K3S Proper Grounding
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I'm wondering if the RFI is primarily due to the condition of the coax?
If a tuner is located at the rig-side of the coax, and the coax is at high SWR, it could possibly be a cause for coax radiation. A test might confirm that. Perhaps you could find a spot on 40m where the SWR is null, and no tuner is needed. If, at that point your RFI is significantly reduced, I would try feeding the antenna with twin-lead to a matching network located on the roof. That way, the coax would always be functioning as designed. In that case, a common mode choke at the load-end of the coax might also help to further reduce coax shield radiation. Something to consider. Hope you find the fix!! :-] N1BBR -- [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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On Mon,9/28/2015 9:35 AM, dw wrote:
> If a tuner is located at the rig-side of the coax, and the coax is at > high SWR, it could possibly be a cause for coax radiation. It doesn't work that way. Radiation from coax is the result of IMBALANCE in the antenna. A ferrite common mode choke at the feedpoint can fix that. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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What I don't understand is my previous radio didn't affect the TV as far as I know (xyl never complained) so it has me perplexed because the radio shouldn't matter. As far as the buckmaster ocf, it uses a current transformer (auto-transformer )to balance the antenna and match the impedance.
Jer On September 28, 2015 1:37:16 PM EDT, Jim Brown <[hidden email]> wrote: >On Mon,9/28/2015 9:35 AM, dw wrote: >> If a tuner is located at the rig-side of the coax, and the coax is at >> high SWR, it could possibly be a cause for coax radiation. > >It doesn't work that way. > >Radiation from coax is the result of IMBALANCE in the antenna. A >ferrite >common mode choke at the feedpoint can fix that. > >73, Jim K9YC >______________________________________________________________ >Elecraft mailing list >Home: http://mailman.qth.net/mailman/listinfo/elecraft >Help: http://mailman.qth.net/mmfaq.htm >Post: mailto:[hidden email] > >This list hosted by: http://www.qsl.net >Please help support this email list: http://www.qsl.net/donate.html >Message delivered to [hidden email] -- Sent from my Android device with K-9 Mail. Please excuse my brevity. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Yes the Buckmaster does use a current transformer however that method
does not provide much if any common mode rejection. As to why one radio does it and one radio does not, something is different in your system. Make sure each piece of equipment is tied {bonded} to a common point for your station. In my case, I use the power supply ground terminal as the common point. Also, since you have swapped radios around, highly suspicious would be coax jumper cable being defective or a PL-259 not being tight. I always snug my PL-259's with a pair of 4" Channel Lock pliers. With some brands and manufacture of connectors, finger tight is not good enough. 73 Bob, K4TAX On 9/30/2015 2:51 PM, Jerry Moore wrote: > What I don't understand is my previous radio didn't affect the TV as far as I know (xyl never complained) so it has me perplexed because the radio shouldn't matter. As far as the buckmaster ocf, it uses a current transformer (auto-transformer )to balance the antenna and match the impedance. > Jer ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Jerry Moore
On Wed,9/30/2015 12:51 PM, Jerry Moore wrote:
> What I don't understand is my previous radio didn't affect the TV as > far as I know (xyl never complained) so it has me perplexed because > the radio shouldn't matter. Right. But there may be some difference in where the transmitter's chassis was connected. When there's common mode current on a feedline, that connection becomes part of the antenna. > As far as the buckmaster ocf, it uses a current transformer > (auto-transformer )to balance the antenna and match the impedance. Don't believe everything you read! OCF antennas are notorious for putting common mode current on the feedline. Study http://k9yc.com/CoaxChokesPPT.pdf and http://k9yc.com/RFI-Ham.pdf 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Jerry Moore
I think we are drifting off topic, my apologies, but if you are considering an
ocf dipole you can only prevent common mode currents by use of a double wound balun, ie 2 separately made chokes connected together as a 4:1. A single core version does not properly cancel the common mode current that results in unwanted radiation from your coax feeder and can make your equipment live to rf. A huge amount of work has been done on this subject by DJ0IP and I suggest you look at his site http://www.dj0ip.de/balun-stuff/ is a good place to start. The proof of the pudding is in the eating and I have not seen anyone do real world measurements like he has on real aerials. David G3UNA > > On 30 September 2015 at 20:51 Jerry Moore <[hidden email]> wrote: > > > What I don't understand is my previous radio didn't affect the TV as far > as I know (xyl never complained) so it has me perplexed because the radio > shouldn't matter. As far as the buckmaster ocf, it uses