Re: [Elecraft] wire for random wire antenna using kx3
Shortwave transmitters tend to live very long lives. Sent from my iPhone > On Dec 19, 2018, at 19:13, Phil Kane wrote: > >> On 12/19/2018 3:25 PM, W2xj wrote: >> >> must have been an old tx. The ones dating back around 60 years had >> front panel cranks and newer models did changes automatically. > > He actually had to go into the cage and change taps on coils. I don't > remember the age/model of the TX but it was in service in the early > 1980s as I remember it. > > 73 de K2ASP - Phil Kane > Elecraft K2/100 s/n 5402 > > From a Clearing in the Silicon Forest > Beaverton (Washington County) Oregon > __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/19/2018 3:25 PM, W2xj wrote: > must have been an old tx. The ones dating back around 60 years had > front panel cranks and newer models did changes automatically. He actually had to go into the cage and change taps on coils. I don't remember the age/model of the TX but it was in service in the early 1980s as I remember it. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
must have been an old tx. The ones dating back around 60 years had front panel cranks and newer models did changes automatically. Sent from my iPad > On Dec 19, 2018, at 2:40 PM, Phil Kane wrote: > >> On 12/18/2018 10:35 AM, W2xj wrote: >> >> I was referring to ham tuners but shortwave broadcast stations QSY >> with hundreds of kilowatts many times a day. > > And a former friend who was one of th station operators at KGEI (SW > station now defunct) had the record time for changing bands on the 100 > KW TX. Even though the 100 was off the air, the 250 KW was still on the > air on yet another band so rubber mats, grounding sticks, and gloves > were the order of the day. > > 73 de K2ASP - Phil Kane > Elecraft K2/100 s/n 5402 > > From a Clearing in the Silicon Forest > Beaverton (Washington County) Oregon > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
but phasors are not matching networks. theoretically they are 50 ohms in and 50 ohms out although in reality that is not quite the case. in any rate the high power sites i have built has the phasor at the highest power tower. at some sites i put the phasor in its own building at the center of the array. Sent from my iPad > On Dec 19, 2018, at 2:18 PM, Phil Kane wrote: > >> On 12/17/2018 7:45 PM, W2xj wrote: >> >> Coming from the broadcast side, especially AM broadcasting, I never >> considered resonance particularly important. Really it’s just the >> transmitter that cares. We always put matching at the antenna but in >> ham radio we usually have tuners at or in the TX. > > Ah, but the phaser (matching networks) for AM broadcast directional > arrays usually is located at or near the transmitter - or at least they > were when I dealt with AMers in the 1960s-1990s. > > 73 de K2ASP - Phil Kane > Elecraft K2/100 s/n 5402 > > From a Clearing in the Silicon Forest > Beaverton (Washington County) Oregon > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/18/2018 10:35 AM, W2xj wrote: > I was referring to ham tuners but shortwave broadcast stations QSY > with hundreds of kilowatts many times a day. And a former friend who was one of th station operators at KGEI (SW station now defunct) had the record time for changing bands on the 100 KW TX. Even though the 100 was off the air, the 250 KW was still on the air on yet another band so rubber mats, grounding sticks, and gloves were the order of the day. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/2018 7:45 PM, W2xj wrote: > Coming from the broadcast side, especially AM broadcasting, I never > considered resonance particularly important. Really it’s just the > transmitter that cares. We always put matching at the antenna but in > ham radio we usually have tuners at or in the TX. Ah, but the phaser (matching networks) for AM broadcast directional arrays usually is located at or near the transmitter - or at least they were when I dealt with AMers in the 1960s-1990s. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/2018 2:43 PM, W2xj wrote: > Remember this IS a hobby and to each their own. As an engineer, I do > model and design what I use. I hate the “by guess and by golly” > approach. Everything I do is carefully planned in advance and is a > part of my enjoyment of the hobby but YMMV. I too am an engineer, senior manager of a consulting engineering firm, but I separate my hobbies from my work. Keeps me sane. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/2018 11:03 AM, Fred Jensen wrote: > Larson E. Rapp is using an alias now? Haven't seen that author attribution for decades. Shows my age. :) 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
To be fair, solid state PAs are far less forgiving about match than were tubes. This is completely due to broadband design. This can be solved by including an ATU as is done with a number of Elecraft products either as an option or a feature. In the end it is about what it takes to keep the PA happy. Sent from my iPhone > On Dec 18, 2018, at 17:00, Fred Jensen wrote: > > Yep, the term was known when I became KN6DGW in 1953, but somehow no one > cared. Standing waves were sort of benign, you ran your transmission line > [often 300 ohm open-wire, or TV twinlead] to the 2 or 3 turn link and > adjusted it inwards until your TX was "loaded" to rated input power. > Standing waves formed the basis of "Lecher Lines" used to measure frequency > [well ... wavelength] generally for VHF and above. Standing waves just > didn't create the heartburn that they seem to today. Granted, today's TX are > comfortable with 50 ohms and not much else but that's just impedance matching > networks. > > 73, > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 12/18/2018 3:32 PM, Wes Stewart wrote: >> T. A. Gadwa, “Standing Waves on Transmission Lines”, QST, December 1942, pp. >> 17-21. >> >> Wes N7WS > > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Skip, That is "telling it like it was". If you want to go back to those "good old days", build yourself a link coupled tuner. It will likely use plug-in coils and perhaps a swinging link. Then you can tune it just like you did on your old transmitter/amplifier - except you do not have to "dip the plate" and change the link coupling to bring the plate current up to where you want. You adjust that tuner so you have a low SWR at the input. If you can't get a low SWR, adjust the transmission line taps on the coil and try again until you get it right. Each antenna requires different coil taps and different tuning. Tune up and band to band QSYs were not quick and easy in those days. Those who wanted instant band hopping had multiple amplifiers each with their dedicated antennas (rich hams) - now we can have that same capability with a single multiband antenna and an ATU. While I do have a couple of those tuners (with their wide spaced "bread slicer" capacitors) in my collections, I prefer to use the newer ATUs - push a button and it finds a match. The old methods are not better or worse, but just different. Newer stuff does it easier - but it is interesting to know what is happening in the stuff that does the impedance transformation. Engineers know the concepts, and older hams know what is involved even if they do not understand the theory. It seems that many newer hams do not care - push the button on the microphone and make a contact is the limit of their interest. Perhaps we need to launch a renewed effort in bringing newer hams into the fold of understanding what is going on other than pushing the PTT button on the microphone. I hate to see the ranks of ham radio descend into the same category as CB operators, but I think we are headed that way as far as understanding what is involved in RF transmission and reception. If you want a computer parallel (for those digitally inclined) it is the difference between someone who only wants to do email and web surfing and those who understand (or attempt to learn) networking and how all that fits into the World Wide Web and Internet of Things. We do not have to fully understand propagation, circuits, antenna theory and such to push that PTT button and talk, but if that is all you do, it is more akin to CB than it is to amateur radio. OK, I will crawl off my soapbox for the time being. 