Glad to see you up and about! When I reviewed this one I gave it a few turns around my mast to keep the wind issue at bay. I was surprised at the water results, guess it changed the velocity factor by filling in all the holes!
Fascinating, as always. It is amazing that a 1/4 wavelength of cloth represents (theoretically) from zero to infinity impedance. Finding the 50 ohm point to mass produce an antenna must take trial and error in addition to measurement.
That also looks like a great indoor antenna. It could hang in an attic, a window. a sliding glass door, or as needed on an apartment balcony, deck or patio. I would compare this, the uses and placements with the Dr. Ed Phong DBJ-2. Maybe check the performance of this antenna in a PVC tube.
One thing I would add to the FARA-J-Ant is a lanyard to the Strain relief clip back to the Ant clip base as the clip will be lost over time, also maybe add a Velcro strap to the coax connector attachment point to secure it to the PVC mast Thanks Keith N9QDS
I can predict that it would not work very well. The Faraday cloth is slightly more resistant than copper or wire. And magnetic loops really need a low resistance in the outer loop.
I’ve used flat aluminium for some mag loop designs. I get good restart lower frequencies but I haven’t had as much luck beyond 15m I’m suspecting that the skin effect of a flat conductor is not the same as the skin effect of a cylindrical conductor with the same surface area
It's really intended as a temporary antenna. you'd likely toss the cord over a tree branch and just pull it up. Operate while camping or doing a pota activation, then take it down. If using a mast, just wrap the coax around the mast once.
It's great to see that "Long Covid" has not affected the grey matter at all. Another excellent video. Keep getting better and keep pushing out these excellent videos. 73 VE6HDH
Thanks but it definitely has. It takes me a lot longer to think through things now. And funny you should say gray matter, as there was research showing that after COVID a measurable reduction in gray matter occurs. But each month it gets a little bit easier to think. Being able to get back to work is helping.
I have had it up with just paracord as well. In a different location. No difference in SWR curve on the VNA. It would probably have to be a fairly larger piece of metal like the flashing on the edge of the roof.
The element resistive loss is certainly quite high. But considering its portability, it seems to perform adequately in the dry. Despite Kevin's excellent mod, how long it would last flapping in the wind, is anybody's guess! Might be better in a PVC pipe, but that obviously reduces portability.
The bottom of the antenna will be tied off with a piece of cord, or the coax. So how would you keep it twisted a precise amount? 😉 And actually it was twisted in one of the shots where it was flapping around in the breeze. I think your cargo straps have a lot of tension on them that helps quite a bit. This is not going to have that much tension on it.
I would have just used plastic tie wraps/ zip ties and tie it off at several place to a fiberglass mast. But, I would rather use a roll up 450 ohm ladder line Slim Jim - it will last more than a dozen years, is not affected by rain and gives a better SWR sweep...or at least, my home brew ones do.
This is designed as a portable antenna. So if you just used a zip ties on a mast, you'd be zip tying and cutting the ties every time you put it up when you went to do a park or camping. Let alone having to carry the mast in your backpack. You're thinking outside of the scope of the use case for this.
I think this is convincing me my slim Jim still has a place in my ham-purse. 😂 Though an improvised 1/4 wave ground plane antenna made from coat hangers and a panel mount UHF connector will out perform the slim Jim on 2m!
I would use a TNC connector but to reinforce the board I would wrap it in fiberglass resin right at that spot. And maybe use a pigtail instead of a connector on board ? Just spitballing
it doesn't look like your clip will come off easy. so i don't see the reason for using a foldable cloth j-pole that is longer than a traditional or ladder-line design that would be cheaper and have a wider bandwidth. appreciate the insight though!
good video Kevin! would be nice to see how it might perform on 420-450 as many j-poles work ok as a dual band. Also have you done a video on the window line j-pole. Do you have a link to the plans?? cheers
He also has a separate 70 cm version. Yes I did a video on the slim Jim. You can search my channel for subject I've got quite a few videos. Here's the link. th-cam.com/video/1hG7dva9VIs/w-d-xo.html
Hi kevin. Taxing ur memory. 7 years ago you made a antenna tuner. I was wondering did you use an end fed wire. And do you remember how long u made it. Many thanks. I love ur videos. And glad u r starting to feel better. Again thanx. Jim K1AZ
I think that was a simple L network tuner. They generally do work well for random long wire antennas. I don't remember what I had it hooked up to when I made the video. Length would depend on what bands you want to operate. A decent tuner would get you on 80 m with a wire anywhere from 70 to 100 ft. And probably work well on the rest of the bands up to 10 m.