a current transformer > (auto-transformer )to balance the antenna and match the impedance. > Jer > > On September 28, 2015 1:37:16 PM EDT, Jim Brown > <[hidden email]> wrote: > >On Mon,9/28/2015 9:35 AM, dw wrote: > >> If a tuner is located at the rig-side of the coax, and the coax is at > >> high SWR, it could possibly be a cause for coax radiation. > > > >It doesn't work that way. > > > >Radiation from coax is the result of IMBALANCE in the antenna. A > >ferrite > >common mode choke at the feedpoint can fix that. > > > >73, Jim K9YC > >______________________________________________________________ > >Elecraft mailing list > >Home: http://mailman.qth.net/mailman/listinfo/elecraft > >Help: http://mailman.qth.net/mmfaq.htm > >Post: mailto:[hidden email] > > > >This list hosted by: http://www.qsl.net > >Please help support this email list: http://www.qsl.net/donate.html > >Message delivered to [hidden email] > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Good information David. I also Have a 80m OCF
http://www.slickpic.com/users/GeneGabry/albums/N9TFHamStationPhotos/?wallpap er <http://www.slickpic.com/users/GeneGabry/albums/N9TFHamStationPhotos/?wallpa per&viewer#8644290> &viewer#8644290 and choosing the correct balun and RF choke is paramount. I went with the (W2FMI design) Com-BAL-41130ET 4:1 current balun. A bit pricy at $100.00, but worth every buck. I also added a 10 turn RF choke at the feed point. Absolutely no RF back to the shack on any of the 7 bands it is resonate on. Only running 100 watts, but antenna is low hanging at 35' with only about 50' of coax feeding from shack. 73 Gene N9TF K3S 10057 >I think we are drifting off topic, my apologies, but if you are considering an ocf dipole you can only prevent common mode currents by use of a double >wound balun, ie 2 separately made chokes connected together as a 4:1. A single core version does not properly cancel the common mode current that >results in unwanted radiation from your coax feeder and can make your equipment live to rf. > A huge amount of work has been done on this subject by DJ0IP and I suggest you look at his site > <http://www.dj0ip.de/balun-stuff/> http://www.dj0ip.de/balun-stuff/ is a good place to start. >The proof of the pudding is in the eating and I have not seen anyone do real world measurements like he has on real aerials. >David >G3UNA > > On 30 September 2015 at 20:51 Jerry Moore < <mailto:[hidden email]> [hidden email]> wrote: > > > What I don't understand is my previous radio didn't affect the TV > as far as I know (xyl never complained) so it has me perplexed because > the radio shouldn't matter. As far as the buckmaster ocf, it uses a > current transformer (auto-transformer )to balance the antenna and match the impedance. > Jer > > On September 28, 2015 1:37:16 PM EDT, Jim Brown > < <mailto:[hidden email]> [hidden email]> wrote: > >On Mon,9/28/2015 9:35 AM, dw wrote: > >> If a tuner is located at the rig-side of the coax, and the coax is at > >> high SWR, it could possibly be a cause for coax radiation. > > > >It doesn't work that way. > > > >Radiation from coax is the result of IMBALANCE in the antenna. A > >ferrite > >common mode choke at the feedpoint can fix that. > > > >73, Jim K9YC > >______________________________________________________________ > >Elecraft mailing list > >Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft > >Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm > >Post: <mailto:[hidden email]> mailto:[hidden email] > > > >This list hosted by: <http://www.qsl.net> http://www.qsl.net > >Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html > >Message delivered to <mailto:[hidden email]> [hidden email] > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. > ______________________________________________________________ > Elecraft mailing list > Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft > Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm > Post: <mailto:[hidden email]> mailto:[hidden email] > > This list hosted by: <http://www.qsl.net> http://www.qsl.net > Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html > Message delivered to <mailto:[hidden email]> [hidden email] > ______________________________________________________________ Elecraft mailing list Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm Post: <mailto:[hidden email]> mailto:[hidden email] This list hosted by: <http://www.qsl.net> http://www.qsl.net Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html Message delivered to <mailto:[hidden email]> [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Part of my confusion is based on this being a commercial solution that