73. Don W3FPR On 12/18/2018 8:00 PM, Fred Jensen wrote: Yep, the term was known when I became KN6DGW in 1953, but somehow no one cared. Standing waves were sort of benign, you ran your transmission line [often 300 ohm open-wire, or TV twinlead] to the 2 or 3 turn link and adjusted it inwards until your TX was "loaded" to rated input power. Standing waves formed the basis of "Lecher Lines" used to measure frequency [well ... wavelength] generally for VHF and above. Standing waves just didn't create the heartburn that they seem to today. Granted, today's TX are comfortable with 50 ohms and not much else but that's just impedance matching networks. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
This is probably the big reason. When I got my ticket, things were pretty much coax, but I vaguely remember something about open wire (ladder line) being less lossy when things were mismatched. 73 -- Lynn On 12/18/2018 5:00 PM, Fred Jensen wrote: Granted, today's TX are comfortable with 50 ohms and not much else but that's just impedance matching networks. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Yep, the term was known when I became KN6DGW in 1953, but somehow no one cared. Standing waves were sort of benign, you ran your transmission line [often 300 ohm open-wire, or TV twinlead] to the 2 or 3 turn link and adjusted it inwards until your TX was "loaded" to rated input power. Standing waves formed the basis of "Lecher Lines" used to measure frequency [well ... wavelength] generally for VHF and above. Standing waves just didn't create the heartburn that they seem to today. Granted, today's TX are comfortable with 50 ohms and not much else but that's just impedance matching networks. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/18/2018 3:32 PM, Wes Stewart wrote: T. A. Gadwa, “Standing Waves on Transmission Lines”, QST, December 1942, pp. 17-21. Wes N7WS __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
A few comments. 180 degree radiators are almost always avoided as at high power the base can literally be explosive. Theoretically 225 degrees would yield the most radiation towards the horizon but presents two problems. The first (for class A stations) is the secondary lobe that causes self interference skywave. The second issue is self loading where the radiator is longer electrically than it is physically. In such instance a 225 degree radiator is actually electrically longer causing the main lobe to lift off the ground and break into additional sidelobes. For that reason, class A stations opted for a compromise height of about 195 to 200 degrees. This lowers the base impedance over 180 degrees while limiting secondary skywave lobes to an acceptable level and staying in a safe area as far as self loading is concerned. Some class C (former class IV) stations use 225 degree radiators, though. Bandwidth is partially a function of the size of the tower face and also the design of the matching network. The problem becomes challenging when radiators get down around 60 degrees. There are two directional class A stations I can think of - WBZ Boston and WWL New Orleans. Both are very much alive and well and still quite successful. Sent from my iPad > On Dec 18, 2018, at 2:43 PM, Fred Jensen wrote: > > My mini-dissertation strictly applies to Class A [so-called "Clear Channel"] > stations only, who almost universally use single, omni-directional verticals > since they are not required to protect any other stations at night. There > were a few Class A's on the coasts that did use directional phased arrays > since there weren't many/any listeners out at sea but I don't know if any of > them are left. Non-Class A's generally employ 2 or sometimes 3 phased > verticals to achieve directional patterns at night to protect co-channel > stations, putting null(s) in the direction of their service areas. > > Class A's, such as KFI, seek to maximize the coverage in their service area > [i.e. maximize the area covered with an adequate field strength]. Neither a > 90-degree vertical ... current max at the bottom ... nor a 180-degree ... > current max half way up the tower ... will do that. At 640 KHz, a half-wave > is ~730 ft. > > The obsession with VSWR in ham radio is a bit surprising. I can't really > remember when the term became common, or when I first saw a VSWR bridge, but > I do know that I never saw one in SE Asia in the mid-60's. These days, high > VSWR seems to equate to "antenna that doesn't work." > > 73, > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 12/18/2018 12:38 PM, hawley, charles j jr wrote: >> Interesting, I had an analog computer course exercise at the U of I Urbana >> when we had two verticals separated and phased to define the coverage >> pattern. I don’t remember the length of them. It’d be interesting to recall >> what it was. >> >> Chuck >> KE9UW >> >> > > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
T. A. Gadwa, “Standing Waves on Transmission Lines”, QST, December 1942, pp. 17-21. Wes N7WS On 12/18/2018 3:43 PM, Fred Jensen wrote: [snip] The obsession with VSWR in ham radio is a bit surprising. I can't really remember when the term became common, or when I first saw a VSWR bridge, but I do know that I never saw one in SE Asia in the mid-60's. These days, high VSWR seems to equate to "antenna that doesn't work." 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Right, SWR (or VSWR = same thing) has nothing to do with the antenna itself - it is all related to the feedline. It does have a lot to do with the ability to match the feedline to the transceiver which normally likes a 50 ohm load or something close - but then an ATU can take care of that situation easily. Often a feedline is used as a matching section, and the reason it works is that SWR makes it work. See the antenna and feedline article on my website www.w3fpr.com. 73, Don W3FPR On 12/18/2018 5:43 PM, Fred Jensen wrote: The obsession with VSWR in ham radio is a bit surprising. I can't really remember when the term became common, or when I first saw a VSWR bridge, but I do know that I never saw one in SE Asia in the mid-60's. These days, high VSWR seems to equate to "antenna that doesn't work." __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Actually most are open wire feeders and have no networks. Sent from my iPad > On Dec 18, 2018, at 11:27 AM, Bob McGraw K4TAX wrote: > > But usually they have only 2 or 3 switched frequencies. They also switch > directions, sometimes on different frequencies. All of these conditions are > known and networks are pre set for the required combination. > > Bob, K4TAX > > > Sent from my iPhone > >> On Dec 18, 2018, at 12:35 PM, W2xj wrote: >> >> I was referring to ham tuners but shortwave broadcast stations QSY with >> hundreds of kilowatts many times a day. >> >> Sent from my iPad >> >>> On Dec 18, 2018, at 10:00 AM, Lynn W. Taylor, WB6UUT >>> wrote: >>> >>> How often does the match change at a well-engineered broadcast station? >>> On 12/18/2018 9:47 AM, W2xj wrote: That’s why we have adjustable antenna tuners. Same concept. Sent from my iPhone > On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT > wrote: > > Broadcast stations rarely QSY. >>> __ >>> 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 >>> Message delivered to w...@w2xj.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 >> Message delivered to rmcg...@blomand.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
