Amazing portable solution, Michael. I activated K-2991 yesterday and it worked well. I didn’t even run the little jumper. I just set WRC tripod on the on the screen and it ground through the legs. Thanks for the great idea.
The antenna is a 213 inch extendable whip. I adjust the length for 20 meters and above to make it a 1/4 wave. At 40 meters I use the Wolf River Sporty Forty coil and the whip fully extended.
While the vast majority of your viewers know you meant the metal/aluminum window screen, there will be the random person who grabs the fiberglass screen and then complains you're faking it. I will be storing this idea up for several possible applications and thank you for sharing this idea
Lol. I started a local 2 meter low power simplex net to get people familiar with not using repeaters. One fairly distant contact was using mag mount on metal rail. Barely worked. Suggested some kind of piece of metal plate? for ground plain? He dragged out one of wife’s cookie sheets. Still noisy but readable. Then… suggested pointing long end of sheet in my direction. God dam. Almost 5x9. Needless to say it was a valuable lesson to all the newbies. Getting back to the fun part of hobby.
UPDATE: I just bought a roll of screen. Report will be coming after this afternoon's activation! “Any antenna that will get you on the air is a good antenna.” Words to live by. Nice activation. UPDATE 2: AMAZING!! With my batch of radials the SWR never was lower than 2.4:1. With the roll of screen and a jumper wire the NanoVNA yielded 1.4:1 SWR!!! Thank you for the idea.
@@seeharvester True, very true. But not everyone can afford to dump $$ into antennas that we can learn to homebrew for half or less the cost. Unfortunately, homebrew takes practice so the first few aren't as good.
@@Adui13 I agree! Years ago I built my first antenna by following plans in the ARRL Antenna book. It was a 2 element horizontal yagi mounted at about 24 feet on a length of heavy wall pipe. Rotated it with a jerry rigged garage door opener contraption that would have made Rube Goldberg proud.
@@seeharvesterA bad antenna in a good location often beats a good antenna in a bad location. It's one of the reasons portable operation is so attractive IMHO.
My grandpa was a ham radio operator and he had a whole bedroom dedicated as his radio room. He had an 18 foot powered antenna on his roof that needed repair, he was in the hospital dying from emphysema (after a lifetime of smoking three packs of Winston a day) and his dying words to my old man were ''Did you find somebody to fix the antenna?''. That old dude was literally 'die-hard'.
How does that tripod stay upright in the wind you had? The Wolf River coil is on my bucket list! Oh by the way Michael; I recently acquired my GMRS license. I purchased one of your J-poles for GMRS; as well a very nice elderly Ham/GMRS guy gave me a whole lot of GMRS equipment; 5 handheld radios; whip antennas for them, a mobile 25 watt GMRS radio; a slim Jim antenna and a few other accessories. He refused to take a dime from me. He knows I’m very radio active on both sides so he knew I would use the equipment given. Sadly he has been diagnosed with 3 different types of cancer and wanted to make sure the radio equipment would get used! I am both honored and moved that radio people are so great!
It's a weighted base for a tear drop or feather flag, commonly seen outside of businesses. amzn.to/3qn8cNj. It swivels, which can be a pain, but really does a great job of holding the antenna upright on a breezy day.
I used chicken wire under a 43' vertical with great results. It was still perfectly fine after 5 years of use. Space was restricted so I had 30' in one direction and 15' at right angles. I used several ground connections (to the chicken wire) at the base of the antenna. I'll try window screen for portable - thanks for the experimental work!
Did you discover any effect of RF directivity with the direction you laid out the window screen ground plane? If you did, maybe two rolls of window screen laid out in an "X" pattern might help. Might be an interesting research topic. Nice video and thoroughly enjoyed it! Good balance of theory, research, and field operation with QSO numbers at the end. 73s! DE AG4KN- John
I did not notice any directivity. Looking at a satellite image, I estimate that my screen was laid out roughly north-south. I would then expect the bulk of the contacts to be east west. But using a vertical antenna complicates things and the QSO map of contacts is quite similar to what I receive with evenly spaced radials. Interestingly, the article from 1977 that I referenced used a variety of configurations including a cross. The author found that when you use a long piece of screen that approaches the resonant length of your fequency, directivity starts to occur. Laying the screen in a cross helps mitigate the directivity.