didn't have a problem until recently. One thing I've thought of is that my TV configuration may have changed with the addition of a Chromecast..etc.. so I'll be doing a clean setup troubleshooting here soon (remove everything except power, see if I can duplicate.. if not then add antenna lead... if not ... add..etc.. ). The only other change in my environment is that the weather is raining and the antenna routes through a pear tree. So it's possible the wet foliage is contributing. If that's the case then the tree comes down. I'm expecting that it's something added/connected to the TV. Powerline filters haven't had any effect. I just realized my station safety grounds aren't connected because I'm still working on my Operating table hutch. Just have the trim and staining to finish for that. I'm also planning to run a dedicated power cable with heavier gauge wire to get a better ground at my station. Based on the TON of responses I've gotten I'll be running a heavy gauge THNN or similar from outside my station (where I'll add a ground rod) up to an antenna switch for grounding and bonding all of it together with the main ground on the other side of the house. I'm not sure how I'll NOT end up with a ground loop in this configuration. Main panel/ground is around 80' from the proposed shack ground rod. So the Main panel ground will come in via the heavy power cable. The shack side ground rod will bond to the heavy power cable ground. The antenna switch ground will run along the roof and down the side of the house to the shack ground rod. All internal shack equipment will be grounded via a heavy copper bus plate to the power cable ground. So the coax will end up being grounded in the shack AND via the antenna switch ground. From all of the reading the antenna switch ground is for lightning to have a lower impedance to ground OUTSIDE the house instead of through my gear/power system. It will be a bit to get this done as I'm having to replace antenna switches lost during a relocation. I have the antenna control boxes for the ameritron RCS8 and 4. Apparently I can't just buy the switch without the controlbox. Jer -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Gene Gabry Sent: Thursday, October 01, 2015 9:25 AM To: 'elecraft' Subject: Re: [Elecraft] K3S Proper Grounding Good information David. I also Have a 80m OCF http://www.slickpic.com/users/GeneGabry/albums/N9TFHamStationPhotos/?wallpap er <http://www.slickpic.com/users/GeneGabry/albums/N9TFHamStationPhotos/?wallpa per&viewer#8644290> &viewer#8644290 and choosing the correct balun and RF choke is paramount. I went with the (W2FMI design) Com-BAL-41130ET 4:1 current balun. A bit pricy at $100.00, but worth every buck. I also added a 10 turn RF choke at the feed point. Absolutely no RF back to the shack on any of the 7 bands it is resonate on. Only running 100 watts, but antenna is low hanging at 35' with only about 50' of coax feeding from shack. 73 Gene N9TF K3S 10057 >I think we are drifting off topic, my apologies, but if you are >considering an ocf dipole you can only prevent common mode currents by use of a double >wound balun, ie 2 separately made chokes connected together as a 4:1. >A single core version does not properly cancel the common mode current that >results in unwanted radiation from your coax feeder and can make your equipment live to rf. > A huge amount of work has been done on this subject by DJ0IP and I > suggest you look at his site > <http://www.dj0ip.de/balun-stuff/> http://www.dj0ip.de/balun-stuff/ is > a good place to start. >The proof of the pudding is in the eating and I have not seen anyone do real world measurements like he has on real aerials. >David >G3UNA > > On 30 September 2015 at 20:51 Jerry Moore < <mailto:[hidden email]> [hidden email]> wrote: > > > What I don't understand is my previous radio didn't affect the TV > as far as I know (xyl never complained) so it has me perplexed because > the radio shouldn't matter. As far as the buckmaster ocf, it uses a > current transformer (auto-transformer )to balance the antenna and > match the impedance. > Jer > > On September 28, 2015 1:37:16 PM EDT, Jim Brown > < <mailto:[hidden email]> [hidden email]> wrote: > >On Mon,9/28/2015 9:35 AM, dw wrote: > >> If a tuner is located at the rig-side of the coax, and the coax > is at > >> high SWR, it could possibly be a cause for coax radiation. > > > >It doesn't work that way. > > > >Radiation from coax is the result of IMBALANCE in the antenna. A > >ferrite > >common mode choke at the feedpoint can fix that. > > > >73, Jim K9YC > >______________________________________________________________ > >Elecraft mailing list > >Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft > >Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm > >Post: <mailto:[hidden email]> mailto:[hidden email] > > > >This list hosted by: <http://www.qsl.net> http://www.qsl.net > >Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html > >Message delivered to <mailto:[hidden email]> [hidden email] > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. > ______________________________________________________________ > Elecraft mailing list > Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft > Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm > Post: <mailto:[hidden email]> mailto:[hidden email] > > This list hosted by: <http://www.qsl.net> http://www.qsl.net > Please help support this email list: > <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html > Message delivered to <mailto:[hidden email]> [hidden email] > ______________________________________________________________ Elecraft mailing list Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm Post: <mailto:[hidden email]> mailto:[hidden email] This list hosted by: <http://www.qsl.net> http://www.qsl.net Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html Message delivered to <mailto:[hidden email]> [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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On Thu,10/1/2015 8:11 AM, [hidden email] wrote::
