If you want all the hairy details behind why the screen works and how it performs compared to conventional wire radials, I recommend you watch my original magic carpet video. ua-cam.com/video/UadUg5H8KO8/v-deo.html
_Yoink!_ Not only did I just order that fabric, I'm going to copy your bypass wire! I think I'll put grommets in the corners of the cloth, though, so I can stake it down. I'll just double up on the stakes and use them for a couple of guy strings. (I have Photographers' sandbags for when I can't drive stakes.) I've got the Wolf River "TIA" antenna for the big gun, and an inexpensive Chinese 40-6m vertical that's similar.
Well, that was 6 months ago, did you have a chance to test it yet? How did it go? Do the grommets work? Would you buy the cloth again? I’m about to make this.
Good stuff! I’ll be trying this, now people at the park will have to really put some effort to trip on my radials. They will anyway, but it’s going to be harder. 73!
Last summer on Independence Day, we were at the beach area of a small lake. We got there early enough to snag a picnic table under a shade tree. I had the vertical and window screen set up a good ten feet away from the paved path and people still managed to run into it.
In my original 'magic carpet' video we did WSPR testing between wire radials and window screen material and found no loss in performance between the two, and saw a slight boost in performance as we added more material. ua-cam.com/video/UadUg5H8KO8/v-deo.html In field testing over the last six months, I've observed signal reports to be the same with the screen material as with the wire radials.
New Tech here. Very well done on the SWR testing and field run. Working toward General, just got the FT891. Have been looking for portable gear setup - thanks for all the links! KK7SAB 73
It would be less durable for regular use, but if you needed to save even more weight and space for a backpacking trip I suspect you’d get similar results from an aluminized mylar emergency blanket.
Michael, thank you for the information on the Faraday cloth, I was just going to get some screening material until I seen your video regarding the Faraday cloth, and for compactness this seems to the "ticket". Thank you for sharing and until next video, have a great day.
I have a Faraday cloth waiting for me at the house. I will break it in for a Radio merit badge class and JOTA/JOTI on Saturday. Thanks Michael! 73 KR5EBS
Huge fan of the window mesh and really like this idea too. Do you have a lead going clipped to the cloth as well or is your stand just sitting on it. I can't really tell.
@@KB9VBRAntennasThank for this update. Fascinating! I’ve used the screenwire as you have but it was really windy recently so I fastened down the corners using aluminum tent pegs (lightweight) and hooked up both the pegs and screen. Works wonderfully well. Probably overkill. Also, the Amazon link in your video for the faraday cloth says to not wash it except sparingly and gently and to not dry it in the sun. So, is this a problem to consider? N4LWT. 73
It will be interesting to try this where I live in South West Western Australia....you run a magnet across the ground and half of the ground follows you around. Looks nice and light for SOTA work...cant wait to try it. 73 de VK6MMB
I am using the 17 foot Wolf River telescoping antenna, along with 18 16.5 foot radial wires. I have found that adding the additional radials dropped my SWR quite a bit, easily within operating range for any band between 6-40 meters. I purchased an aluminum window screen last weekend, just haven't tried it out yet. I will get a Faraday screen like the one in your video, and also pick up the same antenna mount that you are using in this video. Thanks!
I've also had very good luck with lots of little radials. That's what led me to testing and using the screen, as I surmised that surface area coverage is more important than radial length.
Purely resistive feedpoint impedance does not mean all the power is radiated. Full 1/4 wavelength vertical monopole antenna has a radiation resistance of about 36 ohm, so if your total resistive component is 50 ohm, the ground loss of 14 ohm is in the series circuit to make the total of 50. That 14 ohm is a pure loss and not radiated. With a loading coil, the antenna's radiation resistance drops rapidly, very often around 5 ohm range, so a good SWR is actually an indicator of warming the ground rather than good radiation. Also, the measurement is influenced by the presence of the coax. The best way to measure is to use a very short coax pigtail for measurement. The next best is to use a very low loss coax carefully adjusted cut at exactly 1/2 wavelength (electrical length, factoring the actual velocity factor, not the nominal catalog spec number). Obviously, the former is easier in multi-band antennas.
This is why every day I look for your inside and knowledge. I have one question. I did not see you ground the faraday cloth to the base of the antenna. I am assuming that just by setting the tripod on the faraday cloth gives sufficient contact to complete the antenna system. I did notice that the faraday cloth did roll over in the breeze. You mentioned that you would be putting s few grommets in the corners to keep it flat and deployed. I was thinking a few very large washers glued to the cloth in the corners. Thank you for sharing this with us, and thank you for your UA-cam channel.
Hey thanks for this - a new one for me as I am always looking to improve antenna performance with just 10 watts allowed by my licence. The bonus is that might wife says if I buy a big bit she will line my hat for me with the excess 🙂. 73 M7BLC.
Just so I understand, I'm using a PAC 12 antenna. Will this cloth replace the radials that come with it, or is it used with the radials. Thanks. Love your channel. 73, KM4PMP
Recently replaced my metal roof, and using ALL of the original roof (from the early 1900's) on the ground: (1) it kills the bamboo I have been trying to get under control that someone else planted years ago (2) makes the most rad ground plane ever (3) doubt someone will be able to sneak up to my windows at night - the sound of walking on metal is LOUD! With my Wolf River + ground radials, it makes a totally rad ground plane!
