[Elecraft] Suggestions needed - antenna to tuner
I could use a little advice My present setup is; KX3 > KPA100 (w/ ATU) > MFJ Balanced line tuner > ladder line fed 80m Inv 'V' I run this with the ATU disabled and then manually tune. Obviously this is time consuming and makes band switching a pain so I am considering removing the MFJ from the chain and start using the ATU. Also I plan to add a KPA/KAT500 in the near future and my MJF tops out at 300w so I has to go anway. The questions are... 1) Should I do it? or will I see a significant performance decrease? 2) If I do - How should I make the ladder to coax conversion? I think I need a "tuner balun"? 73 Alan KN4BBC __ 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] Suggestions needed - antenna to tuner
Continue with the balanced line to the dipole ~ mine is spaced 10cm #
14 wire {home-assembled}
and use the Johnson Match-Box = it is a balanced line output tuner ~ NO
need for a current balun
or similar, like a Z-Match . . . Reference: REFLECTIONS by Maxwell
Cheers, Jan K1ND
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Re: [Elecraft] Suggestions needed - antenna to tuner
MORE Info As is I can work 80-10. Some bands are better then others but I can work them all with an SWR in the 1:1 to 1.3:1 range.The fed line is 450 window. The dipole is center fed. On Mon, Feb 12, 2018 at 9:26 AM, Alan Lambert wrote: > I could use a little advice > > My present setup is; > KX3 > KPA100 (w/ ATU) > MFJ Balanced line tuner > ladder line fed > 80m Inv 'V' > > I run this with the ATU disabled and then manually tune. Obviously > this is time consuming and makes band switching a pain so I am > considering removing the MFJ from the chain and start using the ATU. > Also I plan to add a KPA/KAT500 in the near future and my MJF tops out > at 300w so I has to go anway. > > > The questions are... > > 1) Should I do it? or will I see a significant performance decrease? > > 2) If I do - How should I make the ladder to coax conversion? I > think I need a "tuner balun"? > > 73 > Alan > KN4BBC __ 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] Suggestions needed - antenna to tuner
Alan - I am pleased with results I have gotten with units from BALUN DESIGNS. Their 1161 & 1171 models are possible choices. I know some folks would rather spend less and build their own, but if that is not your preference, then look at these models. Best of luck. 73 de Dave - K9FN On Mon, Feb 12, 2018 at 10:20 AM, Alan Lambert wrote: > MORE Info > > As is I can work 80-10. Some bands are better then others but I can > work them all with an SWR in the 1:1 to 1.3:1 range.The fed line > is 450 window. The dipole is center fed. > > On Mon, Feb 12, 2018 at 9:26 AM, Alan Lambert > wrote: > > I could use a little advice > > > > My present setup is; > > KX3 > KPA100 (w/ ATU) > MFJ Balanced line tuner > ladder line fed > > 80m Inv 'V' > > > > I run this with the ATU disabled and then manually tune. Obviously > > this is time consuming and makes band switching a pain so I am > > considering removing the MFJ from the chain and start using the ATU. > > Also I plan to add a KPA/KAT500 in the near future and my MJF tops out > > at 300w so I has to go anway. > > > > > > The questions are... > > > > 1) Should I do it? or will I see a significant performance decrease? > > > > 2) If I do - How should I make the ladder to coax conversion? I > > think I need a "tuner balun"? > > > > 73 > > Alan > > KN4BBC > __ > 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
Re: [Elecraft] Suggestions needed - antenna to tuner
I've used balanced line systems and tuners and baluns for years. In general the 135 ft center fed wire with your choice of balanced line, I use the vinyl covered 450 line from The Wireman, will work quite well. I bring the line from the feed point of the antenna all the way to the operating position where it terminated into the 1:1 current balun. Balanced line of this type is not near as difficult to use as many will allude. Just use common sense. Be sure to use lightning protection on the line before it enters the house. Regarding baluns, keep in mind that one is not "matching the line" i.e. 450 ohms but the overall load Z. Hence the better choice is the 1:1 current balun and not the 4:1 as many seem to believe. Also, understand that the design and rating of baluns is based on a matched operating condition on both sides of the balun. The 135 ft center fed wire with balanced feed is in most cases far from matched. Thus the balun should be rated for much higher power than one would ever expect to run. In my case, for legal limit power, my balun is