Yea, back in the 80's, when it seemed like; everyone had C.B. radios, I had a Dodge Polara all metal body, and had my whip antenna mounted directly on the rear of the car metal bumper. If I wanted more range/distance of my radio transmission, I remember I would point the front end of the car towards the direction of the receiving person. (Using the total length of my car to take advantage of the largest ground plane, which was my vehicle!) If we were traveling on the same road, it would be easier to utilize the largest ground plane of my vehicle, and could communicate longer distances at 180° from each other, as opposed to the receiver person being at the 90° direction of which way my vehicle was pointed. Semi Truckers had a larger ground plane utilizing the 53' trailer, as their extended ground plane, and could send/receive greater distances!
@@KB9VBRAntennasthis statement indicates a misunderstanding of what’s going on here. There is no change in directivity. Reducing ground losses with a radial field increases RF current, but has zero affect on the omni-directional signal.
I realize that this video is several months old, but I only recently had the opportunity to give this a try. While my SWR was 1.2:1, I did discover that if the WRC tripod is not on the screen, the SWR goes through the roof even with a jumper. But when moved back, the SWR returned to the previous reading. In light of this, using the Magic Carpet is so much easier to deploy then wire radials. Thanks once again Michael.
NEATO!!! I've been messing with EZNEC using 12" square brass screen for both a capacitive hat on top of a 25' vertical and 3 more 12" squares on the ends of three 3' ground plane radials with EXCELLENT results both calculated SWR and Launch Angle. I've yet to build a prototype, but using steelcore copper wire allows the whole thing to roll up into a 12" square only about an inch thick in a backpack. I expect to solder the screens to the steelcore diagonally to minimize the screen wire-to-wire currents so corrosion won't cause intermodulation. Let's keep chasing this and see where this goes! 73 -- NW7T
@@ronlaborde7528 There is the dissimilar metal corrosion issue connecting to aluminum. I use Ideal NoAlOx from Home Depot to grease up any copper-aluminum connections. The competitor Ox-Gard from Gardner-Bender works well, too!
I just tested this with 2 24x84 inches screens with hamsticks on a nail in the ground. I could easilly bring SWR to 1. It was really interesting to see how the orientation (bearing) of the screens affected the SWR. They seem quite sensitive to the ground so just turning them around can help. Spacing between them too. If you're chasing SWR 1.0, these are all factors to consider. In normal operation, it's easy to get down to 1.2 quickly and be happy. I talked to a guy in the South of France from the South shore of Montreal (Canada) on 10m with a FT-818 50W amp.
Thanks Michael, this is terrific. Using WSPR was brilliant - since you realize that having great SWR is not "everything" - but to know is the signal getting out? I greatly appreciate these practical tips in action. 73, K7KS
That is a really cool solution. I have limited space for radials but I can lay a metal window screen right across the lawn. Would be perfect for portability. I have seen some Stainless Steel mesh rolls for $120 that are 100 feet x 48". Cut the mesh in half, lay one at 90° to the other and you have a potential radial ground plane for 75m. 73!
Back in the 70's, the college I attended formed a ham radio club. In our first few weeks we didn't have an antenna so I volunteered the use of my 14AVQ. We were not allowed to dig holes so we mounted the antenna to the chain link fence, worked great.
Awesome video! Thanks for putting this together and doing the WSPR tests to back it up! For 15m, it was probably just going really long and skipping over most hunters.
This will be fun to try. I'll be interested to hear how the screen ages. I vaguely remember an old report that with chicken wire, wire to wire conductivity goes away over time, presumably due to oxidation between the wires. That report was also for a permanent installation, so there was plenty of weather exposure to support corrosion. With the portable regularly redeployed application, the corrosion might get scrubbed off as part of the unrolling/re-rolling process. You also have way more contact points than with chicken wire. I've also got some parks with rock ledge here in New Hampshire, thus very low ground conductivity, where it would be good to repeat the screen versus radial tests.