Definitely more compact and packable. The window screen has the advantage that you can probably find it at any local hardware store. Oh, no. I just realized it is a compromised ground plane. 😉 U-rah-rah
How much power can you put into the faraday cloth? Will it handle 100 watts? 1000 watts? Thinking of VK3YE and his pedestrian HF mobile - faraday toga? ⚡ Trailing cape like a superhero? 😁 Cool idea!
100 watts no problem. I don't know about 1000. I usually run 50 watts in the field. I wouldn't have any concerns with wearing it as a toga and running QRP portable.
I wonder how a Space Blanket, the full size one with grommets, would work? That's silvered or metallic mylar fabric on one side, IIRC. Not the same as the disposable ones--which might be worth looking at.
I have a Ham friend in town that did the faraday cloth with a metal foot tripod, with a 5 foot 20m ham stick. He was running a Zeigu 20 watt radio. He got good swr, and from NE Oklahoma he talked to Corpus Christi, Texas, New Jersey and Ohio while I was there. So I got my 10 foot tripod out and connected a 20m ham stick on top of it. I then a added a 12 gauge wire with small battery clamp connectors on either end of the wires. The 12 gauge wire was a little over 10 feet long, one end connected the antenna coax bracket on top of the tripod, the other end connected to the faraday cloth. Using a Yaesu FT-891 and a MFJ manual tuner, with 95 watts; I got really good swr and talked to few East Coast stations and tried to fight through a pile up from a Hawaii station coming in 5x7. I’m sold on the faraday magic carpet.
You inspired me to try- purchased off of Amazon, and it’s quite the game changer. I appreciate your videos, content, and dedication. It’s difficult to find prime material today, aside from the few of you who do ham right!!! Thank you again, and 73 DE Andrew K7RXT
As long as your base or stand allows for electrical conductivity from the cloth to the ground side of the antenna, you don't require any jumpers or connections from the cloth to the antenna. The base provides the connection. If the base is plastic or insulated from the ground side, then a jumper is required.
In Wisconsin we suffer from very poor ground conductivity due to the high amount of granite bedrocks. I've found the window screen method to be a bit more forgiving. In some locations I'd be constantly tweaking radials, but with the screen, the match came easier. Not perfect, but easier.
Impedance of a 1/4 wavelength monopole should be around 37 ohms, not 50 ohms, indicating that your screening is ineffective. Your concept of "50 ohms is good" is all wrong. Further....Being "broadband" indicates resistive losses, another negative. Lastly... Resonance is established when reactance equals zero. 50 ohms has nothing to do with resonance.
This is essentially a ground plane. What are your test numbers (SWR, etc.) without the screen compared to the screen? Need before and after with and without screen. Using a field strength meter. And actual signals from other Hams.
My original video on the windows screen ground plane, which is referenced in the video description, goes through all the stats, numbers, and performance metrics that you are looking for. Performance was the same between the screen and the cloth, so I didn't recreate all that data a second time: ua-cam.com/video/UadUg5H8KO8/v-deo.html
Thanks for all the good work you do Michael. You’re one of my favourite channels. I can’t believe I haven’t already subscribed! I fixed that quick and look forward to more of your excellent videos….
I tried using duct tape for the fraying on the window screen but it wouldn't stick well and comes off, whereas on the Faraday fabric it works great to stop the fraying.
From other replies here I understand as long as you get continuity they should work. After Ive read through the rest of the comments here Im off into the garage to test the foil blankets I have in my first aid kit
Experiment with a circle of cloth or a square. Help reduce any directional effect. Try using it length way different directions. See if you get any directional benefits
The shape of the cloth really doesn't make a different. It's surface area coverage that you need to be concerned about. According to Robert Sherwood's May 1977 article in Ham Radio Magazine, you need at least a 1/4 wave of material in order to affect directivity: ia903006.us.archive.org/12/items/hamradiomag/ham_radio_magazine/Ham%20Radio%20Magazine%201977/05%20May%201977.pdf
I really like the concept but do you think that either the screen or the faraday cafe work just as well if it's either cut to a perfect square or folded over into a perfect square? I ask this because I believe if it works the square would take up much less space on the ground and maybe make a more compact fold. Thanks again for these wonderful videos. 73 KN4MXZ
I don't believe the shape of the cloth or screen makes a difference. It's the surface area coverage that matters. A smaller screen will work fine on the upper bands, but for 40 meters and lower, you will need more surface area.
@@davewhite7679The Amazon site listed in this video mentions not to wash it except by hand and to dry it in the shade. So it is a bit unclear if it can be used well on the ground. Apparently it will work well dry but maybe not wet. We shall see.
I think the cautions may have to do with the cloth's ability to 'block' RF signals. Since we aren't really using it for its intended purpose, I don't know what the long effects will be with exposure to sun and water. I guess we'll find out.
It depends on your base or tripod. If you have good continuity to the ground side of the antenna through the base, then you can set it directly on top of the cloth.
Be careful on the length of the lead from mesh/cloth to tripod. I took the mesh portable with my WRC and SWR was 7:1 until I realized my lead had uncoiled. Coiled it back up and it was fine.
I'm trying to get the Sporty Forty coil to work with my 213" whip. Did this work on 40m? I didn't see any QSOs with 40m. I have tried 5x 35' radials. WRC FAQ mentioned that 3 would work, but more are better. I had enough wire for five radials. That did not work. I was going to the hardware store for screen material, but this product looks easier to carry for POTA.
