Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
I agree on the overthinking. How about the Elecraft AX1 ant? All you need extra is coax and a tripod. It takes me 10-15 min max to get on the air. The only limitation is no 80, 60 and 10 meters Sorta works on these bands if you play with the whip and use the ATU. YMMV 73Jim Hk7sss. In a message dated 12/13/2020 12:40:10 PM Pacific Standard Time, ghyoung...@gmail.com writes: I can’t help but think we’re over-thinking this. I think the original post was regarding ‘portable' operation. When I go portable I don’t carry a large antenna with lots of wire or weight. I usually carry a 41’ (non-resonant) wire with a 9:1 unun rated at 300w watts, and a throwing line and weight to get the far end of the wire up in a tree. I have a large OCFD and a 40’ fiberglass’s mast to get it up, but frankly, for quickie portable, getting the center pole staked and up and guyed is more trouble than its worth. If it was for a weekend or a week, maybe. But I’d rather spend the time operating. I’ve used the simple wire with both a K3 and KX3 with internal ATUs. Works fine. Nothing has ever cooked. The internal ATUs typically get SWR to 1.2:1 or better. Feedline is 25 feet of RG-58 choked off a foot before the radio termination. Sure, some power is getting lost in the tuner, the balun, the feedline, the connectors, human absorption, whatever. But … Grant NQ5T __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
I can’t help but think we’re over-thinking this. I think the original post was regarding ‘portable' operation. When I go portable I don’t carry a large antenna with lots of wire or weight. I usually carry a 41’ (non-resonant) wire with a 9:1 unun rated at 300w watts, and a throwing line and weight to get the far end of the wire up in a tree. I have a large OCFD and a 40’ fiberglass’s mast to get it up, but frankly, for quickie portable, getting the center pole staked and up and guyed is more trouble than its worth. If it was for a weekend or a week, maybe. But I’d rather spend the time operating. I’ve used the simple wire with both a K3 and KX3 with internal ATUs. Works fine. Nothing has ever cooked. The internal ATUs typically get SWR to 1.2:1 or better. Feedline is 25 feet of RG-58 choked off a foot before the radio termination. Sure, some power is getting lost in the tuner, the balun, the feedline, the connectors, human absorption, whatever. But … Grant NQ5T > On Dec 13, 2020, at 2:19 PM, donov...@erols.com wrote: > > Examining the KAT3A circuit board, I doubt it can handle more than > 1000 volts that a worst case random wire -- or a fault -- could cause > at the output of the KAT3A tuner when the K3 is producing full rated > output. But its unlikely that the KAT3A can produce full rated K3 > output because of inevitable low tuner efficiency at high VSWRs. > > __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Examining the KAT3A circuit board, I doubt it can handle more than 1000 volts that a worst case random wire -- or a fault -- could cause at the output of the KAT3A tuner when the K3 is producing full rated output. But its unlikely that the KAT3A can produce full rated K3 output because of inevitable low tuner efficiency at high VSWRs. I've never connected an antenna with a greater than 10:1 VSWR to my KAT3A tuner. I would never intentionally do that because of the stress it would could cause to the tuner components from high voltage and/or high current and inevitable poor tuner efficiency when feeding very high VSWR. Hopefully the K3's very fast acting excess VSWR detection turns down its output power before damage occurs. The K3's excess VSWR protection is very effective at preventing damage when the tuner is off. A better solution to extreme VSWR that can be caused by a truly random length antenna is to use one of the proven commercial multiband wire antennas. Just one example of a simple eight band wire antenna that definitely will not damage a K3: www.dxengineering.com/parts/pez-ef-allbandkw 73 Frank W3LPL - Original Message - From: "Walter Underwood" To: "Elecraft Reflector" Sent: Sunday, December 13, 2020 6:45:34 PM Subject: Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? I think you just proved my point. The KAT3A does not have a lower power rating for larger SWRs. That would indicate that it can handle the rated power over the entire rated SWR range. If extreme SWR at full power would exceed the component ratings, the specs would say that. This is the entire set of specs for the KAT3A: • Maximum impedance match: 10:1 SWR • Maximum power handling: 110 watts https://elecraft.com/collections/kat3a_model/products/kat3a-100w-atu I just curious why people would think that Elecraft publishes specs that their equipment does not meet. That is a pretty strong accusation. No, I didn’t check out TLW, but I have a solid understanding of transmission lines and conjugate matches, even though I only got a B- in my fields and waves class at Rice. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 12, 2020, at 11:12 PM, David Gilbert wrote: > > > Seriously?? Why do you think that Elecraft's tuners (like just about every > other one) have max power ratings that differ depending upon the SWR? For > example, for the KAT500 has a max power rating of 1000 watts into a 3:1 SWR > but only a 600 watt rating into a 10:1 SWR??? It can match both SWRs, but not > handle the same power at both. > > Did you bother to check out TLW like I suggested? > > Dave AB7E > > > > On 12/12/2020 8:59 PM, Walter Underwood wrote: >> Of course there are high voltages or currents in some tuning solutions. Why >> do people think the Elecraft ATU would not be designed to handle those? >> >> wunder >> K6WRU >> Walter Underwood >> CM87wj >> http://observer.wunderwood.org/ (my blog) >> >>> On Dec 12, 2020, at 7:36 PM, David Gilbert wrote: >>> >>> >>> A matched conditon does NOT prevent the components of the tuner from seeing >>> high voltages and/or high currents. Check out TLW ... the transmission line >>> application that comes free with the ARRL Antenna Book. Pick a load that >>> gives a high SWR and then click on the "Tuner" button for the application >>> to draw one of four different tuner configurations for you. The app will >>> tell you what the voltages across each component are, and also the power >>> loss (i.e., heating effects) in each one. >>> >>> 73, >>> Dave AB7E >>> >>> >>> >>> >>> On 12/12/2020 8:18 PM, Walter Underwood wrote: >>>> Tuning happens at low power, so transients are small. After it is matched, >>>> why would the K3 ATU not be rated for full power over the full SWR range? >>>> >>>> Other components might fail, of course. Amphenol UHF connectors are only >>>> rated for 500 V. >>>> >>>> wunder >>>> K6WRU >>>> Walter Underwood >>>> CM87wj >>> __ >>> 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 wun...@wunderwood.org >&
Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
I think you just proved my point. The KAT3A does not have a lower power rating for larger SWRs. That would indicate that it can handle the rated power over the entire rated SWR range. If extreme SWR at full power would exceed the component ratings, the specs would say that. This is the entire set of specs for the KAT3A: • Maximum impedance match: 10:1 SWR • Maximum power handling: 110 watts https://elecraft.com/collections/kat3a_model/products/kat3a-100w-atu I just curious why people would think that Elecraft publishes specs that their equipment does not meet. That is a pretty strong accusation. No, I didn’t check out TLW, but I have a solid understanding of transmission lines and conjugate matches, even though I only got a B- in my fields and waves class at Rice. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 12, 2020, at 11:12 PM, David Gilbert wrote: > > > Seriously?? Why do you think that Elecraft's tuners (like just about every > other one) have max power ratings that differ depending upon the SWR? For > example, for the KAT500 has a max power rating of 1000 watts into a 3:1 SWR > but only a 600 watt rating into a 10:1 SWR??? It can match both SWRs, but > not handle the same power at both. > > Did you bother to check out TLW like I suggested? > > Dave AB7E > > > > On 12/12/2020 8:59 PM, Walter Underwood wrote: >> Of course there are high voltages or currents in some tuning solutions. Why >> do people think the Elecraft ATU would not be designed to handle those? >> >> wunder >> K6WRU >> Walter Underwood >> CM87wj >> http://observer.wunderwood.org/ (my blog) >> >>> On Dec 12, 2020, at 7:36 PM, David Gilbert wrote: >>> >>> >>> A matched conditon does NOT prevent the components of the tuner from seeing >>> high voltages and/or high currents. Check out TLW ... the transmission >>> line application that comes free with the ARRL Antenna Book. Pick a load >>> that gives a high SWR and then click on the "Tuner" button for the >>> application to draw one of four different tuner configurations for you. >>> The app will tell you what the voltages across each component are, and also >>> the power loss (i.e., heating effects) in each one. >>> >>> 73, >>> Dave AB7E >>> >>> >>> >>> >>> On 12/12/2020 8:18 PM, Walter Underwood wrote: Tuning happens at low power, so transients are small. After it is matched, why would the K3 ATU not be rated for full power over the full SWR range? Other components might fail, of course. Amphenol UHF connectors are only rated for 500 V. wunder K6WRU Walter Underwood CM87wj >>> __ >>> 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 wun...