rated at 10KW. I do use BALUN DESIGNS products for my applications. Be sure you select a balun which is designed to be used with a tuner as the voltage / current ratings will be different than those for matched applications. What is a matched application for a balun?. A good example is a folded dipole made of and fed with balanced line. Typically the folded dipole Z is about 300 ohms regardless of line impedance. However, due to reasonable proximity to the earth, the impedance is more like 200 to 250 ohms. Hence a 4:1 balun is the ideal choice providing an unbalanced feed to the transmitter of about 50 ohms. Here is a good source for real world applications and performance of baluns. http://www.dj0ip.de/balun-stuff/ 73 Bob, K4TAX On 2/12/2018 9:29 AM, David Bunte wrote: Alan - I am pleased with results I have gotten with units from BALUN DESIGNS. Their 1161 & 1171 models are possible choices. I know some folks would rather spend less and build their own, but if that is not your preference, then look at these models. Best of luck. 73 de Dave - K9FN On Mon, Feb 12, 2018 at 10:20 AM, Alan Lambert wrote: MORE Info As is I can work 80-10. Some bands are better then others but I can work them all with an SWR in the 1:1 to 1.3:1 range.The fed line is 450 window. The dipole is center fed. On Mon, Feb 12, 2018 at 9:26 AM, Alan Lambert wrote: I could use a little advice My present setup is; KX3 > KPA100 (w/ ATU) > MFJ Balanced line tuner > ladder line fed 80m Inv 'V' I run this with the ATU disabled and then manually tune. Obviously this is time consuming and makes band switching a pain so I am considering removing the MFJ from the chain and start using the ATU. Also I plan to add a KPA/KAT500 in the near future and my MJF tops out at 300w so I has to go anway. The questions are... 1) Should I do it? or will I see a significant performance decrease? 2) If I do - How should I make the ladder to coax conversion? I think I need a "tuner balun"? 73 Alan KN4BBC __ 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 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] Suggestions needed - antenna to tuner
Alan, Good questions. The Elecraft tuners can not be beat for what they can tune, so the only real issue is how to transition to coax from open wire/ladder line. Probably, the easiest is to use a 4:1 current balun to make the transition. I would go with one that is rated at least 3KW. Why so heavy? The answer is core heating when running with a high SWR; this is more of a design "safety" issue. And, the current balun will stay balanced better than a voltage balun when presented a high SWR. I use a variant of this here in my station, meaning the antenna is slightly different. It works great with no problems and I can use my antenna 80-10 meters. DXengineering and Balun Designs make good baluns as I'm sure there are others, but I know these work. One last thought. Make the transition as close to where your egress point is. If you have a fairly lengthy transmission line run, you will be using the lowest loss line for as far as you can go and then transition. I would use a very low loss cable from the balun to the tuner, something like LMR-400. 73, Barry K3NDM -- Original Message -- From: "Alan Lambert" To: elecraft@mailman.qth.net Sent: 2/12/2018 9:26:40 AM Subject: [Elecraft] Suggestions needed - antenna to tuner I could use a little advice My present setup is; KX3 > KPA100 (w/ ATU) > MFJ Balanced line tuner > ladder line fed 80m Inv 'V' I run this with the ATU disabled and then manually tune. Obviously this is time consuming and makes band switching a pain so I am considering removing the MFJ from the chain and start using the ATU. Also I plan to add a KPA/KAT500 in the near future and my MJF tops out at 300w so I has to go anway. The questions are... 1) Should I do it? or will I see a significant performance decrease? 2) If I do - How should I make the ladder to coax conversion? I think I need a "tuner balun"? 73 Alan KN4BBC __ 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 k3...@comcast.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] Suggestions needed - antenna to tuner