These smaller pieces of material really don't offer any directivity. You would need a quarter wave or more of material for that to happen. In using the window screen for the last six months, I've found the contact patterns to be quite similar and typical for my geographic location.
Fabric weights will work. Round Magnetic Drapery Weights Shower Curtain Weights Strong Tablecloth Magnets Bottom No Sew Curtain Weights Waterproof Magnetic Curtain Weights for Drapery Curtain Tablecloth (Black, 12 Pairs)
Are there any comparable numbers with four radial wires? It works but how much better? Looks easier than spreading wires and is more visible to anyone close by.
In my original 'magic carpet' video we did WSPR testing between wire radials and window screen material and found no loss in performance between the two, and saw a slight boost in performance as we added more material. ua-cam.com/video/UadUg5H8KO8/v-deo.html In field testing over the last six months, I've observed signal reports to be the same with the screen material as with the wire radials.
I want it ! I'm all about man portable QRP. A light weight package with fast set up and tear down times. Been looking for a cloth like screen that doesn't cost a fortune. Going to check the prices on this. Also love RG8X. It's a little heavier and stiffer than RG58 but for 5 W operations every dB counts for telephony.
We were doing this 40 years ago Using hog panels. On my ranch I had a vertical, I used 8 hog panels tied together on the ground underneath it to form a ground plane, it worked really well. What I don't understand is with all those trees why in the world are you using a lossy vertical, i'd understand it for 40 and 80 meters but for anything under 40 you'd be much better off with a wire in the trees. I have a little drone that I keep with me specifically for launching wire antennas into trees good it has a payload release mechanism on the bottom of it that drops a weighted line over the top of the tree and allows me to hoist up antennas.
This concept has been around for a long time. In my research for the video I found a magazine article from 1977 that confirms the same things we found with the ground screen (link in the video description). AM broadcasters have been doing similar things for even longer. As for using a vertical antenna for the low bands, I use a wide variety of styles of antennas and will often pick the best tool for the job. Sometimes trees aren’t available to hang wire or the park has restrictions. Space may also be an issue. In many cases a 1/4 wave vertical with a good ground network will perform as good or better than an end fed half wave on the upper bands, and can be easier and quicker to deploy than a dipole.
What headset are you using and what brand of magic carpet do you suggest for 10-80 I have regular wolferiver coil , got replacement coil but found my lost coil
It shouldn't have an effect if you are getting a good connection from the antenna to the fabric. But that's not really an intended purpose of the faraday cloth and extended contact with moisture will cause it to rapidly degrade. If you are wanting to bury a ground network, I would consider something more substantial like hardware cloth.
You didn't show us a comparison between the Faraday and the window screen nor did you show us what your readings were with no groundplane. Showing the contacts you made doesn't really show the effectiveness of the groundplane.
The faraday cloth is functionally equivalent to an aluminum window screen ground network. I will refer you to my original window screen ground video that answers your questions: ua-cam.com/video/UadUg5H8KO8/v-deo.html
Portable # (in this case Portable 4) is a bit of an antiquated term, but what the other person is saying is that they are operating outside of their normal callsign district. For example, if a person's callsign is K9XYZ and their are in the #4 call district (or any other district for that matter), announcing that they are portable tells you they are outside of where they normally operate. The FCC required this at one time, but the practice was largely given up when you where no longer required to have a callsign from the district in which you reside. For example, if you moved to another state in another callsign district, the FCC required you to change your call to that district. This is no longer the case. The Portable operation designator somehow still sticks, but it is not required.
Very interesting. Brings up a few questions in my mind plus some experiments I may do for fun. Could you see any change in SWR as the wind blew the cloth? I wonder how the SWR (impedance) changes as you roll up (make the area smaller) the fabric. I also wonder what the change is as you increase the spacing to the “dirt”. (How far the grass and leaves holds the fabric (I look at it as a capacitor plate) above the soil. I have been meaning to take some readings on my radials to gather some data. I may need to include some fabric in the mix. 73, de N4DJ
When using that Faraday cloth or window screen, is it better to have the antenna lower to the ground instead of being on a tripod and 6 feet in the air?
Here you go: Heil Ham Radio BM-17 Dual headset: heilhamradio.com/product/bm-17-2/ How I record my contact audio: ua-cam.com/video/tOqzZPphE7k/v-deo.html My headset trigger switch: ua-cam.com/video/b5Wu8BlrSF0/v-deo.html
I'm still using the Heil BM-17 headset. Here's some resources on my headphone setup and how I record transceiver audio: How I record my contact audio: ua-cam.com/video/tOqzZPphE7k/v-deo.html My headset trigger switch: ua-cam.com/video/b5Wu8BlrSF0/v-deo.html Heil Ham Radio BM-17 Dual headset: heilhamradio.com/product/bm-17-2/
Michael are you connecting the base of the coil mount to the fabric via hard wire, or is the ground connection made simply with the tripod legs making contact ? Thanks !
My antenna base is solid metal and setting it on top of the screen resulted in good contact and continuity. If you are using a non-metal tripod, I'd make a connection with a couple-three jumper wires.