> Part of my confusion is based on this being a commercial solution that > didn't have a problem until recently. Buying "a commercial solution" seems to mean that you're assuming that whoever is selling a product really understands how antennas work and the shortcomings of the product they're selling, so you don't have to understand it. Part of being a ham is taking the time to actually learn how stuff works. I suggest that you study the links I posted yesterday. They are both tutorial and practical. > Just > have the trim and staining to finish for that. I'm also planning to run a > dedicated power cable with heavier gauge wire to get a better ground at my > station. Based on the TON of responses I've gotten I'll be running a heavy > gauge THNN or similar from outside my station (where I'll add a ground rod) > up to an antenna switch for grounding and bonding all of it together with > the main ground on the other side of the house. I'm not sure how I'll NOT > end up with a ground loop in this configuration. While a dedicated power line to your station is a good thing, there's too much foggy thinking and false logic in what some have been telling you to do. The earth is NOT a sump into which RFI is poured. Yes, you should run a bonding cable from your station to a ground rod, BUT that rod MUST be bonded to all other grounds for safety. What these two measures can do for you is CONTROL where common mode current flows -- it will flow on that new ground wire and that new dedicated power line -- but that RF current will still RADIATE, and can be picked up by any other wires in your home, like those in your home entertainment system. Caps added for emphasis. :) 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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This whole thread is quite amusing, no matter how much explanation takes
place, people still believe a ground rod is RF ground . Then the poor guy with the problem who states "nothing has changed" admits he has not grounded the station gear yet. but it was before. Talk about a lot of posting for nothing. I hope some of you will at least read and learn, there has been some great info put forth in this thread, and from the replies one can tell that some still dont get it. Thanks to Jim and others who have the patience to keep going over and over the facts trying to educate. Hope some of it sinks in, 73 Merv K9FD/KH6 WH2XCR 10/1/2015 8:11 AM, [hidden email] wrote:: >> Part of my confusion is based on this being a commercial solution that >> didn't have a problem until recently. > > Buying "a commercial solution" seems to mean that you're assuming that > whoever is selling a product really understands how antennas work and > the shortcomings of the product they're selling, so you don't have to > understand it. Part of being a ham is taking the time to actually > learn how stuff works. I suggest that you study the links I posted > yesterday. They are both tutorial and practical. > >> Just >> have the trim and staining to finish for that. I'm also planning to >> run a >> dedicated power cable with heavier gauge wire to get a better ground >> at my >> station. Based on the TON of responses I've gotten I'll be running a >> heavy >> gauge THNN or similar from outside my station (where I'll add a >> ground rod) >> up to an antenna switch for grounding and bonding all of it together >> with >> the main ground on the other side of the house. I'm not sure how I'll >> NOT >> end up with a ground loop in this configuration. > > While a dedicated power line to your station is a good thing, there's > too much foggy thinking and false logic in what some have been telling > you to do. The earth is NOT a sump into which RFI is poured. Yes, you > should run a bonding cable from your station to a ground rod, BUT that > rod MUST be bonded to all other grounds for safety. What these two > measures can do for you is CONTROL where common mode current flows -- > it will flow on that new ground wire and that new dedicated power line > -- but that RF current will still RADIATE, and can be picked up by any > other wires in your home, like those in your home entertainment system. > > Caps added for emphasis. :) > > 73, Jim K9YC > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Re: K3S Proper Grounding
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In reply to this post by Jim Brown-10
We're had a lot of posts on this topic. Ltt's let it rest for now in the
interest of relieving list email overload for others. thread closed. 73, Eric /Moderator etc. elecraft.com/ ==== On 10/1/2015 9:58 AM, Jim Brown wrote: > On Thu,10/1/2015 8:11 AM, [hidden email] wrote:: >> Part of my confusion is based on this being a commercial solution that >> didn't have a problem until recently. > > Buying "a commercial solution" seems to mean that you're assuming that whoever > is selling a product really understands how antennas work and the shortcomings > of the product they're selling, so you don't have to understand it. Part of > being a ham is taking the time to actually learn how stuff works. I suggest > that you study the links I posted yesterday. They are both tutorial and > practical. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Jim Brown-10