I replaced my Johnson Matchbox with a Balun Designs tuner balun. The biggest benefit is that the K3 ATU remembers the settings from band to band so the QSY is very rapid. I love watching the DX spots come rolling through on my N3FJP logging program and clicking on them to QSY to that frequency and not have to tune up again. I use it on 80 through 6 meters with an 80m doublet fed with KW ladder line (300 ohm). My recommendation is to keep the piece of coax from the balun to the rig as short as possible. This is to minimize loss since that line will most likely be highly mis-matched on most bands. There was a QST article not that long ago which detailed the losses in that situation and I was surprised at how high they were. I once had an MFJ balanced RF Ammeter and made measurements of the JMB vs. the balun and they compared favorably. DJ0IP (referenced earlier) has kindly put those measurements on his website. (This is in the FWIW category!) I have not tried to substitute the tuner balun with another type but that might be a future experiment. 73, John W2XS -- 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] Suggestions needed - antenna to tuner
I have not seen any of their products, but a post on their website indicates that they do not understand how common mode chokes work. The result is that they sell stuff that won't burn up, but it won't do anything useful either. 73, Jim K9YC On 2/12/2018 7:29 AM, David Bunte wrote: I am pleased with results I have gotten with units from BALUN DESIGNS. __ 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] Suggestions needed - antenna to tuner
I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m doublet. It works fantastic on 80-20, but will not tune better than about 2:1 on 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing I've tried works. I'm wondering if it is simply the tuning range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as I have only a couple feet of coax between the tuner and the balun, thus minimizing SWR-related feedline loss. Any suggestions for how to get it to tune on 17? 73 Chris - K1AY Punta Gorda, FL On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: > I replaced my Johnson Matchbox with a Balun Designs tuner balun. The > biggest > benefit is that the K3 ATU remembers the settings from band to band so the > QSY is very rapid. I love watching the DX spots come rolling through on my > N3FJP logging program and clicking on them to QSY to that frequency and not > have to tune up again. I use it on 80 through 6 meters with an 80m doublet > fed with KW ladder line (300 ohm). > > My recommendation is to keep the piece of coax from the balun to the rig as > short as possible. This is to minimize loss since that line will most > likely be highly mis-matched on most bands. There was a QST article not > that > long ago which detailed the losses in that situation and I was surprised at > how high they were. > > I once had an MFJ balanced RF Ammeter and made measurements of the JMB vs. > the balun and they compared favorably. DJ0IP (referenced earlier) has > kindly put those measurements on his website. (This is in the FWIW > category!) > > I have not tried to substitute the tuner balun with another type but that > might be a future experiment. > > 73, John W2XS > > > > -- > 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 challi...@gmail.com > -- Life is like Linux - it never stands still. __ 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] Suggestions needed - antenna to tuner
Chris; Add or remove about 6 ft of the open wire line. See if this helps the 17M issue. I personally don't like the idea of using a 4:1 balun and much prefer a 1:1 current balun. With the 4:1, without measuring the Z on the coax side, it may be the Z presented to the tuner is very low and thus outside the range of the tuner. Additionally, it is most likely with almost every ATU, the greatest loss occurs when the Z is low to very low. Hence my reason for using a 1:1 and not a 4:1. 73 Bob, K4TAX On 2/13/2018 7:55 AM, Chris Hallinan wrote: I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m doublet. It works fantastic on 80-20, but will not tune better than about 2:1 on 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing I've tried works. I'm wondering if it is simply the tuning range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as I have only a couple feet of coax between the tuner and the balun, thus minimizing SWR-related feedline loss. Any suggestions for how to get it to tune on 17? 73 Chris - K1AY Punta Gorda, FL On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: I replaced my Johnson Matchbox with a Balun Designs tuner balun. The biggest benefit is that the K3 ATU remembers the settings from band to band so the QSY is very rapid. I love watching the DX spots come rolling through on my N3FJP logging program and clicking on them to QSY to that frequency and not have to tune up again. I use it on 80 through 6 meters with an 80m doublet fed with KW ladder line (300 ohm). My recommendation is to keep the piece of coax from the balun to the rig as short as possible. This is to minimize loss since that line will most likely be highly mis-matched on most bands. There was a QST article not that long ago which detailed the losses in that situation and I was surprised at how high they were. I once had an MFJ balanced RF Ammeter and made measurements of the JMB vs. the balun and they compared favorably. DJ0IP (referenced earlier) has kindly put those measurements on his website. (This is in the FWIW category!) I have not tried to substitute the tuner balun with another type but that might be a future experiment. 