Sounds good probably end up getting that eventually I'm just getting back into ham so I'm trying different stuff but I like the idea of the cloth thank you
Thanks again for another great video. The worst part of pota is untangling ground plane wires. I use a copper stake for my sporty fourty and whip so I'll put a large homemade grommet dead center made of 2 pieces of aluminum riveted through the cloth and attach a power pole wire to one of the rivets. I like the idea of tent spikes on the corner. KD2RLB, 73
I have been using this in multiple configurations including very similar to yours. I am a big believer and have had pretty great results. Most importantly, it takes up no space! Thanks for the video! 73 KF0LTY.
Oddly enough, I tried this and was unable to get a remotely decent SWR. The lowest I could get on any band was about a 1.9:1, and that took some doing. With 12 16' radials it works like a charm, but with the Faraday cloth, not so much. I may have to mess with it some more and see what I can do, but as of now it won't get the job done.
I've noticed that ground conductivity can have an effect on the window screen or cloth. It may just be the location. Try a different spot and see if you get the same results.
Shape doesn't matter, it can be square or round. It's the square foot coverage that you should be concerned about. More is generally better, until you get to 120 square feet. Then the marginal gains greatly diminish. Robert Sherwood demonstrated that in his May 1977 article in Ham Radio magazine. Link to it is in the description found in my original window screen video: ua-cam.com/video/UadUg5H8KO8/v-deo.html
The cloth won't fully attenuate RF signals, but it does lower them. The way RFI gets into computers is often through the cables, so common mode chokes would probably be more effective.
Thank you. I have ferrite beads on all cables and power cords. I might go the route for my computer’s monitor. On some bands it is affected by the transmission from the radio when using an random wire antenna. The transmission is much closer than a dipole on coax.
Yes it will. The antenna is just a 213 inch collapsible whip. you can adjust the whip length to a 1/4 wave for any frequency between 14.000 Mhz and 54 Mhz.
If you want all the hairy details behind why the screen works and how it performs compared to conventional wire radials, I recommend you watch my original magic carpet video. ua-cam.com/video/UadUg5H8KO8/v-deo.html
I predict hats of this cloth, way more comfortable than tin foil. Thank you though, this is a better way to antenna.
They are already made. Search the Internet.
Would that come in cowboy style.
Just asken
Lol hats of this material that’s primo!
😂@@DCDura
Looks like it works as good as the window screen. Thanks for sharing.
This is something I will try. I hate screen material but faraday is a lot more forgiving in use. Good job!
It certainly folds up into a smaller package, which is really nice.
_Yoink!_ Not only did I just order that fabric, I'm going to copy your bypass wire! I think I'll put grommets in the corners of the cloth, though, so I can stake it down. I'll just double up on the stakes and use them for a couple of guy strings. (I have Photographers' sandbags for when I can't drive stakes.) I've got the Wolf River "TIA" antenna for the big gun, and an inexpensive Chinese 40-6m vertical that's similar.
Grommets area good idea. I guess I need a grommet tool now.
Well, that was 6 months ago, did you have a chance to test it yet? How did it go? Do the grommets work? Would you buy the cloth again? I’m about to make this.
I want to try 3 30' tape measures connected with allegator clips. Easy to put out and store.
Good stuff! I’ll be trying this, now people at the park will have to really put some effort to trip on my radials. They will anyway, but it’s going to be harder. 73!
Last summer on Independence Day, we were at the beach area of a small lake. We got there early enough to snag a picnic table under a shade tree. I had the vertical and window screen set up a good ten feet away from the paved path and people still managed to run into it.
Thanks! I just ordered one
I thinks we would need to see the data without the faraday cloth for comparison. Not sure. You are the man. Great work.
In my original 'magic carpet' video we did WSPR testing between wire radials and window screen material and found no loss in performance between the two, and saw a slight boost in performance as we added more material. ua-cam.com/video/UadUg5H8KO8/v-deo.html In field testing over the last six months, I've observed signal reports to be the same with the screen material as with the wire radials.
New Tech here. Very well done on the SWR testing and field run. Working toward General, just got the FT891. Have been looking for portable gear setup - thanks for all the links! KK7SAB 73
It would be less durable for regular use, but if you needed to save even more weight and space for a backpacking trip I suspect you’d get similar results from an aluminized mylar emergency blanket.
Activated 4 parks, 3 new to me, with the faraday cloth. So easy! I threw it over the bed of the pickup on for 3 new parks.....worked great!
Michael, thank you for the information on the Faraday cloth, I was just going to get some screening material until I seen your video regarding the Faraday cloth, and for compactness this seems to the "ticket". Thank you for sharing and until next video, have a great day.
Faraday cloth.. Brilliant! 73!
Excelent Info. Thanks NP4VO Jose 73s
...And it will keep you warm and cozy on those cold
Wisconsin nights. Thanks for the video from K1NEO, Maine.
It's a bit sparkly too, so I feel very fashionable.
I have a Faraday cloth waiting for me at the house. I will break it in for a Radio merit badge class and JOTA/JOTI on Saturday. Thanks Michael! 73 KR5EBS
Huge fan of the window mesh and really like this idea too. Do you have a lead going clipped to the cloth as well or is your stand just sitting on it. I can't really tell.
I laid the antenna base directly onto the cloth. It made a direct connection so I didn't need to add any jumper wires
@@KB9VBRAntennasThank for this update. Fascinating! I’ve used the screenwire as you have but it was really windy recently so I fastened down the corners using aluminum tent pegs (lightweight) and hooked up both the pegs and screen. Works wonderfully well. Probably overkill.