On Thu, Oct 1, 2015 at 12:58 PM, Jim Brown <[hidden email]>
wrote: > What these two measures can do for you is CONTROL where common mode > current flows -- it will flow on that new ground wire and that new > dedicated power line -- but that RF current will still RADIATE, and can be > picked up by any other wires in your home, like those in your home > entertainment system. It's even worse, as true what Jim says is. Short version: Common mode current messes up BOTH transmit and receive. Don't buy junk baluns and blockers. Insist on response curves from manufacturer. Never ever go cheep on baluns and blocking. Either buy or make the good stuff. Long version: The common mode path is a two way street. Many find attic antennas very noisy because they hear all the RF noise from all the stuff in the house. Changing to an outside antenna even a little ways from the house reduces that noise immensely. If a common mode path is open, it's an open road from the house to the antenna for house noise. At the antenna the house noise is added to the reception, making it much noisier. A common mode block working well enough to stop TX interference often still hasn't enough blocking to prevent the reverse path from raising your RX noise level. Designing your station to eliminate ground and common mode problems, before installing anything, will save you much consternation in the future. Understand there are companies who advertise in national magazines who sell junk baluns and junk common mode blocking devices. Or they say all-band when they barely cover down to 40 meters, if that. They are sure we are a bunch of dumb clucks who can't possibly tell the difference. Prove them wrong. Caveat Emptor. Buy from manufacturers that publish the response curves, with actual dB values, on all their devices. Ignore everyone else. 73, Guy K2AV ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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In reply to this post by Merv Schweigert
Ouch
Please discontinue this thread. I'll keep the rest of what I want to say to myself. -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Merv Schweigert Sent: Thursday, October 01, 2015 1:30 PM To: [hidden email] Subject: Re: [Elecraft] K3S Proper Grounding This whole thread is quite amusing, no matter how much explanation takes place, people still believe a ground rod is RF ground . Then the poor guy with the problem who states "nothing has changed" admits he has not grounded the station gear yet. but it was before. Talk about a lot of posting for nothing. I hope some of you will at least read and learn, there has been some great info put forth in this thread, and from the replies one can tell that some still dont get it. Thanks to Jim and others who have the patience to keep going over and over the facts trying to educate. Hope some of it sinks in, 73 Merv K9FD/KH6 WH2XCR 10/1/2015 8:11 AM, [hidden email] wrote:: >> Part of my confusion is based on this being a commercial solution >> that didn't have a problem until recently. > > Buying "a commercial solution" seems to mean that you're assuming that > whoever is selling a product really understands how antennas work and > the shortcomings of the product they're selling, so you don't have to > understand it. Part of being a ham is taking the time to actually > learn how stuff works. I suggest that you study the links I posted > yesterday. They are both tutorial and practical. > >> Just >> have the trim and staining to finish for that. I'm also planning to >> run a dedicated power cable with heavier gauge wire to get a better >> ground at my station. Based on the TON of responses I've gotten I'll >> be running a heavy gauge THNN or similar from outside my station >> (where I'll add a ground rod) up to an antenna switch for grounding >> and bonding all of it together with the main ground on the other side >> of the house. I'm not sure how I'll NOT end up with a ground loop in >> this configuration. > > While a dedicated power line to your station is a good thing, there's > too much foggy thinking and false logic in what some have been telling > you to do. The earth is NOT a sump into which RFI is poured. Yes, you > should run a bonding cable from your station to a ground rod, BUT that > rod MUST be bonded to all other grounds for safety. What these two > measures can do for you is CONTROL where common mode current flows -- > it will flow on that new ground wire and that new dedicated power line > -- but that RF current will still RADIATE, and can be picked up by any > other wires in your home, like those in your home entertainment system. > > Caps added for emphasis. :) > > 73, Jim K9YC > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > [hidden email] > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Re: K3S Proper Grounding
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This thread was closed over 2 hours ago.
73, Eric /elecraft.com/ On 10/1/2015 12:18 PM, [hidden email] wrote: > Ouch > > Please discontinue this thread. I'll keep the rest of what I want to say to > myself. > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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