Johnson Matchbox of course, which is no longer produced.) I'm in process of building one to cover 160 to 10 from VK2BR (?). I'm hoping that the link coupling will help with balanced feeders and antennas, though one side is bound to have more capacitance to earth than the other, so balanced is fairly relative. David G3UNA __ 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
[Elecraft] More on doublet and feedline issues
Prior to using the SGC auto-tuner at the end of the coax I used a home made balanced tuner. This was simply two 30uH tapped coils ( one for each side of the ladder line ) And then a variable cap switched in with a DPDT for either step-up or step-down config. As mentioned before, putting the tuner at the end of the coax helps to keep the coax usage for what it is designed for (unbalanced 50 ohms). This minimizes SWR losses on the coax and heat losses and saturation within a balun, which can in some cases eat up a percentage of the transmitters output power. This is especially critical in QRP usage. In order to find the taps for this I built a simple qrp tapped L-network. I used my MFJ antenna analyzer to find the correct combinations of L + C on the L-network for each band. Then divide the L between the two parallel coils and you have a balanced tuner. In this case: rig to coax to balun to balanced tuner to ladderline. Roy McCoy indicates that if one uses a tuner prior to the coax, one should use a Kwatt rated balun at the ladder line end of the coax to minimize flux saturation and possible toroid destruction. I use a Kwatt balun anyway. Just get the best in the first place and then I won't be fishing for it afterwords. Prior to this, I used a standard MFJ versa tuner sitting between the rig and coax, and there were always bands or band-segments that I could not operate in due to the inability to find a match. This is because every design has compromise built into it and as such, most T type tuners have just enough component reactance to meet AVERAGE matching requirements. And so, when your antenna system matching requirement exceeds average, your out of luck. This is especially true with auto tuners built into rigs. Meeting ROI (return on investment) demands requires minimizing matching capability. L.B. Cebik (http://www.cebik.com) was probably one of the most knowledgeable Hams I've ever had the privilege to correspond with, on the topic of feed-line lenghts. He is the first one to remind me of the (1/8 wL @ lowest operating Frq) rule for optimizing ladder-line length. Use plenty of antenna connector gum outside to prevent moisture from seeping into the coax, and keep all of the wire/connector points dry. -- bw...@fastmail.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 LED/LCD brightness
It appears to me that the LCDs have only one brightness, none! Only the back light has brightness. When set to DAY the back light is off and the contrast is just from the reflection on the back plane versus opaque for the activated elements. I didn't know there was a Day setting until your post even after a few thousand contacts over the past year. Willis 'Cookie' Cooke K5EWJ --- On Wed, 7/15/09, drewko drew...@verizon.net wrote: From: drewko drew...@verizon.net Subject: [Elecraft] K3 LED/LCD brightness To: Elecraft@mailman.qth.net Date: Wednesday, July 15, 2009, 8:47 AM Is there any way to reduce the LED brightness when LCD Brt is set to dAY? It seems the LEDs default to an extremely bright state when the LCD backlight is turned off. 73, Drew AF2Z __ 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 LED/LCD brightness
Cookie, The LEDs are the ones on the Shift, Width, etc. knobs; they become extremely bright when LCD Brt (display backlight) is set to dAY (or off), and there is no way to adjust them because LED Brt is no longer functional (it just beeps when you spin the vfo). Only when LCD Brt is set at some value 1 to 8 can LED Brt be adjusted. I checked the above text about five times for proper use of LED vs LCD... it can get a little confusing, hahah Anyhow, I'd like to use the LCD day setting and also be able to adjust the LED brightness down. 73, Drew AF2Z On Wed, 15 Jul 2009 09:58:49 -0700 (PDT), you wrote: It appears to me that the LCDs have only one brightness, none! Only the back light has brightness. When set to DAY the back light is off and the contrast is just from the reflection on the back plane versus opaque for the activated elements. I didn't know there was a Day setting until your post even after a few thousand contacts over the past year. Willis 'Cookie' Cooke K5EWJ __ 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 LED/LCD brightness