Chicken wire will corrode if buried or left on the ground for an extended period of time. If you want to use a screen on a permanent install, most people recommend something with welded wire connections. For temporary and portable use, the window screen is fine. It will take a very long to oxidize to the point that it provides a poor ground connection. By then I can replace it with a new piece of screen.
So today I tried this for the first time and all I can say is WOW!! Using the Gabil Radio Antenna with the MFJ-1979 whip and a 4'x4' square piece of screen, I was able (using the Rigexpert) to measure all of the QPR frequencies (CW ) in the 40, 30,20,17,15,12 and 10M bands and all of them fell between 1.38 and 1.95 SWR. I also wrapped the edges of the screen with duct tape which makes handling much easier and it keeps it from fraying. I did not even have to use the 40M extension to nail a 1.65 SWR on 40M. I was using the KX3 with these and really did not have to hit the tune button for these qrp frequencies. Thank you for showing us this really worth while way to go instead of all those crazy long radials. Just for everyone's information, here were my settings on the whip. These are the number of segments extended on the 1979. 10M - 3 1/2 12M - 4 1/4 15M - 5 1/4 17M - 7 20M - All the way extended. Gabil adjusted all the way closed. 30M - All the way extended. Gabil adjusted 3.1 up. 40M - All the way extended. Gabil adjusted 6.56 up.
I activated 5 local parks yesterday using this setup, but with two window screens for a larger and more square footprint. It worked great! So quick and easy to put up and take down. 20m has been rough pretty much all week and I got slightly better results with this setup than the arrangements I used earlier in the week. I did find that different parks (different underlying ground conditions) seem to want different arrangements of chokes for best results, but I am far from an expert. I just used what seem to work best at that park, at that time. I also use one of those swooper flag bases for the weight of it. Things often get pretty windy around my neck of the woods... Or beach, as the case may be... For less than 20 bucks, it is worth trying and seeing if it is practical for you. I'm instantly a fan after yesterday.
The same can be said for traditional wire radials lying on the ground. There are always slight impedance variations based on the underlying ground composition and moisture content.🙂 KZ9V
I like using WSPR to test antennas too! I use it casually from my mobile phone with acoustic coupling. I set the transceiver to VOX and place the mic next to the phone. Then I trigger the app. Bingo! It's fascinating to see my 5 watts reported by stations monitoring from wherever the antenna reaches under the current conditions. Great for comparing different antennas and setups.
Yes, WSPR is a terrific tool for antenna tests using very low power. I used just 1 watt for this video and easily garnered 50+ signal reports from all across the U.S. KZ9V
A friend of mine when he was having a house built, before he put in the lawn, he put down two twenty pieces of chain link fence and then put the sod on top of that. 73. Bill KZEDX
Hardware cloth wouldn’t add much as its surface area that is more important than thickness. Plus hardware cloth is pretty stiff stuff so it will be harder to work with.
I gave this a try with some backyard portable. I used a WRC tripod, an MFJ-1979 expandable whip, and a 36"x 72" roll of aluminum screen. I checked the SWR on several different bands. Here are the minimums: 10-meter 1.17, 12-meter 1.02, 15-meter 1.18, 17-meter 1.2, 20-meter 1.08, 40-meter 1.7. The results were fairly flat across the bands with the exception of the 40-meter band. I'm looking forward to a field test the next time I do a POTA activation.
Those are great numbers and I'm sure the screen will work great for you. I'm starting to hear lots of excellent results from others using the screen in the field.
Those are great numbers. Keep in mind that when you are adjusting a 1/4 wave vertical, there is a slight difference between antenna resonance and a 1:1 VSWR (50 ohms). A 1/4 wave vertical is actually about 37 ohms at resonance, so the VSWR at true resonance will likely be close to 1.3:1. KZ9V
Nice video and idea! I like the way you tested it. My version, I use 4 cheap Harbor Freight tape measures as radials. Easy to deploy, take less packing space than wire mesh. Need to check effectiveness though. SWR numbers are good.