Also, the Amazon link in your video for the faraday cloth says to not wash it except sparingly and gently and to not dry it in the sun. So, is this a problem to consider? N4LWT. 73
It will be interesting to try this where I live in South West Western Australia....you run a magnet across the ground and half of the ground follows you around. Looks nice and light for SOTA work...cant wait to try it. 73 de VK6MMB
I was just at the same park a week ago or so. Did a quick activation and then found a few pounds of oyster mushrooms. 😉 cool place for sure.
It's a nice park and I only live 20 minutes away. You should have given me a shout.
Next up- chain link fence. Not terribly portable but when one is present...
I am using the 17 foot Wolf River telescoping antenna, along with 18 16.5 foot radial wires. I have found that adding the additional radials dropped my SWR quite a bit, easily within operating range for any band between 6-40 meters. I purchased an aluminum window screen last weekend, just haven't tried it out yet. I will get a Faraday screen like the one in your video, and also pick up the same antenna mount that you are using in this video. Thanks!
I've also had very good luck with lots of little radials. That's what led me to testing and using the screen, as I surmised that surface area coverage is more important than radial length.
Purely resistive feedpoint impedance does not mean all the power is radiated. Full 1/4 wavelength vertical monopole antenna has a radiation resistance of about 36 ohm, so if your total resistive component is 50 ohm, the ground loss of 14 ohm is in the series circuit to make the total of 50. That 14 ohm is a pure loss and not radiated. With a loading coil, the antenna's radiation resistance drops rapidly, very often around 5 ohm range, so a good SWR is actually an indicator of warming the ground rather than good radiation. Also, the measurement is influenced by the presence of the coax. The best way to measure is to use a very short coax pigtail for measurement. The next best is to use a very low loss coax carefully adjusted cut at exactly 1/2 wavelength (electrical length, factoring the actual velocity factor, not the nominal catalog spec number). Obviously, the former is easier in multi-band antennas.
Still the best online Elmer any ham can have! Great video Michael!
This is why every day I look for your inside and knowledge. I have one question. I did not see you ground the faraday cloth to the base of the antenna. I am assuming that just by setting the tripod on the faraday cloth gives sufficient contact to complete the antenna system. I did notice that the faraday cloth did roll over in the breeze. You mentioned that you would be putting s few grommets in the corners to keep it flat and deployed. I was thinking a few very large washers glued to the cloth in the corners. Thank you for sharing this with us, and thank you for your UA-cam channel.
I laid the antenna base directly onto the cloth. It made a direct connection so I didn't need to add any jumper wires
There have been some people adding grommets to the Faraday cloth to assure a ground plane.
Hey thanks for this - a new one for me as I am always looking to improve antenna performance with just 10 watts allowed by my licence. The bonus is that might wife says if I buy a big bit she will line my hat for me with the excess 🙂. 73 M7BLC.
Just so I understand, I'm using a PAC 12 antenna. Will this cloth replace the radials that come with it, or is it used with the radials. Thanks. Love your channel. 73, KM4PMP
Love it.... Thanks for a no BS straight up analysis of this cloth.... I'm going to buy some now. Great video
Recently replaced my metal roof, and using ALL of the original roof (from the early 1900's) on the ground: (1) it kills the bamboo I have been trying to get under control that someone else planted years ago (2) makes the most rad ground plane ever (3) doubt someone will be able to sneak up to my windows at night - the sound of walking on metal is LOUD! With my Wolf River + ground radials, it makes a totally rad ground plane!
Definitely more compact and packable. The window screen has the advantage that you can probably find it at any local hardware store. Oh, no. I just realized it is a compromised ground plane. 😉 U-rah-rah
How much power can you put into the faraday cloth? Will it handle 100 watts? 1000 watts?
Thinking of VK3YE and his pedestrian HF mobile - faraday toga? ⚡ Trailing cape like a superhero? 😁
Cool idea!
100 watts no problem. I don't know about 1000. I usually run 50 watts in the field. I wouldn't have any concerns with wearing it as a toga and running QRP portable.
I think I need to get some of this. Looks much easier than try to keep a lot of ground radials from tangling and deploying them.
Yes, I posted my results on another comment that the faraday cloth works!
I wonder how a Space Blanket, the full size one with grommets, would work? That's silvered or metallic mylar fabric on one side, IIRC. Not the same as the disposable ones--which might be worth looking at.
If the blanket offers continuity or an electrical connection to the ground side of the antenna, it should work.
Good demo!
Might want to check KE9TT/4 QTH if you haven't done so already. Definitely not Virginia Beach!
I’ve been using the Faraday cloth for about a month now, works great , going to put some grommets into it for some spikes so it won’t fly away. KB2GCG
I found that using fishing weights were a much easier alternative and didn’t seem to have any negative affect
I have a Ham friend in town that did the faraday cloth with a metal foot tripod, with a 5 foot 20m ham stick. He was running a Zeigu 20 watt radio. He got good swr, and from NE Oklahoma he talked to Corpus Christi, Texas, New Jersey and Ohio while I was there. So I got my 10 foot tripod out and connected a 20m ham stick on top of it. I then a added a 12 gauge wire with small battery clamp connectors on either end of the wires. The 12 gauge wire was a little over 10 feet long, one end connected the antenna coax bracket on top of the tripod, the other end connected to the faraday cloth. Using a Yaesu FT-891 and a MFJ manual tuner, with 95 watts; I got really good swr and talked to few East Coast stations and tried to fight through a pile up from a Hawaii station coming in 5x7. I’m sold on the faraday magic carpet.