@wunderwood.org >> __ >> 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 ab7e...@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 wun...@wunderwood.org __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Regardless of what happens to the tuner, the better the untuned match, the less power you lose in the matching network, and the more power goes out on the air. 73 Bill AE6JV On 12/13/20 at 10:02 AM, pu...@af2z.net (Drew AF2Z) wrote: But as someone else has mentioned-- choose an optimal "random" length so as to get a good match on multiple bands. --- Bill Frantz| Privacy is dead, get over | Periwinkle (408)348-7900 | it. | 150 Rivermead Rd #235 www.pwpconsult.com |- Scott McNealy (1999) | Peterborough, NH 03458 __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
The point is that protection is built into the tuner & the firmware to take care of extreme instances. As I recall, one release a few years back stated that it will handle the parting of an antenna wire while transmitting at maximum output. We can assume that a non-resonant antenna is not cause for concern. There's not much point in having an ATU if it can only be used with resonant antennas. But as someone else has mentioned-- choose an optimal "random" length so as to get a good match on multiple bands. 73, Drew AF2Z On 12/13/20 02:12, David Gilbert wrote: Seriously?? Why do you think that Elecraft's tuners (like just about every other one) have max power ratings that differ depending upon the SWR? For example, for the KAT500 has a max power rating of 1000 watts into a 3:1 SWR but only a 600 watt rating into a 10:1 SWR??? It can match both SWRs, but not handle the same power at both. Did you bother to check out TLW like I suggested? Dave AB7E On 12/12/2020 8:59 PM, Walter Underwood wrote: Of course there are high voltages or currents in some tuning solutions. Why do people think the Elecraft ATU would not be designed to handle those? wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) On Dec 12, 2020, at 7:36 PM, David Gilbert wrote: A matched conditon does NOT prevent the components of the tuner from seeing high voltages and/or high currents. Check out TLW ... the transmission line application that comes free with the ARRL Antenna Book. Pick a load that gives a high SWR and then click on the "Tuner" button for the application to draw one of four different tuner configurations for you. The app will tell you what the voltages across each component are, and also the power loss (i.e., heating effects) in each one. 73, Dave AB7E On 12/12/2020 8:18 PM, Walter Underwood wrote: Tuning happens at low power, so transients are small. After it is matched, why would the K3 ATU not be rated for full power over the full SWR range? Other components might fail, of course. Amphenol UHF connectors are only rated for 500 V. wunder K6WRU Walter Underwood CM87wj __ 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 wun...@wunderwood.org __ 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 ab7e...@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 pu...@af2z.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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Seriously?? Why do you think that Elecraft's tuners (like just about every other one) have max power ratings that differ depending upon the SWR? For example, for the KAT500 has a max power rating of 1000 watts into a 3:1 SWR but only a 600 watt rating into a 10:1 SWR??? It can match both SWRs, but not handle the same power at both. Did you bother to check out TLW like I suggested? Dave AB7E On 12/12/2020 8:59 PM, Walter Underwood wrote: Of course there are high voltages or currents in some tuning solutions. Why do people think the Elecraft ATU would not be designed to handle those? wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) On Dec 12, 2020, at 7:36 PM, David Gilbert wrote: A matched conditon does NOT prevent the components of the tuner from seeing high voltages and/or high currents. Check out TLW ... the transmission line application that comes free with the ARRL Antenna Book. Pick a load that gives a high SWR and then click on the "Tuner" button for the application to draw one of four different tuner configurations for you. The app will tell you what the voltages across each component are, and also the power loss (i.e., heating effects) in each one. 73, Dave AB7E On 12/12/2020 8:18 PM, Walter Underwood wrote: Tuning happens at low power, so transients are small. After it is matched, why would the K3 ATU not be rated for full power over the full SWR range? Other components might fail, of course. Amphenol UHF connectors are only rated for 500 V. wunder K6WRU Walter Underwood CM87wj __ 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 wun...