Adding on to John Davis question about directivity, I have always heard that a vertical with radials on one side will tend to transmit better in that direction and also TEND to null in the other direction. Should you do this again, it would be interesting to put the antenna on one end of the strip of window screen and see if you can, to some extent, direct your propagation. Thanks for the interesting video.
What a great video, I recall a Silent Key family member doing the same thing in our backyard in 1978, with the window screen on the ground. I was eleven years old at the time, He always use to tell me on setup, "lean towards the screen" If I recall correctly, we had an old 80-10m radio (Astro 200) and an old Yaesu FT-301D Good times!!! Again, wonderful video thanks for bringing back beautiful memories!!! Maybe will lean that way this year with POTA, cheers 73.
Software modelling various arrangements on my relatively conductive ground here suggest that a ridiculous number of very short radials well under 1m long would yield high efficiency. So your screen approach might work very well for me too.
Ich prozessiere schon lange mit Grund(Earthground)Blechen herum.Manchmal geht schon eine CB Rundstrahlantenne mit einem Blech bestimmter Grüsse gut Indoor ab.Der Der zappelte dann kaum noch!🐒👍😯😎😎💞Das kann sich aber bei Regenwetter sofort verändern und zwar zu schlechterer SWR!
Thank you for this video and many others! They have increased my confidence and knowledge as an operator. I was super exited about this setup for small footprint POTA activation. I picked up an aluminum screen this morning and made a counterpoise jumper similar to yours. I'm using a camera tripod, the WRC tripod/antenna plate, a Shark 20M hamstick, and a 36x84" aluminum screen. I was able to get to < 1.5 SWR across 20M SSB with this setup. One interesting note: I found that my SWR went way up when my feed line, 25' RG8X coax, was laying on the screen. When the feed line contacts the ground a couple feet from the screen, the SWR goes back down. It would be interesting to know if anyone else has noted a similar phenomenon. Hopefully this helps another experimenter.
I think what's happening is that your coax laying on the screen is inducing common mode currents which is increasing your SWR. I haven't witnessed this yet, but I try to orient my coax so that it minimizes contact with the screen.
What I love about experimenting like this is the screen manufacturers will be thinking holy hell must be a huge increase of bugs this year, our sales have gone up 25%. Not having a clue it’s because of HAM
I'm not a CB or HAM guy. This just came into my feed. I found it interesting. There's been a lot of movement in the electronics fields in terms of surface mount technologies, affordable prototyping and small batch production with circuit boards and even faceplate production. I wonder if that's creating a renaissance in shortwave and other hobbies.
Actually, amateur radio is bigger than it's ever been. I don't know the numbers over the past few decades. But I doubt that the recent prototyping/surface mount stuff has been much of a factor in stoking interest in ham radio. That said, I'll bet that amateur radio operators are utilizing the technologies you mention, even though it's a minority of hams that actually build circuits.
@Not Given it's even easier than ever to produce circuit boards. Electronic hobbyists can make equipment that rivals pros in options and performance. You can literally send off runs of circuit boards in the teens and it's still very affordable.
@@fakshen1973 Yes, having been in the field since the '70s, and still currently designing electronics, I'm aware of that. but thanks for posting your comment. I hope more people get interested. We're living in a golden age, aren't we?
This is an excellet idea, thanks for the video. I am president of the Georgian Bay Amateur Radio Club (GBARC) in Owen Sound, Ontario, Canada. When doing public demonstrations there are often limits on how we can setup an antenna. Working in a parking lot of other hard surface or where space is restricted can be problematic. Using screening as you've demonstrated really does open up options for possible antenna deployments. Finding ways to solve problems by experimenting is a fun part of the hobby.
Before I watch your video, did you do this little experiment of yours with and without the screen and then … make the comparison? Or did you just use the screen to see how well it works? Now I will watch the video and edit this comment when I’m done. …… Yeah,, I think I’ll just stick with single long wire ground radios. Thank you. 🤭🤭🤭
Very interesting. I'd like to see a comparison to a typical permanent antenna ground radial installation with 30+ radials vs the 4 radials most people set out for portable antennas. At what point does it become cost effective to use screen in lieu of wires for a permanent installation? How much screen has to go down to take the place of 30 wire radials 33 feet long?