My mini-dissertation strictly applies to Class A [so-called "Clear Channel"] stations only, who almost universally use single, omni-directional verticals since they are not required to protect any other stations at night. There were a few Class A's on the coasts that did use directional phased arrays since there weren't many/any listeners out at sea but I don't know if any of them are left. Non-Class A's generally employ 2 or sometimes 3 phased verticals to achieve directional patterns at night to protect co-channel stations, putting null(s) in the direction of their service areas. Class A's, such as KFI, seek to maximize the coverage in their service area [i.e. maximize the area covered with an adequate field strength]. Neither a 90-degree vertical ... current max at the bottom ... nor a 180-degree ... current max half way up the tower ... will do that. At 640 KHz, a half-wave is ~730 ft. The obsession with VSWR in ham radio is a bit surprising. I can't really remember when the term became common, or when I first saw a VSWR bridge, but I do know that I never saw one in SE Asia in the mid-60's. These days, high VSWR seems to equate to "antenna that doesn't work." 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/18/2018 12:38 PM, hawley, charles j jr wrote: Interesting, I had an analog computer course exercise at the U of I Urbana when we had two verticals separated and phased to define the coverage pattern. I don’t remember the length of them. It’d be interesting to recall what it was. Chuck KE9UW __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/18/2018 11:54 AM, Fred Jensen wrote: Indeed. AM broadcast vertical antennas are rarely 90 or 180 degrees, especially if they are a Class A station. I think both KFI and KNX in Los Angeles have 195 deg verticals. The design goal is to maximize field strength in the service area, accomplished by adjusting the height of the current maxima in the antenna element. Exactly right. Although I've never done the design work for them, I suspect that bandwidth can be increased by careful design of the matching networks. Technical details of US broadcast antenna systems can be queried from this link. https://www.fcc.gov/media/radio/am-query All resonance means is that the reactive component of the impedance at the feed point is zero. A bigger problem for stations at the low end of the band ... KFI is at 640 KHz ... is that the usable bandwidth of the antenna can be less than the bandwidth of the DSB signal. And it's an even bigger problem for stations using directional arrays! Those arrays are required by the terms of their license to protect other stations on the same or adjacent channels from interference. As a college student, I worked for one of those stations, and later for a consultant (Pete Johnson) who designed those arrays. Pete and Carl Smith wrote the technical sections of FCC Regs for AM BC after WWII. 73, Jim K9YC __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Interesting, I had an analog computer course exercise at the U of I Urbana when we had two verticals separated and phased to define the coverage pattern. I don’t remember the length of them. It’d be interesting to recall what it was. Chuck KE9UW Sent from my iPhone, cjack > On Dec 18, 2018, at 1:55 PM, Fred Jensen wrote: > > Indeed. AM broadcast vertical antennas are rarely 90 or 180 degrees, > especially if they are a Class A station. I think both KFI and KNX in Los > Angeles have 195 deg verticals. The design goal is to maximize field > strength in the service area, accomplished by adjusting the height of the > current maxima in the antenna element. All resonance means is that the > reactive component of the impedance at the feed point is zero. A bigger > problem for stations at the low end of the band ... KFI is at 640 KHz ... is > that the usable bandwidth of the antenna can be less than the bandwidth of > the DSB signal. [:-) Last time I saw KFI's tower from Interstate 5, it > appeared to have a fairly large capacity hat. > > Elecraft ATU's [even the KX1 which is necessarily small with a limited number > of L-C selections] seem to handle reactive loads just fine suggesting [to me > at least] that designing an antenna for azimuth and/or elevation pattern may > be more beneficial than achieving resonance in the desired part of the band. > > 73, > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 12/17/2018 7:45 PM, W2xj wrote: >> Coming from the broadcast side, especially AM broadcasting, I never >> considered resonance particularly important. Really it’s just the >> transmitter that cares. We always put matching at the antenna but in ham >> radio we usually have tuners at or in the TX. >> > > __ > 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 > Message delivered to c-haw...@illinois.edu __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
If I remember right, the first rule in designing a BC antenna, when dirt was new, was PATTERN coverage. Once that was achieved they fixed everything else. Resonance??? No one cared. Mel, K6KBE From: Fred Jensen To: elecraft@mailman.qth.net Sent: Tuesday, December 18, 2018 11:56 AM Subject: Re: [Elecraft] wire for random wire antenna using kx3 Indeed. AM broadcast vertical antennas are rarely 90 or 180 degrees, especially if they are a Class A station. I think both KFI and KNX in Los Angeles have 195 deg verticals. The design goal is to maximize field strength in the service area, accomplished by adjusting the height of the current maxima in the antenna element. All resonance means is that the reactive component of the impedance at the feed point is zero. A bigger problem for stations at the low end of the band ... KFI is at 640 KHz ... is that the usable bandwidth of the antenna can be less than the bandwidth of the DSB signal. [:-) Last time I saw KFI's tower from Interstate 5, it appeared to have a fairly large capacity hat. Elecraft ATU's [even the KX1 which is necessarily small with a limited number of L-C selections] seem to handle reactive loads just fine suggesting [to me at least] that designing an antenna for azimuth and/or elevation pattern may be more beneficial than achieving resonance in the desired part of the band. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/17/2018 7:45 PM, W2xj wrote: > Coming from the broadcast side, especially AM broadcasting, I never > considered resonance particularly important. Really it’s just the transmitter > that cares. We always put matching at the antenna but in ham radio we usually > have tuners at or in the TX. > __ 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 Message delivered to farrerfo...@yahoo.