@@loughkb tks fer getting back 2 me. when I was novice i had a globe chief xmtr and had 130 ft wire right into the xmtr the pi output turned it real super. Many thanx. Will try long wire.
Somebody using this antenna for POTA or SOTA or camping is probably only going to have about a 15 ft run of coax. And they're not going to want to carry heavier coax in their backpack.
$75 for mediocre cloth antenna=NOPE I like ARROW ANTENNAS Yagi Antennas for VHF/UHF much better antenna in ALL ways for less money. Sick of overpriced gimmick antennas by Shameleon and others : (
Ouch. Not sure why you are so bitter. But 1000 sold says it is not a gimmick, also working on some potential military contracts. Regardless I hold no ill will to you and hope you can go out have a coffee and find a loved one to hang out with. I suggest you fill your heart with some happy. I think you may need it. 73
Glad to see you up and about! When I reviewed this one I gave it a few turns around my mast to keep the wind issue at bay. I was surprised at the water results, guess it changed the velocity factor by filling in all the holes!
Fascinating, as always. It is amazing that a 1/4 wavelength of cloth represents (theoretically) from zero to infinity impedance. Finding the 50 ohm point to mass produce an antenna must take trial and error in addition to measurement.
Hope you are doing well Kevin - enjoyed this mate
Thank you for testing this antenna.
Agreed. I love this data to help me make things better.
Nice video, many thanks. Seems like you are doing better, glad to see that!! Robert K5TPC
It always surprises me how far the j-pole design can be pushed.
That also looks like a great indoor antenna. It could hang in an attic, a window. a sliding glass door, or as needed on an apartment balcony, deck or patio. I would compare this, the uses and placements with the Dr. Ed Phong DBJ-2. Maybe check the performance of this antenna in a PVC tube.
Anything in a PVC tube will need its length adjusted to make it resonant. Not saying it is not doable and I should look into this. Great idea.
One thing I would add to the FARA-J-Ant is a lanyard to the Strain relief clip back to the Ant clip base as the clip will be lost over time, also maybe add a Velcro strap to the coax connector attachment point to secure it to the PVC mast Thanks Keith N9QDS
Print a few clips. They're small and quick to print.
I like the velcro idea and might have to give it a try. Thanks for the thought.
i would love to see your Homebrew loop and a fara-J idea ... call it the "Floop"... like a folding loop made from faraday cloth..
I can predict that it would not work very well. The Faraday cloth is slightly more resistant than copper or wire. And magnetic loops really need a low resistance in the outer loop.
I’ve used flat aluminium for some mag loop designs. I get good restart lower frequencies but I haven’t had as much luck beyond 15m
I’m suspecting that the skin effect of a flat conductor is not the same as the skin effect of a cylindrical conductor with the same surface area
Nice work with coax clip. I would add option to fix bottom of the strap to the pole to.
It's really intended as a temporary antenna. you'd likely toss the cord over a tree branch and just pull it up. Operate while camping or doing a pota activation, then take it down. If using a mast, just wrap the coax around the mast once.
Very cool improvement on that! Makes sense. TYFP!
It's great to see that "Long Covid" has not affected the grey matter at all. Another excellent video. Keep getting better and keep pushing out these excellent videos. 73 VE6HDH
Thanks but it definitely has. It takes me a lot longer to think through things now. And funny you should say gray matter, as there was research showing that after COVID a measurable reduction in gray matter occurs. But each month it gets a little bit easier to think. Being able to get back to work is helping.
Try replacing the metal carabiner on your halyard. I have found J Poles very sensitive to any metal near the top end. Thanks for great videos !
I have had it up with just paracord as well. In a different location. No difference in SWR curve on the VNA. It would probably have to be a fairly larger piece of metal like the flashing on the edge of the roof.
The element resistive loss is certainly quite high. But considering its portability, it seems to perform adequately in the dry. Despite Kevin's excellent mod, how long it would last flapping in the wind, is anybody's guess! Might be better in a PVC pipe, but that obviously reduces portability.