@wunderwood.org __ 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 ab7e...@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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Hi Mike, You do have an alternative: Rather than using a random wire length, chose a wire length that produces well under 10:1 VSWR on the frequencies you intend to use. For end fed random wires, avoiding wire lengths close to multiples of 1/2 wavelength should be safe with the K3 tuner. 73 Frank W3LPL - Original Message - From: "Mister Mike" To: donov...@erols.com Cc: elecraft@mailman.qth.net Sent: Sunday, December 13, 2020 1:04:26 AM Subject: Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? That is pretty much what I thought. I will have to read the fine manual and see how the automatic tuner works. Picked up this K3 in a swap deal a while back but I am still pretty much stuck ( happily) in the Collins KWM-2/S-Line “Stone Age” so I need time and patience (lots) to figure how to use these marvelous appliance radios. In any event I have a MAC-200 made by SGC who make pretty darn good tuners which I can use but that is another box to take along if I do a road trop. 73 to all Michael, W1RC On Dec 12, 2020, at 6:37 PM, donov...@erols.com wrote: Hi Mike, Its not wise to use the K3 antenna tuner to tune a random wire. A truly random wire can easily produce VSWR greater than 10:1 which is likely to damage the K3 tuner when running at full K3 output power. Its much wiser to use an external tuner with a random wire 73 Frank W3LPL -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Mister Mike Sent: Saturday, December 12, 2020 9:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? What is the best way to do this? I am not familiar with automatic tuners. __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Of course there are high voltages or currents in some tuning solutions. Why do people think the Elecraft ATU would not be designed to handle those? wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 12, 2020, at 7:36 PM, David Gilbert wrote: > > > A matched conditon does NOT prevent the components of the tuner from seeing > high voltages and/or high currents. Check out TLW ... the transmission line > application that comes free with the ARRL Antenna Book. Pick a load that > gives a high SWR and then click on the "Tuner" button for the application to > draw one of four different tuner configurations for you. The app will tell > you what the voltages across each component are, and also the power loss > (i.e., heating effects) in each one. > > 73, > Dave AB7E > > > > > On 12/12/2020 8:18 PM, Walter Underwood wrote: >> Tuning happens at low power, so transients are small. After it is matched, >> why would the K3 ATU not be rated for full power over the full SWR range? >> >> Other components might fail, of course. Amphenol UHF connectors are only >> rated for 500 V. >> >> wunder >> K6WRU >> Walter Underwood >> CM87wj > > __ > 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 wun...@wunderwood.org __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
A matched conditon does NOT prevent the components of the tuner from seeing high voltages and/or high currents. Check out TLW ... the transmission line application that comes free with the ARRL Antenna Book. Pick a load that gives a high SWR and then click on the "Tuner" button for the application to draw one of four different tuner configurations for you. The app will tell you what the voltages across each component are, and also the power loss (i.e., heating effects) in each one. 73, Dave AB7E On 12/12/2020 8:18 PM, Walter Underwood wrote: Tuning happens at low power, so transients are small. After it is matched, why would the K3 ATU not be rated for full power over the full SWR range? Other components might fail, of course. Amphenol UHF connectors are only rated for 500 V. wunder K6WRU Walter Underwood CM87wj __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Tuning happens at low power, so transients are small. After it is matched, why would the K3 ATU not be rated for full power over the full SWR range? Other components might fail, of course. Amphenol UHF connectors are only rated for 500 V. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 12, 2020, at 5:04 PM, Mister Mike wrote: > > That is pretty much what I thought. I will have to read the fine manual and > see how the automatic tuner works. Picked up this K3 in a swap deal a while > back but I am still pretty much stuck ( happily) in the Collins KWM-2/S-Line > “Stone Age” so I need time and patience (lots) to figure how to use these > marvelous appliance radios. > > In any event I have a MAC-200 made by SGC who make pretty darn good tuners > which I can use but that is another box to take along if I do a road trop. > > 73 to all > > Michael, W1RC > >> On Dec 12, 2020, at 6:37 PM, donov...@erols.com wrote: > >> Hi Mike, >> >> Its not wise to use the K3 antenna tuner to tune a random wire. >> A truly random wire can easily produce VSWR greater than 10:1 >> which is likely to damage the K3 tuner when running at full >> K3 output power. >> >> Its much wiser to use an external tuner with a random wire >> >> 73 >> Frank >> W3LPL >> >> >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net On >> Behalf Of Mister Mike >> Sent: Saturday, December 12, 2020 9:42 AM >> To: elecraft@mailman.qth.net >> Subject: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal >> Tuner?? >> >> What is the best way to do this? I am not familiar with automatic tuners. > __ > 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 wun...@wunderwood.org __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
That is pretty much what I thought. I will have to read the fine manual and see how the automatic tuner works. Picked up this K3 in a swap deal a while back but I am still pretty much stuck ( happily) in the Collins KWM-2/S-Line “Stone Age” so I need time and patience (lots) to figure how to use these marvelous appliance radios. In any event I have a MAC-200 made by SGC who make pretty darn good tuners which I can use but that is another box to take along if I do a road trop. 73 to all Michael, W1RC > On Dec 12, 2020, at 6:37 PM, donov...@erols.com wrote: > Hi Mike, > > Its not wise to use the K3 antenna tuner to tune a random wire. > A truly random wire can easily produce VSWR greater than 10:1 > which is likely to damage the K3 tuner when running at full > K3 output power. > > Its much wiser to use an external tuner with a random wire > > 73 > Frank > W3LPL > > > > -Original Message- > From: elecraft-boun...@mailman.qth.net On > Behalf Of Mister Mike > Sent: Saturday, December 12, 2020 9:42 AM > To: elecraft@mailman.qth.net > Subject: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? > > What is the best way to do this? I am not familiar with automatic tuners. __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Hi Mike, Its not wise to use the K3 antenna tuner to tune a random wire. A truly random wire can easily produce VSWR greater than 10:1 which is likely to damage the K3 tuner when running at full K3 output power. Its much wiser to use an external tuner with a random wire 73 Frank W3LPL -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Mister Mike Sent: Saturday, December 12, 2020 9:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? What is the best way to do this? I am not familiar with automatic tuners. TIA, Michael, W1RC __ 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 gthorn...@thorntonmostullaw.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 donov...@starpower.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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Very occasionally the K3 ATU will not find a good match and you may be able to do better by setting the tuning elements yourself. That is the case for my 70' endfed wire on 160m. The ATU will match it on all other bands though. To tune the elements manually select "LC Set" in the Config:KAT3 menu. 73, Drew AF2Z On 12/12/20 12:55, Walter Underwood wrote: A random-length wire is usually chosen to avoid a half-wavelength on the frequencies you’ll be using. A more accurate term is non-resonant end-fed antenna. Avoiding half-wavelengths means the impedance will not be 5000 Ω or greater, but it will be pretty high. Or low. The SWR on the feed line will be large and a high impedance feed point is pretty sensitive to surrounding objects (capacitance). So: 1. Keep the coax short and low loss. 2. At the antenna, connect some sort of counterpoise or RF ground to the shield of the coax. This can be a ground rod, a radial system, or a wire laying on the ground. If you don’t do that, the RF ground will be the coax and everything connected to it, including your K3. 