Can we place the magic carpet between the roof of a vehicle and a tri mag mount? Would it improve signal strength or is it overkill on a steel roof?
Great question hoping you get a reply
Grommets and tent stakes sounds like the way to go. Good idea.
You inspired me to try- purchased off of Amazon, and it’s quite the game changer. I appreciate your videos, content, and dedication. It’s difficult to find prime material today, aside from the few of you who do ham right!!! Thank you again, and 73
DE
Andrew K7RXT
So you just set up by placing WRC ON CLOTH and attach coax. Is anything attached to cloth?? Thank you , I love your channel! ❤️😀
As long as your base or stand allows for electrical conductivity from the cloth to the ground side of the antenna, you don't require any jumpers or connections from the cloth to the antenna. The base provides the connection. If the base is plastic or insulated from the ground side, then a jumper is required.
It would be interesting to see how it works in the Seattle area (K-3216, K-3261, etc) where I have to adjust the radials for every band change
In Wisconsin we suffer from very poor ground conductivity due to the high amount of granite bedrocks. I've found the window screen method to be a bit more forgiving. In some locations I'd be constantly tweaking radials, but with the screen, the match came easier. Not perfect, but easier.
What do you think that I would do better without a faraday cloth in North Carolina near the coast?
Impedance of a 1/4 wavelength monopole should be around 37 ohms, not 50 ohms, indicating that your screening is ineffective. Your concept of "50 ohms is good" is all wrong. Further....Being "broadband" indicates resistive losses, another negative. Lastly... Resonance is established when reactance equals zero. 50 ohms has nothing to do with resonance.
This is essentially a ground plane. What are your test numbers (SWR, etc.) without the screen compared to the screen? Need before and after with and without screen. Using a field strength meter. And actual signals from other Hams.
My original video on the windows screen ground plane, which is referenced in the video description, goes through all the stats, numbers, and performance metrics that you are looking for. Performance was the same between the screen and the cloth, so I didn't recreate all that data a second time: ua-cam.com/video/UadUg5H8KO8/v-deo.html
OK thanks. Ill check it out. 73
Thanks for all the good work you do Michael. You’re one of my favourite channels. I can’t believe I haven’t already subscribed! I fixed that quick and look forward to more of your excellent videos….
I tried using duct tape for the fraying on the window screen but it wouldn't stick well and comes off, whereas on the Faraday fabric it works great to stop the fraying.
I would assume that the faraday magic carpet cloth flys better than the window screen 😂
How about using a foil emergency blanket these are bigger and a lot cheaper I have tried one and seems ok but maybe not as good as Faraday cloth
From other replies here I understand as long as you get continuity they should work. After Ive read through the rest of the comments here Im off into the garage to test the foil blankets I have in my first aid kit
Experiment with a circle of cloth or a square. Help reduce any directional effect. Try using it length way different directions. See if you get any directional benefits
The shape of the cloth really doesn't make a different. It's surface area coverage that you need to be concerned about. According to Robert Sherwood's May 1977 article in Ham Radio Magazine, you need at least a 1/4 wave of material in order to affect directivity: ia903006.us.archive.org/12/items/hamradiomag/ham_radio_magazine/Ham%20Radio%20Magazine%201977/05%20May%201977.pdf
Bought some off of Amazon, didn't make any appreciable difference that I could tell.
Expert activation! You don't often get to hear a pileup in the videos.
I was thinking the same thing.
How useful would this be at VHF / UHF frequencies? 73 DE N9THH
I really like the concept but do you think that either the screen or the faraday cafe work just as well if it's either cut to a perfect square or folded over into a perfect square? I ask this because I believe if it works the square would take up much less space on the ground and maybe make a more compact fold. Thanks again for these wonderful videos. 73 KN4MXZ
I don't believe the shape of the cloth or screen makes a difference. It's the surface area coverage that matters. A smaller screen will work fine on the upper bands, but for 40 meters and lower, you will need more surface area.
“Magic carpet”?? It doesn’t fly!
You could stitch it inside a waterproof fabric canvas
My Faraday cloth actually claims to be washable. 😃
KZ9V
@@davewhite7679The Amazon site listed in this video mentions not to wash it except by hand and to dry it in the shade. So it is a bit unclear if it can be used well on the ground. Apparently it will work well dry but maybe not wet. We shall see.
I think the cautions may have to do with the cloth's ability to 'block' RF signals. Since we aren't really using it for its intended purpose, I don't know what the long effects will be with exposure to sun and water. I guess we'll find out.
As always great Video. I don’t see a connection from the stand to the cloth. Is it not needed?
It depends on your base or tripod. If you have good continuity to the ground side of the antenna through the base, then you can set it directly on top of the cloth.
A 2m quarter wave mag mount on the roof of a car is insulated from the metal roof, so maybe an electrical connection isn't essential.
If using a non metallic tripod, would you run a wire from the antenna somewhere to the ground network?
I'd run at wires, from the ground side of the tripod to the screen or cloth. It seems the more connections you make, the better the match.
Be careful on the length of the lead from mesh/cloth to tripod. I took the mesh portable with my WRC and SWR was 7:1 until I realized my lead had uncoiled. Coiled it back up and it was fine.