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Indeed. AM broadcast vertical antennas are rarely 90 or 180 degrees, especially if they are a Class A station. I think both KFI and KNX in Los Angeles have 195 deg verticals. The design goal is to maximize field strength in the service area, accomplished by adjusting the height of the current maxima in the antenna element. All resonance means is that the reactive component of the impedance at the feed point is zero. A bigger problem for stations at the low end of the band ... KFI is at 640 KHz ... is that the usable bandwidth of the antenna can be less than the bandwidth of the DSB signal. [:-) Last time I saw KFI's tower from Interstate 5, it appeared to have a fairly large capacity hat. Elecraft ATU's [even the KX1 which is necessarily small with a limited number of L-C selections] seem to handle reactive loads just fine suggesting [to me at least] that designing an antenna for azimuth and/or elevation pattern may be more beneficial than achieving resonance in the desired part of the band. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/17/2018 7:45 PM, W2xj wrote: Coming from the broadcast side, especially AM broadcasting, I never considered resonance particularly important. Really it’s just the transmitter that cares. We always put matching at the antenna but in ham radio we usually have tuners at or in the TX. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
But usually they have only 2 or 3 switched frequencies. They also switch directions, sometimes on different frequencies. All of these conditions are known and networks are pre set for the required combination. Bob, K4TAX Sent from my iPhone > On Dec 18, 2018, at 12:35 PM, W2xj wrote: > > I was referring to ham tuners but shortwave broadcast stations QSY with > hundreds of kilowatts many times a day. > > Sent from my iPad > >> On Dec 18, 2018, at 10:00 AM, Lynn W. Taylor, WB6UUT >> wrote: >> >> How often does the match change at a well-engineered broadcast station? >> >>> On 12/18/2018 9:47 AM, W2xj wrote: >>> That’s why we have adjustable antenna tuners. Same concept. >>> Sent from my iPhone On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT wrote: Broadcast stations rarely QSY. >> __ >> 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 >> Message delivered to w...@w2xj.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 > Message delivered to rmcg...@blomand.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I always put mine down about 3 feet. Avoids both farmers and copper thieves. Sent from my iPad > On Dec 18, 2018, at 10:21 AM, Bob McGraw K4TAX wrote: > > When the farmer plows up the ground field in the Spring! Gr > > 73 > > Bob, K4TAX > > >> On 12/18/2018 12:00 PM, Lynn W. Taylor, WB6UUT wrote: >> How often does the match change at a well-engineered broadcast station? >> >>> On 12/18/2018 9:47 AM, W2xj wrote: >>> That’s why we have adjustable antenna tuners. Same concept. >>> >>> Sent from my iPhone >>> On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT wrote: Broadcast stations rarely QSY. >> __ >> 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 >> Message delivered to rmcg...@blomand.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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I was referring to ham tuners but shortwave broadcast stations QSY with hundreds of kilowatts many times a day. Sent from my iPad > On Dec 18, 2018, at 10:00 AM, Lynn W. Taylor, WB6UUT > wrote: > > How often does the match change at a well-engineered broadcast station? > >> On 12/18/2018 9:47 AM, W2xj wrote: >> That’s why we have adjustable antenna tuners. Same concept. >> Sent from my iPhone >>> On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT >>> wrote: >>> >>> Broadcast stations rarely QSY. > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
When the farmer plows up the ground field in the Spring! Gr 73 Bob, K4TAX On 12/18/2018 12:00 PM, Lynn W. Taylor, WB6UUT wrote: How often does the match change at a well-engineered broadcast station? On 12/18/2018 9:47 AM, W2xj wrote: That’s why we have adjustable antenna tuners. Same concept. Sent from my iPhone On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT wrote: Broadcast stations rarely QSY. __ 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 Message delivered to rmcg...@blomand.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
How often does the match change at a well-engineered broadcast station? On 12/18/2018 9:47 AM, W2xj wrote: That’s why we have adjustable antenna tuners. Same concept. Sent from my iPhone On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT wrote: Broadcast stations rarely QSY. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
That’s why we have adjustable antenna tuners. Same concept. Sent from my iPhone > On Dec 18, 2018, at 09:27, Lynn W. Taylor, WB6UUT > wrote: > > Broadcast stations rarely QSY. > >> On 12/17/2018 7:45 PM, W2xj wrote: >> Coming from the broadcast side, especially AM broadcasting, I never >> considered resonance particularly important. Really it’s just the >> transmitter that cares. We always put matching at the antenna but in ham >> radio we usually have tuners at or in the TX. > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Broadcast stations rarely QSY. On 12/17/2018 7:45 PM, W2xj wrote: Coming from the broadcast side, especially AM broadcasting, I never considered resonance particularly important. Really it’s just the transmitter that cares. We always put matching at the antenna but in ham radio we usually have tuners at or in the TX. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Telephone drop wire makes a good antenna. Connect both wires for a fat dipole. But, be careful. The phone company uses a device on the end that attaches to the house that is a break-away in case a tree, etc falls across the wire. The stuff is so strong that it will pull the siding off your house. I knew of someone who used it in a community with C&R restrictions. He requested that he could put up a dog run. The dog run was actually his antenna. When asked why the dog run had a wire going to the side of his house and ground, he replied "lightning protection". He didn't want his dog electrocuted during a storm. The ultimate stealth antenna. 73, Joe, K1ike On 12/17/2018 11:39 PM, elecraft-requ...@mailman.qth.net wrote: if you can find telephone house service wire,,, is copper clad and impossible to brake makes good antenna,, not for use as feeders though __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Remote controlled tuner __ Clay Autery, KY5G (318) 518-1389 On 17-Dec-18 22:39, Don Wilhelm wrote: To my mind, a matching network at the antenna feedpoint can make an antenna a resonant antenna as far as the feedline and transmitter are concerned. But it is often a single band affair as is resonant dipoles. 73, Don W3FPR On 12/17/2018 10:45 PM, W2xj wrote: Coming from the broadcast side, especially AM broadcasting, I never considered resonance particularly important. Really it’s just the transmitter that cares. We always put matching at the antenna but in ham radio we usually have tuners at or in the TX. __ 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 Message delivered to k...@montac.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Beautifully put, Dave. I've had exactly the same experience, and I agree on all points. And, by the way, as I get older, I'd far rather be doing my learning in NEC and SimSmith than trudging through my woods or out on FD or county expeditions putting up antennas that don't work well enough to be worth the trouble! 