Re: [Elecraft] Franklin antennas
On 9/11/2018 4:23 PM, Gmail wrote: > KDKA, Pittsburgh, still has a Franklin, they are not a center fed > vertical. both the bottom and top sections are end fed. KNBR San Francisco has a similar antenna. I had been calling that a "Franklin" for decades until I was corrected - a true "Franklin" is a center-fed HW vertical dipole. (Sorry if this is OT/Closed) 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 (FCC District Director - Retired) >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] Franklin antennas
Correction, it was center fed. Sent from my iPad > On Sep 11, 2018, at 19:23, Gmail wrote: > > KDKA, Pittsburgh, still has a Franklin, they are not a center fed vertical. > both the bottom and top sections are end fed. The purpose is to lower angle > of radiation and reduce skywave and selective fading. KDKA has a motorized > capacitor on the top section. Both stations have extensive ground systems > that would not be needed if they were dipoles. > KDs antenna was replaced in 1994. Still a Franklin as changing the antenna > would have required a power reduction with the “ratchet rule”. > Ray > W8LYJ > Formerly with Group W Engineering, owner of both stations until recently. > > http://www.durenberger.com/documents/KDKANEWTOWER.pdf > Sent from my iPad > > >> >> Message: 1 >> Date: Sun, 9 Sep 2018 15:48:48 -0700 >> From: Fred Jensen >> To: elecraft@mailman.qth.net >> Subject: Re: [Elecraft] ARRL book on receiving antennas >> Message-ID: >> Content-Type: text/plain; charset=utf-8; format=flowed >> >> Yes, very straightforward theory.? Just gather all the watts actually >> radiated by the antenna and divide it by the watts you put into Rr.? >> Unfortunately, I did not really address Bob's question ... "How do you >> sweep up all those watts?" :-)? That is a nearly intractable problem at >> HF unless you'll tolerate significant inaccuracies and assumptions.? >> It's much easier at UHF and uWaves. >> >> An alternative is to measure/compute the losses.? Did something similar >> on a 10 KW FM broadcast TX, calculating the power it took to heat the >> exhaust air on the premise that the rest went up the coax to the antenna >> and I knew what the PA input power was. >> >> KFBK in Sacramento CA [1530 KHz] eliminated a lot of the unmeasurable >> variables by employing a Franklin antenna [center-fed half-wave >> vertical] over the rice fields of the southern Sacramento Valley [nearly >> always standing water, and always wet]. The center-fed vertical exhibits >> far less ground losses than bottom-fed monopoles ... at 50 KW, it's >> colloquially known as the "Flame Thrower of Sacramento."? It may be the >> only Franklin left in NA.? KFBK is also famous as the birthplace of the >> RCA Ampliphase transmitters and the radio birthplace of Rush Limbaugh. >> >> NEC models coupled with terrain models can be used to establish upper >> and lower bounds on antenna efficiency with pretty good fidelity to >> reality.? But Bob still posed a good question. >> >> 73, >> >> Fred ["Skip"] K6DGW >> Sparks NV DM09dn >> Washoe County >> >>> On 9/9/2018 2:01 PM, Don Wilhelm wrote: >>> Skip, >>> >>> That is a great formula for theory - I vaguely remember it from my >>> electromagnetic fields course. >>> But how you measure it? >>> With practical measurement equipment, it is difficult to isolate to a >>> single plane. >>> >>> That may be do-able with fully characterized equipment in a controlled >>> antenna field space or in an EMC lab, but it certainly is not >>> practical in a typical ham antenna installation - and even the >>> radiation resistance is not easily measured. >>> >>> Antenna modeling done properly will provide a much more easily >>> produced result.? Comparative results between different antennas can >>> be obtained from a reference pickup antenna, but that can only show >>> the relative performance, >> >> >> >> -- >> >> Message: 4 >> Date: Sun, 9 Sep 2018 17:20:17 -0700 >> From: Alan >> To: elecraft@mailman.qth.net >> Subject: Re: [Elecraft] ARRL book on receiving antennas >> Message-ID: <96b660d3-5a7d-cb60-8d1d-827aaa6d7...