I'm trying to get the Sporty Forty coil to work with my 213" whip. Did this work on 40m? I didn't see any QSOs with 40m. I have tried 5x 35' radials. WRC FAQ mentioned that 3 would work, but more are better. I had enough wire for five radials. That did not work. I was going to the hardware store for screen material, but this product looks easier to carry for POTA.
Perhaps lay a second one perpendicular on top and create a X. It may give a better omni directional pattern.
These smaller pieces of material really don't offer any directivity. You would need a quarter wave or more of material for that to happen. In using the window screen for the last six months, I've found the contact patterns to be quite similar and typical for my geographic location.
Michael just took us on a magic carpet ride!
Nice, I gotta give this a try!
Fabric weights will work.
Round Magnetic Drapery Weights Shower Curtain Weights Strong Tablecloth Magnets Bottom No Sew Curtain Weights Waterproof Magnetic Curtain Weights for Drapery Curtain Tablecloth (Black, 12 Pairs)
Enjoying your videos! My last piece of equipment for POTA is a laptop, what program are you using for logging your contacts? Thanks
Dave
W4FSW
I'm using Hamrs (www.hamrs.app) on an inexpensive Windows PC
Didn't you recognize Rob N1NUG from the SevenFortyOne YT channel?
Great find. Use a Faraday bag for my car keys and credit cards. Works great. But now, this is a great idea. Thanks for the tip.
Are there any comparable numbers with four radial wires? It works but how much better? Looks easier than spreading wires and is more visible to anyone close by.
In my original 'magic carpet' video we did WSPR testing between wire radials and window screen material and found no loss in performance between the two, and saw a slight boost in performance as we added more material. ua-cam.com/video/UadUg5H8KO8/v-deo.html In field testing over the last six months, I've observed signal reports to be the same with the screen material as with the wire radials.
Would this work with a ATAS-120 mounted on a tri-magnet placed on the magic carpet on the ground? Anyone?
That's a great question. I don't have an ATAS-120, so I am unable to test it. If you have one, try it and report back.
Hopefully, neighbors will not call the cops on you, Michael 😂 Most everything us hams do could look strange to them, if you know what I mean😂😂
I haven't had a problem yet. Although I am pretty sure all my neighbors think I'm crazy.
I want it ! I'm all about man portable QRP. A light weight package with fast set up and tear down times. Been looking for a cloth like screen that doesn't cost a fortune. Going to check the prices on this. Also love RG8X. It's a little heavier and stiffer than RG58 but for 5 W operations every dB counts for telephony.
We were doing this 40 years ago Using hog panels. On my ranch I had a vertical, I used 8 hog panels tied together on the ground underneath it to form a ground plane, it worked really well.
What I don't understand is with all those trees why in the world are you using a lossy vertical, i'd understand it for 40 and 80 meters but for anything under 40 you'd be much better off with a wire in the trees.
I have a little drone that I keep with me specifically for launching wire antennas into trees good it has a payload release mechanism on the bottom of it that drops a weighted line over the top of the tree and allows me to hoist up antennas.
This concept has been around for a long time. In my research for the video I found a magazine article from 1977 that confirms the same things we found with the ground screen (link in the video description). AM broadcasters have been doing similar things for even longer.
As for using a vertical antenna for the low bands, I use a wide variety of styles of antennas and will often pick the best tool for the job. Sometimes trees aren’t available to hang wire or the park has restrictions. Space may also be an issue. In many cases a 1/4 wave vertical with a good ground network will perform as good or better than an end fed half wave on the upper bands, and can be easier and quicker to deploy than a dipole.
walt made it in
What headset are you using and what brand of magic carpet do you suggest for 10-80 I have regular wolferiver coil , got replacement coil but found my lost coil
What head set are you using ? I'm looking for something hands free with a PTT capability.
It's the Heil BM-17 dual side headset
Do you have to make sure you get "reflective" vs "absorbant" fabric - I'm looking at using it for a folding parabolic EME dish.
Hi Dan, I think that you have a good point; see my comment regarding RF loss-angle 😛
What effect would a layer of gravel on top of the faraday cloth have on tx/rx?
It shouldn't have an effect if you are getting a good connection from the antenna to the fabric. But that's not really an intended purpose of the faraday cloth and extended contact with moisture will cause it to rapidly degrade. If you are wanting to bury a ground network, I would consider something more substantial like hardware cloth.
You didn't show us a comparison between the Faraday and the window screen nor did you show us what your readings were with no groundplane. Showing the contacts you made doesn't really show the effectiveness of the groundplane.
The faraday cloth is functionally equivalent to an aluminum window screen ground network. I will refer you to my original window screen ground video that answers your questions: ua-cam.com/video/UadUg5H8KO8/v-deo.html
What size was the mat you were using in the video
Three yards, 44x108 inches. There's a link to it in the video description.
What does portable 4 mean out there please? Heard someone call in with callsign then portable 4?? Thanks
Portable # (in this case Portable 4) is a bit of an antiquated term, but what the other person is saying is that they are operating outside of their normal callsign district. For example, if a person's callsign is K9XYZ and their are in the #4 call district (or any other district for that matter), announcing that they are portable tells you they are outside of where they normally operate.