73, John W2XS -- 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 challi...@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] Suggestions needed - antenna to tuner
Thanks, Bob. I'll do just that when I get a chance. And I might just try the 1:1 also! I have an Array Solutions analyzer, been meaning to scan it to see exactly what the tuner sees. All of this requires a ladder and some creative juggling of tools/laptop etc. ;) 73 Chris On Tue, Feb 13, 2018 at 9:04 AM, Bob McGraw K4TAX wrote: > Chris; > > Add or remove about 6 ft of the open wire line. See if this helps the 17M > issue. > > I personally don't like the idea of using a 4:1 balun and much prefer a > 1:1 current balun. With the 4:1, without measuring the Z on the coax side, > it may be the Z presented to the tuner is very low and thus outside the > range of the tuner. Additionally, it is most likely with almost every > ATU, the greatest loss occurs when the Z is low to very low. Hence my > reason for using a 1:1 and not a 4:1. > > 73 > > Bob, K4TAX > > > > On 2/13/2018 7:55 AM, Chris Hallinan wrote: > >> I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner >> mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m >> doublet. >> >> It works fantastic on 80-20, but will not tune better than about 2:1 on >> 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing >> I've tried works. I'm wondering if it is simply the tuning >> range/resolution of the MFJ-994BRT? I like the idea of remote mounting, >> as >> I have only a couple feet of coax between the tuner and the balun, thus >> minimizing SWR-related feedline loss. >> >> Any suggestions for how to get it to tune on 17? >> >> 73 >> Chris - K1AY >> Punta Gorda, FL >> >> >> On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: >> >> I replaced my Johnson Matchbox with a Balun Designs tuner balun. The >>> biggest >>> benefit is that the K3 ATU remembers the settings from band to band so >>> the >>> QSY is very rapid. I love watching the DX spots come rolling through on >>> my >>> N3FJP logging program and clicking on them to QSY to that frequency and >>> not >>> have to tune up again. I use it on 80 through 6 meters with an 80m >>> doublet >>> fed with KW ladder line (300 ohm). >>> >>> My recommendation is to keep the piece of coax from the balun to the rig >>> as >>> short as possible. This is to minimize loss since that line will most >>> likely be highly mis-matched on most bands. There was a QST article not >>> that >>> long ago which detailed the losses in that situation and I was surprised >>> at >>> how high they were. >>> >>> I once had an MFJ balanced RF Ammeter and made measurements of the JMB >>> vs. >>> the balun and they compared favorably. DJ0IP (referenced earlier) has >>> kindly put those measurements on his website. (This is in the FWIW >>> category!) >>> >>> I have not tried to substitute the tuner balun with another type but that >>> might be a future experiment. >>> >>> 73, John W2XS >>> >>> >>> >>> -- >>> 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 challi...@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 challi...@gmail.com > -- Life is like Linux - it never stands still. __ 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] Suggestions needed - antenna to tuner
Chris, Try a 1:1 balun instead of the 4:1. You are matching the impedance seen at the shack end of the feedline, and that can vary from very low to very high. The impedance you have to match is NOT the characteristic impedance of the feedline. The 600 ohm line simply acts as an impedance transformer. The only time you will see a 600 ohm impedance at the shack end of that feedline is when the far end is terminated by 600 ohms, and I suggest that is not true of the feedpoint impedance at the antenna. 73, Don W3FPR On 2/13/2018 8:55 AM, Chris Hallinan wrote: I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m doublet. It works fantastic on 80-20, but will not tune better than about 2:1 on 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing I've tried works. I'm wondering if it is simply the tuning range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as I have only a couple feet of coax between the tuner and the balun, thus minimizing SWR-related feedline loss. __ 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] Suggestions needed - antenna to tuner