drewko wrote: Is there any way to reduce the LED brightness when LCD Brt is set to dAY? It seems the LEDs default to an extremely bright state when the LCD backlight is turned off. Interesting. The LED BRT setting seems to be disabled when LCD BRT is set to dAY. Perhaps that could be fixed (to allow a separate day-time LED BRT setting). Personally I find the LCD difficult to read in dAY mode anyway, but the glaring LEDs do make it even worse... ~Iain / N6ML __ 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 LED/LCD brightness
Actually, I sometimes like to use the day settings at night when I don't necessarily need to be watching at the display-- the LED brightness is way too bright then. It would be nice to be able to turn them down also. Funny thing... as much power is consumed when LCD Brt is set to dAY (backlight = off) as when it is set to max. I guess some of this is due to the extremely bright LEDs in the day settng. 73, Drew AF2Z On Wed, 15 Jul 2009 10:22:15 -0700, ~Iain / N6ML wrote: drewko wrote: Is there any way to reduce the LED brightness when LCD Brt is set to dAY? It seems the LEDs default to an extremely bright state when the LCD backlight is turned off. Interesting. The LED BRT setting seems to be disabled when LCD BRT is set to dAY. Perhaps that could be fixed (to allow a separate day-time LED BRT setting). Personally I find the LCD difficult to read in dAY mode anyway, but the glaring LEDs do make it even worse... ~Iain / N6ML __ 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 LED/LCD brightness
Now I see what you are talking about Drew. I never paid attention to these settings other than LCD Brightness and Back light Brightness. I am not sure what your reason for turning the back light off might be. If you are operating in sun light I don't think that you can see the back light on the LCD with a setting at 2 and the current drain is small enough that I don't detect it on my power supply ammeter. I have never tried to operate my K3 outdoors and I am simulating it by aiming my 75 watt desk lamp at the LCD, but that looks OK to me. Is that a possible work around for your? Willis 'Cookie' Cooke K5EWJ --- On Wed, 7/15/09, drewko drew...@verizon.net wrote: From: drewko drew...@verizon.net Subject: Re: [Elecraft] K3 LED/LCD brightness To: Elecraft@mailman.qth.net Date: Wednesday, July 15, 2009, 10:21 AM Cookie, The LEDs are the ones on the Shift, Width, etc. knobs; they become extremely bright when LCD Brt (display backlight) is set to dAY (or off), and there is no way to adjust them because LED Brt is no longer functional (it just beeps when you spin the vfo). Only when LCD Brt is set at some value 1 to 8 can LED Brt be adjusted. I checked the above text about five times for proper use of LED vs LCD... it can get a little confusing, hahah Anyhow, I'd like to use the LCD day setting and also be able to adjust the LED brightness down. 73, Drew AF2Z On Wed, 15 Jul 2009 09:58:49 -0700 (PDT), you wrote: It appears to me that the LCDs have only one brightness, none! Only the back light has brightness. When set to DAY the back light is off and the contrast is just from the reflection on the back plane versus opaque for the activated elements. I didn't know there was a Day setting until your post even after a few thousand contacts over the past year. Willis 'Cookie' Cooke K5EWJ __ 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] K1 led backlight setting
Is there a recommendation from you all as to which led brightness setting to use for K1 led backlight? It will be used primarily for hotel and field portable ops, thanks Eric WD6DBM Sent from my iPhone __ 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 serial 584 is now OK
In case anyone is wondering, my K3 is running tickety-boo now that the KIO3 board has been replaced (thanks to Gary Surrency for diagnosis and the rest of Elecraft service folks who got me the replacement board tout suite!). And, uh, the 80-meter only decrease in sensitivity was most decidedly NOT condx or a failure of anything in the K3 box but a failure of the wetware which operated the box -- somehow, I know not how, I was using the non-existent RX ANT. Ooops. 73, Joe, W2RBA __ 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/Icom amp interface
Does anyone know of an interface between the K3 and an Icom 2KL/PW1 amps for auto band switching? Your question has two answers: For the 2KL a BCD to 1 of 8 decoder can switch the necessary voltage dividers to create the analog (stepped voltage) band data signal needed to switch bands with the 2KL or 4KL. The W9XT BCD-10 is capable of providing the necessary switch to ground signals to easily drive a set of voltage dividers in this application. However, unlike most of the other Icom accessories, the PW-1 will not switch bands based on the analog (stepped voltage) signal and requires specific frequency data from the Icom CI-V transceive broadcast. . I know of only three devices in current production that will translate Elecraft (Kenwood) CAT data to the Icom CI-V format. They are: microHAM Station Master (PA control function), the microHAM microKEYER II (auxiliary CI-V output) and microHAM MK2R or MK2R+ (accessory serial function). The now discontinued microHAM Band Decoder is also capable of providing the CAT translation if you can find a used one. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Steve Cornell Sent: Wednesday, July 15, 2009 11:04 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3/Icom amp interface Does anyone know of an interface between the K3 and an Icom 2KL/PW1 amps for auto band switching?Steve K4AHA __ 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 LED/LCD brightness