@sonic.net> >> Content-Type: text/plain; charset=utf-8; format=flowed >> >>> On 09/09/2018 01:01 PM, Jim Brown wrote: On 9/9/2018 12:39 PM, Bob McGraw K4TAX wrote: How does one measure transmit antenna efficiency? >>> >>> Not easily. :)? B... >> >>> AND -- propagation reporting systems like WSPR and the Reverse Beacon >>> Network (RBN) can provide very good comparisons between antennas IF a >>> LOT of reports from? a LOT of stations is averaged over a LOT of time. >> >> Back in the late 1970s, when I worked at W1AW, a new 90-foot tower with >> stacked monobanders for 20 meters was installed. We wanted to compare >> the new antenna against the big rhombic that had been used for many >> years for the 20 meter bulletin and code practice transmissions. >> >> So, for a week or two, we did test transmissions after each scheduled >> transmitting session. We would switch between antenna "A" and antenna >> "B", send long dashes, and ask listeners to send in QSL reports. (Which >> antenna was "A" and which was "B" varied randomly for each test.) >> >> I collected the reports and plotted them on a map of the US. We found >> that the rhombic was a little better directly on its boresight to the >> west (toward southern California from Connecticut) but the stacked Yagis >> had a much wider beamwidth so
[Elecraft] Franklin antennas
KDKA, Pittsburgh, still has a Franklin, they are not a center fed vertical. both the bottom and top sections are end fed. The purpose is to lower angle of radiation and reduce skywave and selective fading. KDKA has a motorized capacitor on the top section. Both stations have extensive ground systems that would not be needed if they were dipoles. KDs antenna was replaced in 1994. Still a Franklin as changing the antenna would have required a power reduction with the “ratchet rule”. Ray W8LYJ Formerly with Group W Engineering, owner of both stations until recently. http://www.durenberger.com/documents/KDKANEWTOWER.pdf Sent from my iPad > > > Message: 1 > Date: Sun, 9 Sep 2018 15:48:48 -0700 > From: Fred Jensen > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] ARRL book on receiving antennas > Message-ID: > Content-Type: text/plain; charset=utf-8; format=flowed > > Yes, very straightforward theory.? Just gather all the watts actually > radiated by the antenna and divide it by the watts you put into Rr.? > Unfortunately, I did not really address Bob's question ... "How do you > sweep up all those watts?" :-)? That is a nearly intractable problem at > HF unless you'll tolerate significant inaccuracies and assumptions.? > It's much easier at UHF and uWaves. > > An alternative is to measure/compute the losses.? Did something similar > on a 10 KW FM broadcast TX, calculating the power it took to heat the > exhaust air on the premise that the rest went up the coax to the antenna > and I knew what the PA input power was. > > KFBK in Sacramento CA [1530 KHz] eliminated a lot of the unmeasurable > variables by employing a Franklin antenna [center-fed half-wave > vertical] over the rice fields of the southern Sacramento Valley [nearly > always standing water, and always wet]. The center-fed vertical exhibits > far less ground losses than bottom-fed monopoles ... at 50 KW, it's > colloquially known as the "Flame Thrower of Sacramento."? It may be the > only Franklin left in NA.? KFBK is also famous as the birthplace of the > RCA Ampliphase transmitters and the radio birthplace of Rush Limbaugh. > > NEC models coupled with terrain models can be used to establish upper > and lower bounds on antenna efficiency with pretty good fidelity to > reality.? But Bob still posed a good question. > > 73, > > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 9/9/2018 2:01 PM, Don Wilhelm wrote: >> Skip, >> >> That is a great formula for theory - I vaguely remember it from my >> electromagnetic fields course. >> But how you measure it? >> With practical measurement equipment, it is difficult to isolate to a >> single plane. >> >> That may be do-able with fully characterized equipment in a controlled >> antenna field space or in an EMC lab, but it certainly is not >> practical in a typical ham antenna installation - and even the >> radiation resistance is not easily measured. >> >> Antenna modeling done properly will provide a much more easily >> produced result.? Comparative results between different antennas can >> be obtained from a reference pickup antenna, but that can only show >> the relative performance, > > > > -- > > Message: 4 > Date: Sun, 9 Sep 2018 17:20:17 -0700 > From: Alan > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] ARRL book on receiving antennas > Message-ID: <96b660d3-5a7d-cb60-8d1d-827aaa6d7...