73, Jim K9YC On 12/17/2018 4:52 PM, David Gilbert wrote: I've been modeling antennas using EZNEC since back when it was ELNEC, and I've learned more about how antennas work using it than by any other means. It is fascinating to set up some wires in the model, plant a source somewhere, and then look at the radiation pattern and current distributions. Having been very active in Field Day over several decades and trying out different antennas (often more than one) each year, I would be willing to bet $100 that I have physically built more functioning antennas than you have. Analyses paralyses my ass. The point is that analysis and practice are not mutually exclusive, and anything that helps us actually understand what we do instead of blind trail and error is worth the time and effort it takes. Learning by any means is not "bad" ... it is very, very good. Dave AB7E On 12/17/2018 2:22 PM, DC wrote: Good one! Many hams now-days miss the most important point of all, I have never made a contact by computer modeling, and worrying about wire type and size. Back in the day, you put something up and experimented from there -- making contacts along the way. Now, folks look at the internet and then second guess everything they read to the point of information overload and analyses paralyses. Too Bad, Richard K6VV __ 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 Message delivered to j...@audiosystemsgroup.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
The transmitter and feedline is all that matters. Of coarse, in broadcast only a single frequency needs to be matched. There are remotely controlled outdoor tuners for ham bands that perform the same or better than the typical indoor units. Sent from my iPhone > On Dec 17, 2018, at 20:39, Don Wilhelm wrote: > > To my mind, a matching network at the antenna feedpoint can make an antenna a > resonant antenna as far as the feedline and transmitter are concerned. > But it is often a single band affair as is resonant dipoles. > > 73, > Don W3FPR > >> On 12/17/2018 10:45 PM, W2xj wrote: >> Coming from the broadcast side, especially AM broadcasting, I never >> considered resonance particularly important. Really it’s just the >> transmitter that cares. We always put matching at the antenna but in ham >> radio we usually have tuners at or in the TX. >> >> > > __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
To my mind, a matching network at the antenna feedpoint can make an antenna a resonant antenna as far as the feedline and transmitter are concerned. But it is often a single band affair as is resonant dipoles. 73, Don W3FPR On 12/17/2018 10:45 PM, W2xj wrote: Coming from the broadcast side, especially AM broadcasting, I never considered resonance particularly important. Really it’s just the transmitter that cares. We always put matching at the antenna but in ham radio we usually have tuners at or in the TX. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Coming from the broadcast side, especially AM broadcasting, I never considered resonance particularly important. Really it’s just the transmitter that cares. We always put matching at the antenna but in ham radio we usually have tuners at or in the TX. Sent from my iPhone > On Dec 17, 2018, at 19:26, Don Wilhelm wrote: > > I am also a retired engineer, and I find that often it is quicker and easier > to put up an antenna cut to the "standard" formula (OK, I start a bit longer > than that), then check with an antenna analyzer and cut from there. Modeling > is great if you can take into consideration all factors such as height, > ground quality, surrounding objects, etc. - but it is difficult to consider > all that in advance. > > If your desire is to obtain the horizontal and vertical radiation patterns, > then modeling is the best way to do that. > > If you want to cut only once, use the technique I had published in QST > Technical Correspondence May 2018. > Cut the radiator to 468/F(MHz) plus 5 or 10%. > Measure the radiator length and put it in position. Then with your antenna > analyzer, measure the resonant frequency in MHz. Now multiply the actual > frequency times the length to find a new "cutting factor" (will be different > than 468). Divide that new 'cutting factor' by the desired resonant > frequency, and then trim the antenna to the new length - put it up and it > will work. > > Remember that the resonant frequency is where the "X" component of the > antenna is zero - it may be the same as the lowest SWR, but not necessarily > so. > > 73, > Don W3FPR > >> On 12/17/2018 9:56 PM, Fred Jensen wrote: >> Yes, to each his own. As a retired engineer, I relished the day I could >> forego all of the planning, research, design + review cycles, quality >> assurance reviews, prototype testing, test reviews, program management >> reviews, customer reviews and feedback, and 250K miles/year on United >> Airlines. I model antennas with EZNEC4, I'm old and endurance flags some >> before the trial antenna is up. > __ > 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 > Message delivered to w...@w2xj.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I am also a retired engineer, and I find that often it is quicker and easier to put up an antenna cut to the "standard" formula (OK, I start a bit longer than that), then check with an antenna analyzer and cut from there. Modeling is great if you can take into consideration all factors such as height, ground quality, surrounding objects, etc. - but it is difficult to consider all that in advance. If your desire is to obtain the horizontal and vertical radiation patterns, then modeling is the best way to do that. If you want to cut only once, use the technique I had published in QST Technical Correspondence May 2018. Cut the radiator to 468/F(MHz) plus 5 or 10%. Measure the radiator length and put it in position. Then with your antenna analyzer, measure the resonant frequency in MHz. Now multiply the actual frequency times the length to find a new "cutting factor" (will be different than 468). Divide that new 'cutting factor' by the desired resonant frequency, and then trim the antenna to the new length - put it up and it will work. Remember that the resonant frequency is where the "X" component of the antenna is zero - it may be the same as the lowest SWR, but not necessarily so. 73, Don W3FPR On 12/17/2018 9:56 PM, Fred Jensen wrote: Yes, to each his own. As a retired engineer, I relished the day I could forego all of the planning, research, design + review cycles, quality assurance reviews, prototype testing, test reviews, program management reviews, customer reviews and feedback, and 250K miles/year on United Airlines. I model antennas with EZNEC4, I'm old and endurance flags some before the trial antenna is up. __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Yes, to each his own. As a retired engineer, I relished the day I could forego all of the planning, research, design + review cycles, quality assurance reviews, prototype testing, test reviews, program management reviews, customer reviews and feedback, and 250K miles/year on United Airlines. I model antennas with EZNEC4, I'm old and endurance flags some before the trial antenna is up. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/17/2018 2:43 PM, W2xj wrote: Remember this IS a hobby and to each their own. As an engineer, I do model and design what I use. I hate the “by guess and by golly” approach. Everything I do is carefully planned in advance and is a part of my enjoyment of the hobby but YMMV. Sent from my iPad __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I've been modeling antennas using EZNEC since back when it was ELNEC, and I've learned more about how antennas work using it than by any other means. It is fascinating to set up some wires in the model, plant a source somewhere, and then look at the radiation pattern and current distributions. Having been very active in Field Day over several decades and trying out different antennas (often more than one) each year, I would be willing to bet $100 that I have physically built more functioning antennas than you have. Analyses paralyses my ass. The point is that analysis and practice are not mutually exclusive, and anything that helps us actually understand what we do instead of blind trail and error is worth the time and effort it takes. Learning by any means is not "bad" ... it is very, very good. Dave AB7E On 12/17/2018 2:22 PM, DC wrote: Good one! Many hams now-days miss the most important point of all, I have never made a contact by computer modeling, and worrying about wire type and size. Back in the day, you put something up and experimented from there -- making contacts along the way. Now, folks look at the internet and then second guess everything they read to the point of information overload and analyses paralyses. Too Bad, Richard K6VV __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
> On Dec 17, 2018, at 1:22 PM, DC wrote: > > Many hams now-days miss the most important point of all, I have never made a > contact by computer modeling, and worrying about wire type and size. But how many contacts have been missed because people didn’t do computer modeling or worry about wire? wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
wow I am so embarised Bob K3DJC On Mon, 17 Dec 2018 17:25:10 -0500 Don Wilhelm writes: > Does this mean that the electrons just will not stop? > I brake my car when I need to stop it. > I fix it when it it breaks. > > If I pull on the wire enough, it certainly will break. > > Proper spelling equals meaningful words - the English language is > complicated, but I thought we learned many of the spelling > differences > in grade 6 - here vs. hear, there vs. their, etc. even though they > sound > the same. > It seems that texting and "OMG", "LOL" and such have devalued our > use of > good language and spelling skills. > > 73, > Don W3FPR > > On 12/17/2018 4:24 PM, riese-k3...@juno.com wrote: > > if you can find telephone house service wire,,, is copper clad > and > > impossible to brake > __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Remember this IS a hobby and to each their own. As an engineer, I do model and design what I use. I hate the “by guess and by golly” approach. Everything I do is carefully planned in advance and is a part of my enjoyment of the hobby but YMMV. Sent from my iPad > On Dec 17, 2018, at 1:22 PM, DC wrote: > > Good one! > > > Many hams now-days miss the most important point of all, I have never made a > contact by computer modeling, and worrying about wire type and size. Back in > the day, you put something up and experimented from there -- making contacts > along the way. Now, folks look at the internet and then second guess > everything they read to the point of information overload and analyses > paralyses. > > Too Bad, > > Richard > > K6VV > > >> On 12/17/2018 7:09 AM, Charlie T wrote: >> Yes, but speaker wire is only good for audio up to about 25 kHz. It has a >> frequency limiting component in the wire alloy that must be removed in order >> to use this type wire at RF. >> >> This removal procedure is fairly easy to accomplish. First, soak the wire >> in a bucket of laundry detergent and water over night, then remove the wire >> and rinse it thoroughly. >> After assuring the wire is dry, place in an oven set to about 150 degrees >> for about 3 - 4 hours. >> In lieu of the oven, you can also place the wire in an afternoon of summer >> sun. >> After that, place the wire on the ground and hold a 2 meter hand-held over >> the wire, approximately a foot away and key up the radio for 20 seconds at a >> couple watts output. >> If you see no reaction, sparking, especially tingling in your ears, or >> physical movement of the wire, it is now safe to use as an antenna. >> >> Note this advice is given freely and may be disseminated with no intended >> royalty charges or copyright infringements. >> >> 73, Charlie k3ICH >> >> >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net On >> Behalf Of Don Wilhelm >> Sent: Monday, December 17, 2018 9:46 AM >> To: Richard watson ; elecraft >> >> Subject: Re: [Elecraft] wire for random wire antenna using kx3 >> >> Rick, >> >> Certainly it will work, and makes for a quick temporary antenna, >> particularly indoors. >> However, if you are using the speaker wire as a transmission line, it has >> relatively high loss characteristics, and I would recommend that you think >> about replacing the transmission line part with real parallel transmission >> line for a more permanent installation. >> >> For the radiator section, the speaker wire can remain. >> >> 73, >> Do __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Does this mean that the electrons just will not stop? I brake my car when I need to stop it. I fix it when it it breaks. If I pull on the wire enough, it certainly will break. Proper spelling equals meaningful words - the English language is complicated, but I thought we learned many of the spelling differences in grade 6 - here vs. hear, there vs. their, etc. even though they sound the same. It seems that texting and "OMG", "LOL" and such have devalued our use of good language and spelling skills. 73, Don W3FPR On 12/17/2018 4:24 PM, riese-k3...@juno.com wrote: if you can find telephone house service wire,,, is copper clad and impossible to brake __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/18 3:11 PM, Jim Brown wrote: > This overly simplified equation fails to account for proximity effe Proximity effect will effect impedance, which will then effect the loss. The wire loss equation is dependent on the TL Zo. The previous example was for Zo=100. Using Zo=75, wire loss for #12 is 0.47 dB/100. For the Teflon, that would leave 0.47 dB for dielectric loss. This is sounding closer. John KN5L > On 12/17/2018 12:58 PM, John Oppenheimer wrote: >> On 12/17/18 1:58 PM, Jim Brown wrote: >>> In order of loss at dB/100 ft at 10 MHz from low to high, the >>> Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as >>> RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the >>> greatest loss, 2.4 dB/100 ft. >> Hi Jim, >> >> Two parallel transmission line is the easiest of all to evaluate using a >> RF resistance table and knowing the impedance of the line. >> http://ve3efc.ca/wireohms.htm >> >> The wire loss is dB = 10 * log10((Zo + WireR)/Zo) >> >> Assuming Zo=100 for the #12 Teflon and THHN. R at 10 MHz = 4.24/100 = >> 8.48/200. >> >> Wire dB = 10 * log10(108.48 / 100) = 0.35 dB >> >> Using the two values above at 10 MHz, 0.94 and 1.34, the dielectric loss >> is 0.59 dB and 1 dB. The dielectric loss is about two and three times >> the wire loss. >> >> John KN5L __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