Cookie, I can see the dAY display pretty well with my normal indoor operating position lighting, but the LEDs at this setting are irritatingly bright. Sometimes during the day I have the rig on, just scanning a band or listening to a SWBC station while I'm doing something else around the shack; don't really need the display on then anyway. The ma difference as shown on the K3 between LCD Brt 2 and dAY is about 70 ma. (No, I'm not a global warmist or anything... far from it. Just thought it was interesting...) 73, Drew AF2Z On Wed, 15 Jul 2009 10:48:30 -0700 (PDT), Willis 'Cookie' Cooke wrote: Now I see what you are talking about Drew. I never paid attention to these settings other than LCD Brightness and Back light Brightness. I am not sure what your reason for turning the back light off might be. If you are operating in sun light I don't think that you can see the back light on the LCD with a setting at 2 and the current drain is small enough that I don't detect it on my power supply ammeter. I have never tried to operate my K3 outdoors and I am simulating it by aiming my 75 watt desk lamp at the LCD, but that looks OK to me. Is that a possible work around for your? Willis 'Cookie' Cooke K5EWJ __ 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 LED/LCD brightness
You have a much more sensitive ammeter than I do Drew. I draw about an amp with the back light on 4 where I usually keep it, but I can;t see the difference if I change the setting to DAY. 70 ma at 13.8 V is only about 1 watt. My desk lamp has a 60 watt bulb so you would save more money to turn off some of the lights in your ham shack. Still, it should be possible to allow you to adjust the LEDs with a software change if the software gurus work it to the top of their priority list. Willis 'Cookie' Cooke K5EWJ --- On Wed, 7/15/09, drewko drew...@verizon.net wrote: From: drewko drew...@verizon.net Subject: Re: [Elecraft] K3 LED/LCD brightness To: Elecraft@mailman.qth.net Date: Wednesday, July 15, 2009, 11:26 AM Cookie, I can see the dAY display pretty well with my normal indoor operating position lighting, but the LEDs at this setting are irritatingly bright. Sometimes during the day I have the rig on, just scanning a band or listening to a SWBC station while I'm doing something else around the shack; don't really need the display on then anyway. The ma difference as shown on the K3 between LCD Brt 2 and dAY is about 70 ma. (No, I'm not a global warmist or anything... far from it. Just thought it was interesting...) 73, Drew AF2Z On Wed, 15 Jul 2009 10:48:30 -0700 (PDT), Willis 'Cookie' Cooke wrote: Now I see what you are talking about Drew. I never paid attention to these settings other than LCD Brightness and Back light Brightness. I am not sure what your reason for turning the back light off might be. If you are operating in sun light I don't think that you can see the back light on the LCD with a setting at 2 and the current drain is small enough that I don't detect it on my power supply ammeter. I have never tried to operate my K3 outdoors and I am simulating it by aiming my 75 watt desk lamp at the LCD, but that looks OK to me. Is that a possible work around for your? Willis 'Cookie' Cooke K5EWJ __ 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 LED/LCD brightness
Me either nor do I recycle but those LEDs being on when the display is off seems rather odd. No, I'm not a global warmist or anything... far from it. Steve N4LQ n...@carolina.rr.com - Original Message - From: drewko drew...@verizon.net To: Elecraft@mailman.qth.net Sent: Wednesday, July 15, 2009 2:26 PM Subject: Re: [Elecraft] K3 LED/LCD brightness Cookie, I can see the dAY display pretty well with my normal indoor operating position lighting, but the LEDs at this setting are irritatingly bright. Sometimes during the day I have the rig on, just scanning a band or listening to a SWBC station while I'm doing something else around the shack; don't really need the display on then anyway. The ma difference as shown on the K3 between LCD Brt 2 and dAY is about 70 ma. (No, I'm not a global warmist or anything... far from it. Just thought it was interesting...) 73, Drew AF2Z On Wed, 15 Jul 2009 10:48:30 -0700 (PDT), Willis 'Cookie' Cooke wrote: Now I see what you are talking about Drew. I never paid attention to these settings other than LCD Brightness and Back light Brightness. I am not sure what your reason for turning the back light off might be. If you are operating in sun light I don't think that you can see the back light on the LCD with a setting at 2 and the current drain is small enough that I don't detect it on my power supply ammeter. I have never tried to operate my K3 outdoors and I am simulating it by aiming my 75 watt desk lamp at the LCD, but that looks OK to me. Is that a possible work around for your? Willis 'Cookie' Cooke K5EWJ __ 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] K1 led backlight setting