@sonic.net> > Content-Type: text/plain; charset=utf-8; format=flowed > >> On 09/09/2018 01:01 PM, Jim Brown wrote: >>> On 9/9/2018 12:39 PM, Bob McGraw K4TAX wrote: >>> How does one measure transmit antenna efficiency? >> >> Not easily. :)? B... > >> AND -- propagation reporting systems like WSPR and the Reverse Beacon >> Network (RBN) can provide very good comparisons between antennas IF a >> LOT of reports from? a LOT of stations is averaged over a LOT of time. > > Back in the late 1970s, when I worked at W1AW, a new 90-foot tower with > stacked monobanders for 20 meters was installed. We wanted to compare > the new antenna against the big rhombic that had been used for many > years for the 20 meter bulletin and code practice transmissions. > > So, for a week or two, we did test transmissions after each scheduled > transmitting session. We would switch between antenna "A" and antenna > "B", send long dashes, and ask listeners to send in QSL reports. (Which > antenna was "A" and which was "B" varied randomly for each test.) > > I collected the reports and plotted them on a map of the US. We found > that the rhombic was a little better directly on its boresight to the > west (toward southern California from Connecticut) but the stacked Yagis > had a much wider beamwidth so were better over the country as a whole. > > By the way, you don't have to transmit to compare two antennas if your > receiver has an accurate S meter. Just switch between the antennas and > compare S meter readings.
[Elecraft] T1 tuner kit
I recently picked up a kit built T1 tuner which doesnt quite work. On power up the yellow led flashes thrice then then stops and thats all we get. It is not well built so Im going to reflow all joints and carefully check everything, BUT, I wonder whether anyone else has come across this fault mode before who could give me a heads up as to its cause. David G4YVM __ 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] Test
Yes Chuck Jack KE9UW Sent from my iPhone, cjack > On Sep 11, 2018, at 1:38 PM, KE8G wrote: > > Are my emails making it to the list? > > 73 de Jim - KE8G > __ > 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] Test
Ok, great! Thanks for all the replies. 73 de Jim - KE8G On Tue, Sep 11, 2018 at 2:47 PM Michael Walker wrote: > The idiot in me wants to say no. LOL > > Obviously, it is working fine! 73 > > On Tue, Sep 11, 2018 at 2:37 PM, KE8G wrote: > >> Are my emails making it to the list? >> >> 73 de Jim - KE8G >> __ >> 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 va...@portcredit.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] Test
The idiot in me wants to say no. LOL Obviously, it is working fine! 73 On Tue, Sep 11, 2018 at 2:37 PM, KE8G wrote: > Are my emails making it to the list? > > 73 de Jim - KE8G > __ > 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 va...@portcredit.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
[Elecraft] Test
Are my emails making it to the list? 73 de Jim - KE8G __ 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] Off Topic: Fluke Multimeter for Sale
I have for sale a like-new Fluke model 87-V multimeter along with extra accessories. This is the industry standard handheld meter for electronics work. 4.5 digit display, 0.05% accuracy, extensive capacitance measuring capability, temperature measurement with included probe and legendary Fluke quality / reliability / durability. This model is still in production today and is Fluke’s top-of-the-line electronics handheld meter. I purchased this new in 2010 and it has since been used only in my lab while I had my consulting business. I’ve since retired and moved to a condo, so no longer have need for an instrument of this accuracy. This unit is in mint condition. It has always worked perfectly. Your purchase includes the meter, all original accessories including probes, the thermocouple probe, original box, manual, paperwork and DVD. I’m also including another like-new set of Fluke industrial probes with interchangeable tips, including alligator clips, clamps and clip-on hooked probes.Also included are some Probe Master mini-clip-on probes, BNC adapters, etc. The street price for this meter is currently $387.I’m asking $220 for the meter, accessories and additional extras including USPS insured Priority Mail shipping to the lower 48.Payment via PayPal. Photos by request. Contact me via email if interested. My email address OK on QRZ. Thanks and 73 CraigAC0DS __ 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] K1 80m Band Kit
Does anyone happen to have one of these that could benefit from being re-homed? 73 - Al, K2ZN Sent via mobile __ 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