if you can find telephone house service wire,,, is copper clad and impossible to brake Bob K3DJC On Mon, 17 Dec 2018 09:04:04 -0900 Edward R Cole writes: > I see the humour genes is alive and well in some hams! > > But seriously plastic coated wire will work on HF antennas, though > you may see a slight lenthening of resonant length vs bare wire. > > My 80m/40m fan inverted-V is made of coated copper-weld and I just > tuned it using my MFJ-269B antenna analyzer. My 43 by 122-foot > inverted-L (630m band) is also the same copper-weld steel. It uses > a > huge base coil that set the tap for resonance. Z = 20 +0j It warms > > worms well in the winter with 100w input and 4w EIRP. > > Years ago I made a light-weight 80m dipole using 18ga speaker > wire. Worked Anchorage over 500 mi with 100w from a checkpoint on > the Iditarod Sled Dog race. > > 73, Ed - KL7UW >http://www.kl7uw.com > Dubus-NA Business mail: >dubus...@gmail.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 > Message delivered to riese-k3...@juno.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
if you can find telephone house service wire,,, is copper clad and impossible to brake makes good antenna,, not for use as feeders though Bob K3DJC > > > On Mon, 17 Dec 2018 09:04:04 -0900 Edward R Cole > writes: > > I see the humour genes is alive and well in some hams! > > > > But seriously plastic coated wire will work on HF antennas, though > > > you may see a slight lenthening of resonant length vs bare wire. > > > > My 80m/40m fan inverted-V is made of coated copper-weld and I just > > > tuned it using my MFJ-269B antenna analyzer. My 43 by 122-foot > > inverted-L (630m band) is also the same copper-weld steel. It > uses > > a > > huge base coil that set the tap for resonance. Z = 20 +0j It > warms > > > > worms well in the winter with 100w input and 4w EIRP. > > > > Years ago I made a light-weight 80m dipole using 18ga speaker > > wire. Worked Anchorage over 500 mi with 100w from a checkpoint on > > > the Iditarod Sled Dog race. > > > > 73, Ed - KL7UW > >http://www.kl7uw.com > > Dubus-NA Business mail: > >dubus...@gmail.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 > > Message delivered to riese-k3...@juno.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Good one! Many hams now-days miss the most important point of all, I have never made a contact by computer modeling, and worrying about wire type and size. Back in the day, you put something up and experimented from there -- making contacts along the way. Now, folks look at the internet and then second guess everything they read to the point of information overload and analyses paralyses. Too Bad, Richard K6VV On 12/17/2018 7:09 AM, Charlie T wrote: Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Don Wilhelm Sent: Monday, December 17, 2018 9:46 AM To: Richard watson ; elecraft Subject: Re: [Elecraft] wire for random wire antenna using kx3 Rick, Certainly it will work, and makes for a quick temporary antenna, particularly indoors. However, if you are using the speaker wire as a transmission line, it has relatively high loss characteristics, and I would recommend that you think about replacing the transmission line part with real parallel transmission line for a more permanent installation. For the radiator section, the speaker wire can remain. 73, Don W3FPR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to vetteresto...@gmail.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
This overly simplified equation fails to account for proximity effect. On 12/17/2018 12:58 PM, John Oppenheimer wrote: On 12/17/18 1:58 PM, Jim Brown wrote: In order of loss at dB/100 ft at 10 MHz from low to high, the Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the greatest loss, 2.4 dB/100 ft. Hi Jim, Two parallel transmission line is the easiest of all to evaluate using a RF resistance table and knowing the impedance of the line. http://ve3efc.ca/wireohms.htm The wire loss is dB = 10 * log10((Zo + WireR)/Zo) Assuming Zo=100 for the #12 Teflon and THHN. R at 10 MHz = 4.24/100 = 8.48/200. Wire dB = 10 * log10(108.48 / 100) = 0.35 dB Using the two values above at 10 MHz, 0.94 and 1.34, the dielectric loss is 0.59 dB and 1 dB. The dielectric loss is about two and three times the wire loss. John KN5L __ 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 Message delivered to j...@audiosystemsgroup.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/18 1:58 PM, Jim Brown wrote: > In order of loss at dB/100 ft at 10 MHz from low to high, the > Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as > RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the > greatest loss, 2.4 dB/100 ft. Hi Jim, Two parallel transmission line is the easiest of all to evaluate using a RF resistance table and knowing the impedance of the line. http://ve3efc.ca/wireohms.htm The wire loss is dB = 10 * log10((Zo + WireR)/Zo) Assuming Zo=100 for the #12 Teflon and THHN. R at 10 MHz = 4.24/100 = 8.48/200. Wire dB = 10 * log10(108.48 / 100) = 0.35 dB Using the two values above at 10 MHz, 0.94 and 1.34, the dielectric loss is 0.59 dB and 1 dB. The dielectric loss is about two and three times the wire loss. John KN5L __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I miss good old WIOU. He had some technical insights which were unique, to say the least. Bob, N7XY On 12/17/18 11:03 AM, Fred Jensen wrote: Larson E. Rapp is using an alias now? 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/17/2018 7:09 AM, Charlie T wrote: Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH __ 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 Message delivered to n...@n7xy.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I didn't think from the original post that this was going to be used as transmission line. I pictured simply tying both sides of the speaker wire to one terminal on the UN-UN. Speaker wire because he has it, vs. buying wire specifically for a temporary antenna. "Random wire" so the 9:1 transformer is needed if it's close to a resonant length and he's feeding the end, maybe not if the wire is some non-resonant length, like 53 feet or so. 73 -- Lynn On 12/17/2018 11:58 AM, Jim Brown wrote: On 12/17/2018 6:45 AM, Don Wilhelm wrote: However, if you are using the speaker wire as a transmission line, it has relatively high loss characteristics Compared to what? So-called speaker wire (which is really lousy for speakers because it should be twisted pair to minimize RFI) has Zo in the range of 75-100 ohms. Unless it's wet, virtually all the loss in transmission lines below about 100 MHz is due to wire resistance, not dielectric loss. There is, of course, additional loss due to any mismatch that may be present, but that still comes down to loss in the resistance of the line. While I haven't measured any zip cord, I've measured a lot of closely spaced parallel wire transmission line made from THHN, enameled copper, and Teflon insulated #12 silver-coated copper. In order of loss at dB/100 ft at 10 MHz from low to high, the Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the greatest loss, 2.4 dB/100 ft. 73, Jim K9YC __ 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 Message delivered to kx...@coldrockshotbrooms.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
On 12/17/2018 6:45 AM, Don Wilhelm wrote: However, if you are using the speaker wire as a transmission line, it has relatively high loss characteristics Compared to what? So-called speaker wire (which is really lousy for speakers because it should be twisted pair to minimize RFI) has Zo in the range of 75-100 ohms. Unless it's wet, virtually all the loss in transmission lines below about 100 MHz is due to wire resistance, not dielectric loss. There is, of course, additional loss due to any mismatch that may be present, but that still comes down to loss in the resistance of the line. While I haven't measured any zip cord, I've measured a lot of closely spaced parallel wire transmission line made from THHN, enameled copper, and Teflon insulated #12 silver-coated copper. In order of loss at dB/100 ft at 10 MHz from low to high, the Teflon #12 is lowest at 0.94dB, then RG400 at 1.22 dB (about the same as RG58), then #12 THHN at 1.34 dB. #12 or #10 enameled copper had the greatest loss, 2.4 dB/100 ft. 73, Jim K9YC __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Larson E. Rapp is using an alias now? 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 12/17/2018 7:09 AM, Charlie T wrote: Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