Thanks, Don, Yes I understand the basics - the doublet is not typically used in a "matched" configuration, thus the need for the tuner. If I understand correctly, it can present from very low to very high impedances to the tuner. I will try a 1:1 and/or adding some wire length. Also, as I mentioned in my previous post, I've been wanting to get up on the ladder and scan it with my Array Solutions antenna analyzer to see what it really presents to the tuner. That may help me understand what I need to do. 73, Chris - K1AY On Tue, Feb 13, 2018 at 9:13 AM, Don Wilhelm wrote: > Chris, > > Try a 1:1 balun instead of the 4:1. You are matching the impedance seen > at the shack end of the feedline, and that can vary from very low to very > high. > The impedance you have to match is NOT the characteristic impedance of the > feedline. The 600 ohm line simply acts as an impedance transformer. > The only time you will see a 600 ohm impedance at the shack end of that > feedline is when the far end is terminated by 600 ohms, and I suggest that > is not true of the feedpoint impedance at the antenna. > > 73, > Don W3FPR > > > On 2/13/2018 8:55 AM, Chris Hallinan wrote: > >> I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner >> mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m >> doublet. >> >> It works fantastic on 80-20, but will not tune better than about 2:1 on >> 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing >> I've tried works. I'm wondering if it is simply the tuning >> range/resolution of the MFJ-994BRT? I like the idea of remote mounting, >> as >> I have only a couple feet of coax between the tuner and the balun, thus >> minimizing SWR-related feedline loss. >> > -- Life is like Linux - it never stands still. __ 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] Suggestions needed - antenna to tuner
Have you tried adding some additional length to the 600 ohm feedline? I originally couldn't perfectly match 30 meters with the Johnson Matchbox and added about 15 or 18 feet IIRC. That brought 30m into range and didn't mess up the other bands too much. Since your worst band is 17m, you might need only a few feet (5 or 10 is a swag). 73, John W2XS -- 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] Suggestions needed - antenna to tuner
I was thinking of a similar remote setup, wondering which remote autotuner is recommended? Thanks, Frank w4tg On Feb 13, 2018 8:56 AM, "Chris Hallinan" wrote: > I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner > mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m > doublet. > > It works fantastic on 80-20, but will not tune better than about 2:1 on > 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing > I've tried works. I'm wondering if it is simply the tuning > range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as > I have only a couple feet of coax between the tuner and the balun, thus > minimizing SWR-related feedline loss. > > Any suggestions for how to get it to tune on 17? > > 73 > Chris - K1AY > Punta Gorda, FL > > > On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: > > > I replaced my Johnson Matchbox with a Balun Designs tuner balun. The > > biggest > > benefit is that the K3 ATU remembers the settings from band to band so > the > > QSY is very rapid. I love watching the DX spots come rolling through on > my > > N3FJP logging program and clicking on them to QSY to that frequency and > not > > have to tune up again. I use it on 80 through 6 meters with an 80m > doublet > > fed with KW ladder line (300 ohm). > > > > My recommendation is to keep the piece of coax from the balun to the rig > as > > short as possible. This is to minimize loss since that line will most > > likely be highly mis-matched on most bands. There was a QST article not > > that > > long ago which detailed the losses in that situation and I was surprised > at > > how high they were. > > > > I once had an MFJ balanced RF Ammeter and made measurements of the JMB > vs. > > the balun and they compared favorably. DJ0IP (referenced earlier) has > > kindly put those measurements on his website. (This is in the FWIW > > category!) > > > > I have not tried to substitute the tuner balun with another type but that > > might be a future experiment. > > > > 73, John W2XS > > > > > > > > -- > > 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 challi...@gmail.com > > > > > > -- > Life is like Linux - it never stands still. > __ > 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 fst...@ieee.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] Suggestions needed - antenna to tuner