The FCC required this at one time, but the practice was largely given up when you where no longer required to have a callsign from the district in which you reside. For example, if you moved to another state in another callsign district, the FCC required you to change your call to that district. This is no longer the case. The Portable operation designator somehow still sticks, but it is not required.
Very interesting. Brings up a few questions in my mind plus some experiments I may do for fun.
Could you see any change in SWR as the wind blew the cloth? I wonder how the SWR (impedance) changes as you roll up (make the area smaller) the fabric. I also wonder what the change is as you increase the spacing to the “dirt”. (How far the grass and leaves holds the fabric (I look at it as a capacitor plate) above the soil. I have been meaning to take some readings on my radials to gather some data. I may need to include some fabric in the mix.
73, de N4DJ
When using that Faraday cloth or window screen, is it better to have the antenna lower to the ground instead of being on a tripod and 6 feet in the air?
Lower is better. The screen or cloth seems to lose its effectiveness as you raise the antenna above it.
Mike, what headset with microphone are you using, and what are you using to key your radio?
Here you go:
Heil Ham Radio BM-17 Dual headset: heilhamradio.com/product/bm-17-2/
How I record my contact audio: ua-cam.com/video/tOqzZPphE7k/v-deo.html
My headset trigger switch: ua-cam.com/video/b5Wu8BlrSF0/v-deo.html
What's that headphone setup you are using? Or have you switched to something else?
I'm still using the Heil BM-17 headset. Here's some resources on my headphone setup and how I record transceiver audio:
How I record my contact audio: ua-cam.com/video/tOqzZPphE7k/v-deo.html
My headset trigger switch: ua-cam.com/video/b5Wu8BlrSF0/v-deo.html
Heil Ham Radio BM-17 Dual headset: heilhamradio.com/product/bm-17-2/
Add the FC-50 to that ET-891. Just finished hooking mine up, "easy peasy!"
Hello what is a purchase link for the Farradt cloth please? w3jjb
This is the cloth that I am using: amzn.to/4bstu2C
Thanks for the info.
Can i use this method to increase ground plane on my Truck topper, for a permanent vertical antenna setup?
I've seen people with fiberglass roofs on their RVs do something very similar with metal screens to create an appropriate ground plane on the vehicle.
Michael are you connecting the base of the coil mount to the fabric via hard wire, or is the ground connection made simply with the tripod legs making contact ? Thanks !
My antenna base is solid metal and setting it on top of the screen resulted in good contact and continuity. If you are using a non-metal tripod, I'd make a connection with a couple-three jumper wires.
@@KB9VBRAntennas Thanks ! I've had good luck with the screen. The cloth's on order.
Sounds good probably end up getting that eventually I'm just getting back into ham so I'm trying different stuff but I like the idea of the cloth thank you
Thanks again for another great video. The worst part of pota is untangling ground plane wires. I use a copper stake for my sporty fourty and whip so I'll put a large homemade grommet dead center made of 2 pieces of aluminum riveted through the cloth and attach a power pole wire to one of the rivets. I like the idea of tent spikes on the corner. KD2RLB, 73
Do you have a alligator clip to a wire and a connector going to the carpet ?
No. My antenna base makes good contact and maintains continuity between the cloth and the ground side of the antenna.
I have been using this in multiple configurations including very similar to yours. I am a big believer and have had pretty great results. Most importantly, it takes up no space! Thanks for the video! 73 KF0LTY.
What size cloth are you using?
Never mind. Its in the description!
Thank you Michael. You have great ideas and are a great Elmer for Ham radio. Can’t wait to make a contact using your idea.
Oddly enough, I tried this and was unable to get a remotely decent SWR. The lowest I could get on any band was about a 1.9:1, and that took some doing. With 12 16' radials it works like a charm, but with the Faraday cloth, not so much. I may have to mess with it some more and see what I can do, but as of now it won't get the job done.
I've noticed that ground conductivity can have an effect on the window screen or cloth. It may just be the location. Try a different spot and see if you get the same results.
@@KB9VBRAntennas Will do. Thanks!
Well done as always! 73!
Would shape matter? Square or round? Does it make a difference?
Shape doesn't matter, it can be square or round. It's the square foot coverage that you should be concerned about. More is generally better, until you get to 120 square feet. Then the marginal gains greatly diminish. Robert Sherwood demonstrated that in his May 1977 article in Ham Radio magazine. Link to it is in the description found in my original window screen video: ua-cam.com/video/UadUg5H8KO8/v-deo.html
My apologies - is there zero physical connection to the cloth in lieu of the counterpoise?
The base is metal and provides continuity from the cloth to the antenna. If you have a plastic base or tripod, you will need a jumper clip
Can you use the cloth to cover computers and power supplies? It might be effective and blocking RFI for digital operations.
The cloth won't fully attenuate RF signals, but it does lower them. The way RFI gets into computers is often through the cables, so common mode chokes would probably be more effective.
Thank you. I have ferrite beads on all cables and power cords. I might go the route for my computer’s monitor. On some bands it is affected by the transmission from the radio when using an random wire antenna. The transmission is much closer than a dipole on coax.
I thought using bag clips and elastic cord to deploy the cloth..
can any material block ELF? i heard metal shielding might.
Does the vertical antenna that you’re using will it tune in to 10 m?
Yes it will. The antenna is just a 213 inch collapsible whip. you can adjust the whip length to a 1/4 wave for any frequency between 14.000 Mhz and 54 Mhz.