Years ago I got ahold of some stainless mesh screen for free that was a little too beat up for whatever its previous use was, It was about 4 feet wide and 30 feet long and I had 3 of them. I crossed them over each other and slapped a 5-btv in the middle and it did work better than my 16 each 33' radial field on the analyzer and on the air but on the air really isn't a measurable thing but I did talk from Washington to Florida pretty often after the mod and never reached Florida previously to the screen.
I always liked your videos but this is the one that made me decide to subscribe. How interesting and fun! Now I want to try it too. Thanks for all you do.
The antenna is a 213 inch extendable whip. I adjust the length for 20 meters and above to make it a 1/4 wave. At 40 meters I use the Wolf River Sporty Forty coil and the whip fully extended.
This is wise. I've thought about capacitive coupling to ground before, but haven't gotten around to testing it yet. Thanks for the great video on that. 73 de LA6NCA
After seeing this I grabbed a piece of mesh chicken wire fence out of the shed; about 4x4 and have been using it ever since. I don't even use a jumper because the wolf river tripod legs make the contacts. I'm getting great SWR and making contacts with the 891. Thanks for that tip!
I also have tried this by your inspiration & is a blast in set up as well as Ground Plane. Great idea! Puts my 4 30' tape measures to shame. I thought that was a great idea till I tried this. Thanks buddy! Brian Clintonville
I have always wondered about steel grain bin roofs. There are a ton of these steel bins going to the salvage yards. They are conical shaped and when disassembled then laid flat on the ground would resemble a windmill fan. I would think this would work as an excellent field of radials for a vertical antenna but of course for a permanent installation. I am going to try this someday in my farm yard. Not the best for portable as It would probably get the attention of a park ranger in a POTA setting…
This the antenna set-up with my HTX-100 Transceiver at the Ham in the Park I used. I used a MFJ Enterprises Inc.-1622 2 meter to 40 meter Antenna. Normally I would used the Counterpoise wire to ground the antenna. But I used the my "Magic Carpet" as the Ground Plane. It worked great! The "Magic Carpet" is a pre cut 36"x48" aluminum Window screen, I got at Hometown Ace Hardware, I connected to the antenna. One can get the Window screen just about anywhere they sell hardware.
I worked at an AM radio station that built a new tower, about 3 decades ago, the tower was located on a newly constructed parking lot and the ground was a huge grid of welded wire under the parking lot concrete. It worked and still works really well. the key for a permanent situation is having all connections welded because unwelded screen breaks down and actually creates interference.
Get's me thinking about using aluminum duct tape and maybe on a more sturdy backing that's cost effective and would stick good. Maybe some sort of plastic with extra plastic on the ends for securing to the ground or using weights on? Neat work and device! Thanks for sharing! I'm off in my own mind controlled world trying to get that systems situational awareness capabilities out and recovering when I can doing whatever doesn't perturb those things that are definitely something alien foreign creeps un-American as it gets.
What about metallized plastic films aka emergency blankets? Another idea would be an aluminized fabric like the one used for tent covers as a heatshield. Did you already consider these?
Would be interesting to see or test if you place the antenna to one end of the screen, do you have any directional properties or gain in the direction of the long end of the screen?
the screen rolls up nicely and is easy the travel with. I would use the 19ga 1/2” square galvanized if I were going to bury it in the yard. just don’t buy the vinyl screen… DOH!
Hey this is an awesome video. Love how you showed it quick in the beginning and then really got into it with kz9v and his experiences too. I’ll be applying this in my endeavors. I think I’ll be able to apply this to my satcom ability too. Keep up the videos!
Thanks for the video Michael. I have a Wolf River antenna that I haven't had a chance to use the field yet. One of my concerns is stretching the gound wires out in a public area. The screen idea seen like a great solution to my dilemma. W2GJF
Interesting concept. To take this a step further, do you think that a metalized Space Blanket would enhance the transmission similar window screen? A folding Space Blanket would be easier to transport than a rolled screen.