Chris, If all else fails, cheat. Probably the very simplest thing you can do is mount an 17 meter element in parallel to the 80 meter element. It will be cheaper and no less efficient. 73, Barry K3NDM -- Original Message -- From: "Chris Hallinan" To: "John W2XS" Cc: "" Sent: 2/13/2018 8:55:23 AM Subject: Re: [Elecraft] Suggestions needed - antenna to tuner I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m doublet. It works fantastic on 80-20, but will not tune better than about 2:1 on 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing I've tried works. I'm wondering if it is simply the tuning range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as I have only a couple feet of coax between the tuner and the balun, thus minimizing SWR-related feedline loss. Any suggestions for how to get it to tune on 17? 73 Chris - K1AY Punta Gorda, FL On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: I replaced my Johnson Matchbox with a Balun Designs tuner balun. The biggest benefit is that the K3 ATU remembers the settings from band to band so the QSY is very rapid. I love watching the DX spots come rolling through on my N3FJP logging program and clicking on them to QSY to that frequency and not have to tune up again. I use it on 80 through 6 meters with an 80m doublet fed with KW ladder line (300 ohm). My recommendation is to keep the piece of coax from the balun to the rig as short as possible. This is to minimize loss since that line will most likely be highly mis-matched on most bands. There was a QST article not that long ago which detailed the losses in that situation and I was surprised at how high they were. I once had an MFJ balanced RF Ammeter and made measurements of the JMB vs. the balun and they compared favorably. DJ0IP (referenced earlier) has kindly put those measurements on his website. (This is in the FWIW category!) I have not tried to substitute the tuner balun with another type but that might be a future experiment. 73, John W2XS -- 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 challi...@gmail.com -- Life is like Linux - it never stands still. __ 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 k3...@comcast.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] Suggestions needed - antenna to tuner
I have been using MFJ tuners outside (MFJ-927) on a 43' vertical in southwest Florida for many years. The only complaint I have is that they don't get along with thunderstorms. I've probably gone through half dozen of these over the years. However, it's worth it to me because when they work, they work well. Outside in Florida sun and summer rains and salt air is probably one of the most hostile environments for any electronics. And I don't protect them in any way so I'm amazed they work as long as they do. The only mod I make is to replace the ground lug with stainless steel hardware. When there is a threat of lightning, I ground the antenna (I have a large wing nut for that) and disconnect the tuner. If I forget, I might have to buy a new one ;) I love the idea of remote tuners - avoids the losses associated with coax and high SWR. 73, Chris On Tue, Feb 13, 2018 at 10:55 AM, Frank Stein wrote: > I was thinking of a similar remote setup, wondering which remote autotuner > is recommended? > Thanks, > Frank w4tg > > On Feb 13, 2018 8:56 AM, "Chris Hallinan" wrote: > >> I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner >> mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m >> doublet. >> >> It works fantastic on 80-20, but will not tune better than about 2:1 on >> 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing >> I've tried works. I'm wondering if it is simply the tuning >> range/resolution of the MFJ-994BRT? I like the idea of remote mounting, >> as >> I have only a couple feet of coax between the tuner and the balun, thus >> minimizing SWR-related feedline loss. >> >> Any suggestions for how to get it to tune on 17? >> >> 73 >> Chris - K1AY >> Punta Gorda, FL >> >> >> On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: >> >> > I replaced my Johnson Matchbox with a Balun Designs tuner balun. The >> > biggest >> > benefit is that the K3 ATU remembers the settings from band to band so >> the >> > QSY is very rapid. I love watching the DX spots come rolling through on >> my >> > N3FJP logging program and clicking on them to QSY to that frequency and >> not >> > have to tune up again. I use it on 80 through 6 meters with an 80m >> doublet >> > fed with KW ladder line (300 ohm). >> > >> > My recommendation is to keep the piece of coax from the balun to the >> rig as >> > short as possible. This is to minimize loss since that line will most >> > likely be highly mis-matched on most bands. There was a QST article not >> > that >> > long ago which detailed the losses in that situation and I was >> surprised at >> > how high they were. >> > >> > I once had an MFJ balanced RF Ammeter and made measurements of the JMB >> vs. >> > the balun and they compared favorably. DJ0IP (referenced earlier) has >> > kindly put those measurements on his website. (This is in the FWIW >> > category!) >> > >> > I have not tried to substitute the tuner balun with another type but >> that >> > might be a future experiment. >> > >> > 73, John W2XS >> > >> > >> > >> > -- >> > 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 challi...@gmail.com >> > >> >> >> >> -- >> Life is like Linux - it never stands still. >> __ >> 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 fst...@ieee.org >> > -- Life is like Linux - it never stands still. __ 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] Suggestions needed - antenna to tuner
Why not ground the antenna and feed it as a Unipole? Most AM BC stations are doing that these days. They also use a remote tuner, although it is usually a fixed network as they only use one frequency. That way the reflected power on the line is nil. 73 Bob, K4TAX On 2/13/2018 12:29 PM, Chris Hallinan wrote: I have been using MFJ tuners outside (MFJ-927) on a 43' vertical in southwest Florida for many years. The only complaint I have is that they don't get along with thunderstorms. I've probably gone through half dozen of these over the years. However, it's worth it to me because when they work, they work well. Outside in Florida sun and summer rains and salt air is probably one of the most hostile environments for any electronics. And I don't protect them in any way so I'm amazed they work as long as they do. The only mod I make is to replace the ground lug with stainless steel hardware. When there is a threat of lightning, I ground the antenna (I have a large wing nut for that) and disconnect the tuner. If I forget, I might have to buy a new one ;) I love the idea of remote tuners - avoids the losses associated with coax and high SWR. 73, Chris On Tue, Feb 13, 2018 at 10:55 AM, Frank Stein wrote: I was thinking of a similar remote setup, wondering which remote autotuner is recommended? Thanks, Frank w4tg On Feb 13, 2018 8:56 AM, "Chris Hallinan" wrote: I have a very similar setup. K3 -> KPA500 -> MFJ 994BRT 600W autotuner mounted remote -> Balun Designs 4:1 -> 600 Ohm open wire line to 80 m doublet. It works fantastic on 80-20, but will not tune better than about 2:1 on 17. I cannot use the KPA500 on 17 because the SWR is too high. Nothing I've tried works. I'm wondering if it is simply the tuning range/resolution of the MFJ-994BRT? I like the idea of remote mounting, as I have only a couple feet of coax between the tuner and the balun, thus minimizing SWR-related feedline loss. Any suggestions for how to get it to tune on 17? 73 Chris - K1AY Punta Gorda, FL On Mon, Feb 12, 2018 at 12:16 PM, John W2XS wrote: I replaced my Johnson Matchbox with a Balun Designs tuner balun. The biggest benefit is that the K3 ATU remembers the settings from band to band so the QSY is very rapid. I love watching the DX spots come rolling through on my N3FJP logging program and clicking on them to QSY to that frequency and not have to tune up again. I use it on 80 through 6 meters with an 80m doublet fed with KW ladder line (300 ohm). My recommendation is to keep the piece of coax from the balun to the rig as short as possible. This is to minimize loss since that line will most likely be highly mis-matched on most bands. There was a QST article not that long ago which detailed the losses in that situation and I was surprised at how high they were. I once had an MFJ balanced RF Ammeter and made measurements of the JMB vs. the balun and they compared favorably. DJ0IP (referenced earlier) has kindly put those measurements on his website. (This is in the FWIW category!) I have not tried to substitute the tuner balun with another type but that might be a future experiment. 73, John W2XS -- 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 challi...@gmail.com -- Life is like Linux - it never stands still. __ 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 fst...@ieee.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