Eric, If you are going to be using it in lighted areas and can stand the increased current drain, go for the brighter option. OTOH, the K1 display without the backlight is fine in lighted areas already, and the dim backlight is good for dark places, so just take your pick based on your particular desires. 73, Don W3FPR Eric wrote: Is there a recommendation from you all as to which led brightness setting to use for K1 led backlight? It will be used primarily for hotel and field portable ops, thanks Eric WD6DBM __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] The use of a doublet
I have long been an advocate of the center fed doublet. I have put them up in numerous state and even in Germany. Of course I have used different tuners. Folks here in this write about of all kinds of external tuners. May I make a radical suggestion? Use the internal K3 antenna tuner! Now I know that most transceivers have internal tuners that will operate well only up to 3:1 swr. The K3 tuner is rated much higher than that. Indeed, I was very surprised how well it works here in my station with my 135' foot dipole with 450 ohm ladder line and a balun. I highly recommend that one should consider the K3 tuner. It's a winner. Tom Brereton, W0TOM __ 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] The use of a doublet
I'm using a 66' doublet fed with homebrew ladder line for portable operations in my yard. I have it flat top up in a tree about 35' up. I made a small adapter to go from the ANT1 connector from my KAT3 to a couple of banana sockets. I then bring the ladder line straight into that adapter. I wound up with a feedline length of around 55' and the KAT3 tunes up on this arrangement 80m-10m FB. It is obviously very short for 80m and I don't use it on that band, but the KAT3 did tune up on it (I'm sure not very efficiently). I've been running 5 watts out there and worked a number of states. I worked Italy on 5 watts last summer on 20m. I hooked the doublet directly to the KAT3 at the urging of Ron (AC7AC) and Don (W3FPR) here on the list and have been very happy with it. 73, Dave W8FGU THOMAS BRERETON wrote: I have long been an advocate of the center fed doublet. I have put them up in numerous state and even in Germany. Of course I have used different tuners. Folks here in this write about of all kinds of external tuners. May I make a radical suggestion? Use the internal K3 antenna tuner! Now I know that most transceivers have internal tuners that will operate well only up to 3:1 swr. The K3 tuner is rated much higher than that. Indeed, I was very surprised how well it works here in my station with my 135' foot dipole with 450 ohm ladder line and a balun. I highly recommend that one should consider the K3 tuner. It's a winner. Tom Brereton, W0TOM __ 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] Possible doublet configuration
Following this thread with much interest. I need a stealth antena and
a doublet may do the job.
Could I feed my K3/100 with ATU into a BL2 right at the antenna
connector, the output of the BL2
to home made ladder line, (2 to 4 inch spacing) to a doublet approx
1/2 wavelength on the lowest
freq? [[snip]]
Sure you can do it that way, but the ATU may or may not tune it on all
bands - depends on that matching range of the ATU and the impedance of
the antenna system at each frequency. Impedance does change with
frequency, and as long as it stays within the matching range of the ATU,
it should work just fine. But I think you would have much greater
success with a non resonant length for the doublet - say an 88' doublet
for 10 thru 80 meter coverage, or a 44' doublet for 10 thru 40 meter
coverage. These lengths aren't carved in stone either, the theory is to
stay away from 1/2 wavelength per side of the doublet to avoid extremely
hig impedance. You might even want to look into an off center fed
doublet fed with balanced feedline with the balun at the end of the
balanced feedline and a short run of coax coming into the shack. The
idea behind the off center feed is that the impedance stays fairly close
to the same (around 200 to 300 ohms) over a wide frequency range and
allows a 4:1 balun to convert it down close to 50 to 75 ohms (or
thereabouts). Do a google search for the FD-3, or FD-4 antenna to get a
better idea of what I mean.