Also putting it inside of a PVC pipe would shift the tuning. Ben says he has had one outside hanging up for over a year and it's still in good shape.
Great testing.
😊if you simply twist the bottom of the antenna 180 to 360 degreed the antenna will not flap in the wind.
Trucker trick for cargo straps.
The bottom of the antenna will be tied off with a piece of cord, or the coax. So how would you keep it twisted a precise amount? 😉
And actually it was twisted in one of the shots where it was flapping around in the breeze.
I think your cargo straps have a lot of tension on them that helps quite a bit. This is not going to have that much tension on it.
I would have just used plastic tie wraps/ zip ties and tie it off at several place to a fiberglass mast. But, I would rather use a roll up 450 ohm ladder line Slim Jim - it will last more than a dozen years, is not affected by rain and gives a better SWR sweep...or at least, my home brew ones do.
This is designed as a portable antenna. So if you just used a zip ties on a mast, you'd be zip tying and cutting the ties every time you put it up when you went to do a park or camping. Let alone having to carry the mast in your backpack. You're thinking outside of the scope of the use case for this.
I think this is convincing me my slim Jim still has a place in my ham-purse. 😂
Though an improvised 1/4 wave ground plane antenna made from coat hangers and a panel mount UHF connector will out perform the slim Jim on 2m!
Nope, a slim Jim performs about as well as a 5/8 wave and will outperform a quarter wave ground plane by quite a margin.
Slim Jim always out performs a J-Pole. Mod it into a Slim Jim.
if the black material is like the seat-belt then it's pretty strong....
I would use a TNC connector but to reinforce the board I would wrap it in fiberglass resin right at that spot.
And maybe use a pigtail instead of a connector on board ?
Just spitballing
I did try pigtails but the short traces and them being 90 degrees to the elements helps the antenna perfomance.
it doesn't look like your clip will come off easy. so i don't see the reason for using a foldable cloth j-pole that is longer than a traditional or ladder-line design that would be cheaper and have a wider bandwidth. appreciate the insight though!
You just pinch the tabs and the clip pops right off.
good video Kevin! would be nice to see how it might perform on 420-450 as many j-poles work ok as a dual band. Also have you done a video on the window line j-pole. Do you have a link to the plans?? cheers
He also has a separate 70 cm version.
Yes I did a video on the slim Jim. You can search my channel for subject I've got quite a few videos. Here's the link.
th-cam.com/video/1hG7dva9VIs/w-d-xo.html
Hi kevin. Taxing ur memory. 7 years ago you made a antenna tuner. I was wondering did you use an end fed wire. And do you remember how long u made it. Many thanks. I love ur videos. And glad u r starting to feel better. Again thanx. Jim K1AZ
I think that was a simple L network tuner. They generally do work well for random long wire antennas. I don't remember what I had it hooked up to when I made the video. Length would depend on what bands you want to operate. A decent tuner would get you on 80 m with a wire anywhere from 70 to 100 ft. And probably work well on the rest of the bands up to 10 m.
@@loughkb tks fer getting back 2 me. when I was novice i had a globe chief xmtr and had 130 ft wire right into the xmtr the pi output turned it real super. Many thanx. Will try long wire.
👋🏻👍🏻Yo buddy!
Hi Charlie.
Hell-o Kevin! Hope all is smooth. 🛵
Rj58 loses nearly 11db per 100ft
at 70cm. Rj58 should only be used for hf.
Somebody using this antenna for POTA or SOTA or camping is probably only going to have about a 15 ft run of coax. And they're not going to want to carry heavier coax in their backpack.
$75 for mediocre cloth antenna=NOPE I like ARROW ANTENNAS Yagi Antennas for VHF/UHF much better antenna in ALL ways for less money. Sick of overpriced gimmick antennas by Shameleon and others : (
Ouch. Not sure why you are so bitter. But 1000 sold says it is not a gimmick, also working on some potential military contracts. Regardless I hold no ill will to you and hope you can go out have a coffee and find a loved one to hang out with. I suggest you fill your heart with some happy. I think you may need it. 73
@@VE6SFX_HamRadioRookie Bitter Truth, Overpriced Common Antenna, Keep It.
I always carry my arrow yagi in my back pocket... 😅