Great video! I did this yesterday at a POTA in Connecticut and made 140 contacts on 20 meters. 2 in Italy and 1 in the Netherlands. SWR was 1.4 on my ft-891. Pict of setup is on my QRZ page. Again, great video! 73, KC1PIV
At HF frequencies, chicken wire screen will be adequate, and I think less expensive. If you do stay with window screen, I would suggest putting the screen on the back of some thin carpeting so anyone walking up would not be punching holes in the screen with their heels, etc. The other thing, use short braid with clamps to connect, rather than long wire, to keep inductance down.
I also research the article you pointed out. This may be the answer I am looking for. I had to take my antenna down I had 12 radials on my vertical that sat on top my patio roof. The HOA was not pleased. Maybe just a flat piece of screen laying on the roof as the counter poise will satisfy them. I’ll let you know. Thanks again.
Hello Michael, Great experiment. I believe there is ONE more element to explore: Screen mesh connectivity (or lack of...) As the screen ages and oxidizes, I believe it will start to lose conductivity. - and efficiency . So my opinion is this is great for temporary use with frequent replacement of screen (which is CHEAP !) You might be able to counteract the loss of connectivity with additional jumpers between the mesh and coax ground ? I want to try this out! 73 de kg5rk
So I ran an interesting test. I setup my WRC on the ground with no radials attached or screen near it. It had been setup for 20M (my last use) and when I tested the SWR with no radials of any kind attached. It measured a bit over 3.2 I then unrolled the aluminum screen and placed it below the WRC (did not attach the screen to the antenna base). The SWR dropped to 1.07. I then attached the screen using a jumper (like Michael shows in his video) and it dropped to 1.05. It does not appear that physically attaching the mesh to the antenna base is needed. It works like a steel plate below a magnetic mount on a 2M vertical.
isn't the screen galvanized steel? or aluminum? also small diameter single wires in an RF grounding system are known to have high impedance to RF and a braid or flat foil works far better. Connecting the screen directly to the feedpoint and elevating the screen would be optimal
@Kevin Scott That's really interesting. Was your coax cable lying directly on the screen material? There may have been sufficient capacitive coupling between the coax cable shield and the screen material to make the RF connection.😀 That's sort of how magnet antenna mounts work on vehicles.👍 KZ9V
@@davewhite7679 It was, and you are correct, that is likely what was happening. I was very careful to make sure the legs on my MegaPod were not touching the screen, but the Coax feeds straight down from the center of the MegaPod and it did lie on the screen on its way to my antenna tester.
@Kevin Scott I was talking to Michael about your experience earlier today. This is another unexpected twist. He's going to try to replicate your results with no DC connection wire between the coax shield and the mesh screen. 🙂
I like this.I’m in an HOA here in Orlando. I’ve been looking at the flag pole antenna. I could screen my front yard and sod over it. I would like to see what different size screens would make if any
The type of screen material won’t matter. Overall surface area is more important than than hole size. If you are going to bury it, it use something like hardware cloth. Chicken wire works but the holes are woven and not welded so they tend to rust and cause noise
If you are going to use a flag pole anyway . Just bury several of those copper grounding rod around the flagpole . Place the copper rods radially outward hurried in the ground . Keep the ground watered . The copper grounding rods would make a great ground counterpoise . Instead of capacitively grounding . You are directly grounding to the ground .
Chicken wire works great. You can get a 25 foot roll 2 feet wide for about 15 bucks. Much great ground coverage and way more durable at a fraction of the cost. Awesome performance! 73 kf0alt
This is excellent, Michael, thanks! Truly a brilliant idea. I'm going to try this as well, both for POTA and for my base station. I figure I can just lay it out in my back field where my vertical is, perhaps even in a cross pattern. Which makes me wonder whether there would be any additional benefit at all over a single strip of screen? Well, once the snow's gone here (Green Mountains of VT) and the ground is workable, I'll try to lay some screen flat on the ground so the grass can just cover it. (It's not a field that gets mowed anyway.) Can't wait to try it out, cheers!
The article I referenced has some good information on different deployment variations and sizes of screen. You can put two long pieces in a cross configuation. As the screen gets longer, it can cause a bit of directivity. A cross pattern can mitigate that.