Is it OK to bring ladder line into the shack? [[snip]]
Sure ! Just keep it clear of long runs that are parallel to large metal
objects and it will work just fine.
73 - Rick McKee, KC8AON
Southern Ohio - EM88sn
www.angelfire.com/electronic2/qrp
With God all things are possible ~ ((' ~
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Re: [Elecraft] The use of a doublet
Tom (and all others who have commented), Please pass along the length and type of your feedline when making statements of the effectiveness and ease of tuning for your antenna. With a resonant halfwave dipole fed with coax (or any line matched to the antenna impedance), the feedline length is not important, but most multiband antennas are not like that and the feedline length is a very important parameter. The feedline is a part of the antenna system, and when not matched to the antenna feedpoint impedance, it will act as an impedance transformer. Your particular antenna and feedline may work just fine, but the same antenna with a different feedline length may not work out well. So for others to duplicate your experiences (or attempt to), please add the length and type of feedline. 73, Don W3FPR THOMAS BRERETON wrote: I have long been an advocate of the center fed doublet. I have put them up in numerous state and even in Germany. Of course I have used different tuners. Folks here in this write about of all kinds of external tuners. May I make a radical suggestion? Use the internal K3 antenna tuner! Now I know that most transceivers have internal tuners that will operate well only up to 3:1 swr. The K3 tuner is rated much higher than that. Indeed, I was very surprised how well it works here in my station with my 135' foot dipole with 450 ohm ladder line and a balun. I highly recommend that one should consider the K3 tuner. It's a winner. Tom Brereton, W0TOM __ 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 knob on K2?
Does the K3 knob fit on the K2? Just curious, seems like it'd be an easy alternative to the Yaesu knobs many of you are using... Tom W0EA __ 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] The use of a doublet
For those who might be a little mystified by this discussion of feedlines and antennas, I can recommend the series of articles titled Another Look at Reflections by M. Walter Maxwell (W2DU/W8HKK) published in QST between 1973 and 1976. The whole series is available as a single PDF file at http://www.arrl.org/members-only/tis/info/pdf/Reflect.pdf (for ARRL members only, sorry.) It's a very thorough treatment of the subject of transmission lines and impedance matching. Easy reading in some places and a bit tougher in others, it's well worth close and careful study if you want to understand transmission lines and matching. 73 -- Joe KB8AP On Jul 15, 2009, at 4:34 PM, Don Wilhelm wrote: ... The feedline is a part of the antenna system, and when not matched to the antenna feedpoint impedance, it will act as an impedance transformer. Your particular antenna and feedline may work just fine, but the same antenna with a different feedline length may not work out well. ... __ 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] K2/100 + KAT100-1 for sale
My friend John K7WP is selling his K2/100. I have aligned this radio and will vouch for it's excellent condition and performance. It includes the following: K2 KPA100 KSB2 K160RX K60XV KNB2 KDSP2 KAT100-1 At the current prices this is $1810 worth of kits. You get it all for $1200, assembled. In addition I added K3-style protection circuits to this K2 to prevent damage to the MCU from miss-connections at the microphone jack. Contact John directly at the email address below. 73 Gary, N7IR -Original Message- Behalf Of John Arthurs Sent: Wednesday, July 15, 2009 1:51 PM Subject: Stuff for sale pre-Williams Hi all.. Couple of things for sale here: 1. Elecraft K2/100 loaded with options, including the KAT100 antenna tuner, with manuals, and Mini-Manual by Nifty. This radio has been a regular with the VooDudes in Africa over the last several years, and primarily the 160m radio. Beautiful condition. All for $1200. 2. Bird 43 Wattmeter SN 162122 with 250w, and 5000w slugs. All for $185. I will be at the Williams, AZ Hamfest on Sat., and can deliver the goods there. Thanks, and 73! John K7WP arthursk...@aol.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