I see the humour genes is alive and well in some hams! But seriously plastic coated wire will work on HF antennas, though you may see a slight lenthening of resonant length vs bare wire. My 80m/40m fan inverted-V is made of coated copper-weld and I just tuned it using my MFJ-269B antenna analyzer. My 43 by 122-foot inverted-L (630m band) is also the same copper-weld steel. It uses a huge base coil that set the tap for resonance. Z = 20 +0j It warms worms well in the winter with 100w input and 4w EIRP. Years ago I made a light-weight 80m dipole using 18ga speaker wire. Worked Anchorage over 500 mi with 100w from a checkpoint on the Iditarod Sled Dog race. 73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: dubus...@gmail.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Be sure the wire is LCOF copper. The electrons are reported to move faster and with less resistance in that medium. This makes your signal get to the DX station faster than anyone else . HA HA HA Seriously folks, to evaluate the insulation on the zip cord or speaker wire, my method is to strip off about 6" of the insulation. Be sure there's no copper left inside. Then put the insulation in the microwave along with a cup of water for a microwave load. Heat for about 30 seconds. If the insulation is hot, it is not good for RF properties. If the insulation is cool, it is OK for RF. I would suspect that color may have different results. Try clear, brown, white, black to see if there is any difference. If the insulation meltsclean the microwave before the XYL discovers the mess. I find that #16 to #18 zip cord, is nominally about 75 ohms Z and in my portable operation I work with 100 watts without any known issues. 73 Bob, K4TAX __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
April came fast! K9ZTV On 12/17/2018 9:28 AM, Don Wilhelm wrote: Ha, Ha, Ha, Ha! Where can we find that information? Website please. 73, Don W3FPR On 12/17/2018 10:09 AM, Charlie T wrote: Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH __ 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 Message delivered to k9...@socket.net --- This email has been checked for viruses by AVG. https://www.avg.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Ha, Ha, Ha, Ha! Where can we find that information? Website please. 73, Don W3FPR On 12/17/2018 10:09 AM, Charlie T wrote: Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Yes, but speaker wire is only good for audio up to about 25 kHz. It has a frequency limiting component in the wire alloy that must be removed in order to use this type wire at RF. This removal procedure is fairly easy to accomplish. First, soak the wire in a bucket of laundry detergent and water over night, then remove the wire and rinse it thoroughly. After assuring the wire is dry, place in an oven set to about 150 degrees for about 3 - 4 hours. In lieu of the oven, you can also place the wire in an afternoon of summer sun. After that, place the wire on the ground and hold a 2 meter hand-held over the wire, approximately a foot away and key up the radio for 20 seconds at a couple watts output. If you see no reaction, sparking, especially tingling in your ears, or physical movement of the wire, it is now safe to use as an antenna. Note this advice is given freely and may be disseminated with no intended royalty charges or copyright infringements. 73, Charlie k3ICH -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Don Wilhelm Sent: Monday, December 17, 2018 9:46 AM To: Richard watson ; elecraft Subject: Re: [Elecraft] wire for random wire antenna using kx3 Rick, Certainly it will work, and makes for a quick temporary antenna, particularly indoors. However, if you are using the speaker wire as a transmission line, it has relatively high loss characteristics, and I would recommend that you think about replacing the transmission line part with real parallel transmission line for a more permanent installation. For the radiator section, the speaker wire can remain. 73, Don W3FPR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Rick, Certainly it will work, and makes for a quick temporary antenna, particularly indoors. However, if you are using the speaker wire as a transmission line, it has relatively high loss characteristics, and I would recommend that you think about replacing the transmission line part with real parallel transmission line for a more permanent installation. For the radiator section, the speaker wire can remain. 73, Don W3FPR On 12/17/2018 8:10 AM, Richard watson wrote: Good morning list, I was wondering what folks thought about using speaker wire for a quick indoor antenna for my kx3. I've got one of those nelson antennas 9:1 unun and the tuner in the kx3. Do I need heavier wire and would that make a difference? thanks and 73 - rick n3gms __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Hi Rick, I don't think so. I use speaker wire with my EARCHI antenna--maybe 18-20 gauge-- 25' of coax, 9:1 un-un, and it works just fine. Also a KX3. 73, John K4ARQ On Mon, Dec 17, 2018, 08:12 Richard watson Good morning list, > I was wondering what folks thought about using speaker wire for a > quick indoor antenna for my kx3. > I've got one of those nelson antennas 9:1 unun and the tuner in the > kx3. Do I need heavier wire and would that make a difference? > thanks and 73 - rick n3gms > __ > 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 > Message delivered to gio.fl...@gmail.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] wire for random wire antenna using kx3
Rick - I think speaker wire would work just fine. Up to a point, wire is wire. I used some #18 insulated wire, with a 9:1 un-un and a KX3 while visiting in Florida several years ago. I ran the wire between two trees, as high as I could get it, and the tuner in the KX3 matched it on 160 through 10 meters. It was temporary, as I was down there for only 3 weeks, but I had a ball, and was amazed at how well it worked, all around the globe. 73 es gl de Dave - K9FN On Mon, Dec 17, 2018 at 8:11 AM Richard watson < richard.watson15...@gmail.com> wrote: > Good morning list, > I was wondering what folks thought about using speaker wire for a > quick indoor antenna for my kx3. > I've got one of those nelson antennas 9:1 unun and the tuner in the > kx3. Do I need heavier wire and would that make a difference? > thanks and 73 - rick n3gms > __ > 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 > Message delivered to dpbu...@gmail.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 Message delivered to arch...@mail-archive.com
[Elecraft] wire for random wire antenna using kx3
Good morning list, I was wondering what folks thought about using speaker wire for a quick indoor antenna for my kx3. I've got one of those nelson antennas 9:1 unun and the tuner in the kx3. Do I need heavier wire and would that make a difference? thanks and 73 - rick n3gms __ 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 Message delivered to arch...@mail-archive.com