I don't think there will be any benefit from actually overlapping the two pieces/sheets of screen material, if you were to form an X pattern by criss-crossing 2 longer sheets. To maximize contact (opportunity for increased capacitive coupling) with the ground (and also more potential reflectivity of the RF off the ground), you would likely be better off laying the two screen pieces side-by-side and not overlapping. If forming an X, you would get greater surface area against the ground by using 3 pieces (one long and 2 short--one on either side of the long piece), as long as there were still good electrical connection back to the shield side of the coax.
I worked with Unattended Ground Sensors that were buried for concealment. Most of these devices operated between 138 to 153 MHz, FSK Modulation @ 2 watts to deliver a 29 to 36 Bit message in 30 Millisecond pulse. The Antennas were Piano Wire Thin, 19'', Made from Beryllium Copper, also made for concealment. In certain locations dependent of the geologic makeup we had no problems with transmissions reaching either a repeater or monitor being used. However!! In areas where I did have problems with TX to RX when burying the sensor we would slide a piece 2 inch piece of insulator over the antenna and then slide an 8'' x 8 '' piece of copper screen over the Antenna before burying. It solved our transmission problems in many areas... When it comes to UGS you do not pick the area, the situation does. so you have to make it work... So I can see how your Screen works Great and I appreciate your video. I am Retired now and just passed my Technician Test this week'.. so looking around these videos.... Take care and Thank You
After viewing your video, I wanted to try this out. I didn't have window screen, but I did have a 3' x 4' piece of chick wire... I did the same tests that KZ9V did and got the same results he did. I compared it to my 53' EF and was pleasantly surprised at those results. Thanks again for this video! de WA6OEF
My 20 meter full size 1/4 wave vertical has the ultimate ground plane, the 14 ft by 70 ft steel and aluminum shell of my mobile home bonded to Earth by 18 hurricane anchors with steel straps screwed into the ground in 1981. It's series fed by a balun ferrite transformer that raises its 12 ohm impedance up to 50 ohms which makes my highly modified Tentec Hercules II very happy. Few kilowatt stations have a bigger signal. The field it creates is very intense.
Same concept as a mag mount VHF/UHF antenna on a cookie sheet. This is just a bigger cookie sheet. Ah the true spirit of amateur radio alive and well!!
Been thinking about this a lot lately. My first experiment is to simply close the radials with a circumference wire. I would guess, that a closed loop of ground wire, would be more sensitive to RF flux. Or maybe it electrically looks like a really thick wire ?
I did CB back in the 1970's but got worn out pretty quick with idiots and their echo chambers, 1000 watt linear amps and talking like Cledus Snow. Almost like their IQ would drop 50 points as soon as they keyed the mic. I recently discovered the world of GMRS and was dazzled by what can be done with 5 watts and a repeater. Ham radio doesn't interest me (for now) I think that world would suck me into something so expensive it would be worse that drag racing. I've come to the conclusion that antennas are everything.
What a great idea! Simple and portable. Thanks for the video! To go further down the antenna rabbit hole and NOT that it would be portable at all, but I wonder how this would work with the screen in a frame, off the ground with the vertical antenna above the screen. Wire-elevated radials seem to work better than wires on the ground...73!
I believe that when you elevate the ground screen, it will function more like a capacitive hat and less like a counterpoise. This may take some modeling and testing to see if the hypothesis is true, though.
Michael, I always enjoy your videos and the sharing of fun, easy things to try. Go figure, I just bought a 500' roll of bright orange-coated wire to make radial packs. I think I'd rather try this instead spending the time laying out the 24 radials I was going to make! I also will take along a handful of ground cloth staples to keep the screen from crawling around. One thing I didn't in this video was a beer!🍺
Instead of letting the scrap man have your old cooker or fridge take them apart and use the metal panels as a ground plane. I buried an old metal bed frame with cooker and fridge panels on top extending down my tiny garden under the paved area. Unfortunately I got QRM from broadband internet so can't hear much with S8 noise on h.f. so never really got to try them. I dug down and after ten years being buried most of the enamel paint was still good with only spots of rust. Maybe when copper cables are phased out in favour of fibre optic the QRM will go and I can try again. G4GHB.