3. After that, tell the ATU to tune it and wait for it to find a solution. 4. If it won’t match, change something. Maybe the length of the wire, maybe the position, maybe the counterpoise. If this is a long-term setup, a common mode choke near the rig is a good idea. Even with a counterpoise, some of that RF energy is going to be on the shield. For field deployments with the KX3, I run with no feed line at all. The antenna wire and counterpoise wire are connected directly to the KX3 with a double binding post adapter. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) On Dec 12, 2020, at 9:41 AM, Mister Mike wrote: What is the best way to do this? I am not familiar with automatic tuners. TIA, Michael, W1RC __ 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 wun...@wunderwood.org __ 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 pu...@af2z.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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
You might take a look at the SGC company website. They make excellent autotuners designed to be mounted outdoors at the antenna. The site includes a number of guide articles and manuals with a wealth of information. These tuners are fully automatic in that when you first transmit on a frequency the tuner automatically tunes and puts the setting for that frequency in memory. When operating these with the K3 you use the tune button (long press on the xmit key) and watch the SWR go down as the unit tunes. -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Mister Mike Sent: Saturday, December 12, 2020 9:42 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner?? What is the best way to do this? I am not familiar with automatic tuners. TIA, Michael, W1RC __ 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 gthorn...@thorntonmostullaw.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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
Mr. Mike, Be sure you have the KAT3 internal ATU "enabled" and not bypassed, be sure the proper antenna is selected (ANT 1 or ANT 2) for your random wire, and press (momentary) the ATU TUNE button. The relays will clatter a bit, and you'll see the displayed SWR ratcheting down, maybe up for short time, as a tuning solution is searched. If the SWR isn't low enough for your tastes, press the ATU TUNE button again within 5 seconds of the conclusion of the previous attempt's end, and the ATU will try again, often with slightly improved result. Don't be surprised if you experience RF gremlins in your shack with a random length wire without a counterpoise. Mike, K8CN (hoping to be back at NEAR-Fest next year!) -- Sent from: http://elecraft.365791.n2.nabble.com/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
A random-length wire is usually chosen to avoid a half-wavelength on the frequencies you’ll be using. A more accurate term is non-resonant end-fed antenna. Avoiding half-wavelengths means the impedance will not be 5000 Ω or greater, but it will be pretty high. Or low. The SWR on the feed line will be large and a high impedance feed point is pretty sensitive to surrounding objects (capacitance). So: 1. Keep the coax short and low loss. 2. At the antenna, connect some sort of counterpoise or RF ground to the shield of the coax. This can be a ground rod, a radial system, or a wire laying on the ground. If you don’t do that, the RF ground will be the coax and everything connected to it, including your K3. 3. After that, tell the ATU to tune it and wait for it to find a solution. 4. If it won’t match, change something. Maybe the length of the wire, maybe the position, maybe the counterpoise. If this is a long-term setup, a common mode choke near the rig is a good idea. Even with a counterpoise, some of that RF energy is going to be on the shield. For field deployments with the KX3, I run with no feed line at all. The antenna wire and counterpoise wire are connected directly to the KX3 with a double binding post adapter. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Dec 12, 2020, at 9:41 AM, Mister Mike wrote: > > What is the best way to do this? I am not familiar with automatic tuners. > > TIA, > > Michael, W1RC > __ > 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 wun...@wunderwood.org __ 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] Tuning Random-Length Wire Antenna with K3 Internal Tuner??
What is the best way to do this? I am not familiar with automatic tuners. TIA, Michael, W1RC __ 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
