I like this video, very good demo. I have find it is hard to find the parts local to build antennas some times a old TV antenna can be find but clean and rework takes time but you are recycling the parts (This is good thing! :) )
Sadly MCM Electronics went out of business in late 2017, the parent company Newark Electronics was sold to a competitor Avnet. I loved MCM for my parts and toys!
Great build idea, I can only find that donor antenna from the USA and it works out at £68 that’s $90 shipped, so that’s a no go, but yeh a great project if I can find one local, thanks for sharing.
$90, yikes!! Definitely defeats the point of the project. I was bummed when the retail source, I cited closed up shop after posting this video. If you do find a local source, please drop me a line. So the video description can be updated, & make it relevant again. Jim(KW4KD)
jmhrvy1947 Surething,. I think this type of Antenna is mainly for the US market, I’ve never see a FM antenna that big in England, maybe half that size and that’s big over here. But the design is still sound for cobbling one up from bits of aluminium tube n stuff.73 Barnie.
Thanks for the video. Would you consider moving all the elements closer in order to reduce boom length? The models i've looked at show 4 elements could be reduced to a boom length of approx 44".
I suspect it's possible. The Antenna's original boom length didn't present a space/load issue for me. The antenna program predicted reasonable performance figures without having to change the director spacing(s). So like video says, I kept it. But if a shorter boom important, then plug in your dimensions into the program, and see what kind of numbers you can get. I wouldn't be surprised, with a few "tries", that you'll find a combination that exceeds in some way what's shown in the video. Have fun. Experimenting IMO can be one of the most rewarding parts of this hobby. Tnx, Jim(KW4KD)
@@jmhrvy1947 One more Q: when measuring the folded dipole to achieve equal halves, do I measure from the middle of the bend up and around to the middle of the opposite bend? Or, measure only the top and bottom straight sections? Thanks
@@phurla1 Good Question. Technically, I think, your first method is the correct way. But to be honest, I treated it as a simple ratio & proportion problem. New length = Original Length x ( New Freq/Original Freq) . Where "Original Length" & New Length were tip to tip measurement(s). Figured, given the frequencies & lengths involved, that would be close enough. For me, it worked out pretty well.
@@jmhrvy1947 Found a one element FM antenna on line almost exactly like the one you used. Followed each step, soldered rg6 to board, added one element, and cut to 145 Mhz. Field tested today. 1.1 to 1 at 145.9. Ran simplex over 20 miles voice and digital with excellent results. Only trouble I had was closing the circuit box back up due to diameter of rg6. Folds up nicely for field use. Thanks, again.
What were the elements constructed of? Also do you have better pictures of the balun connections. Also do you think it possible to change out the type F to SO 239?
The elements are the original elements that came with the antenna, they were just cut down to resonate at 2 meter frequencies. As for using a different connector. it might be easier to replace the "F" connector with a BNC type connector than an SO239 style. But in terms of weather resistance my guess is the "F" type is superior to the BNC. Thanks for the comment and you interest in this project
I doubt it, as the orientation does not impact the build dimensions. But as mentioned in the video, spacing was changed to allow for vertical mounting.
The software I reference in this video was included as part of the 22nd edition of the ARRL Antenna handbook. And that's how I came by it. After receiving your comment, I found these two links: www.arrl.org/files/file/Product%20Notes/Antenna%20Book/YW.pdf www.preparedham.com/forums/index.php?topic=1286.0 The first link describes software in greater detail than I did, and the 2nd, may get you to the software itself. IMO The book by itself is a bargain, and is a sure fire way to get the software Thanks for your interest in the project & GL
No.. Not at least starting with the antenna I started with. Going from the commercial FM frequencies to Two Meters results in an antenna that is smaller than the original. Going down in frequency (11 meters) would result in antenna that would be bigger than the original... Hope that makes sense Thanks for the comment. I'm betting there are others out there with the same question
I like this video, very good demo. I have find it is hard to find the parts local to build antennas some times a old TV antenna can be find but clean and rework takes time but you are recycling the parts (This is good thing! :)
)
Thank you.
Excellent! Very well made video... Thank you.
Sadly MCM Electronics went out of business in late 2017, the parent company Newark Electronics was sold to a competitor Avnet. I loved MCM for my parts and toys!
Didn't know that. Wondered why I hadn't seen a flyer from them. I'll miss them too. Thanks for the comment.
Newark has 346 in stock as of 03.25.21
Great build idea, I can only find that donor antenna from the USA and it works out at £68 that’s $90 shipped, so that’s a no go, but yeh a great project if I can find one local, thanks for sharing.
$90, yikes!! Definitely defeats the point of the project. I was bummed when the retail source, I cited closed up shop after posting this video. If you do find a local source, please drop me a line. So the video description can be updated, & make it relevant again.
Jim(KW4KD)
jmhrvy1947 Surething,. I think this type of Antenna is mainly for the US market, I’ve never see a FM antenna that big in England, maybe half that size and that’s big over here. But the design is still sound for cobbling one up from bits of aluminium tube n stuff.73 Barnie.
Great video, I wondered if that antenna would be a good to make a 2 meter antenna
Thanks for the video. Would you consider moving all the elements closer in order to reduce boom length? The models i've looked at show 4 elements could be reduced to a boom length of approx 44".
I suspect it's possible. The Antenna's original boom length didn't present a space/load issue for me. The antenna program predicted reasonable performance figures without having to change the director spacing(s). So like video says, I kept it. But if a shorter boom important, then plug in your dimensions into the program, and see what kind of numbers you can get. I wouldn't be surprised, with a few "tries", that you'll find a combination that exceeds in some way what's shown in the video. Have fun. Experimenting IMO can be one of the most rewarding parts of this hobby.
Tnx,
Jim(KW4KD)
@@jmhrvy1947 One more Q: when measuring the folded dipole to achieve equal halves, do I measure from the middle of the bend up and around to the middle of the opposite bend? Or, measure only the top and bottom straight sections? Thanks
@@phurla1 Good Question. Technically, I think, your first method is the correct way. But to be honest, I treated it as a simple ratio & proportion problem. New length = Original Length x ( New Freq/Original Freq) . Where "Original Length" & New Length were tip to tip measurement(s). Figured, given the frequencies & lengths involved, that would be close enough. For me, it worked out pretty well.
@@jmhrvy1947 Found a one element FM antenna on line almost exactly like the one you used. Followed each step, soldered rg6 to board, added one element, and cut to 145 Mhz. Field tested today. 1.1 to 1 at 145.9. Ran simplex over 20 miles voice and digital with excellent results. Only trouble I had was closing the circuit box back up due to diameter of rg6. Folds up nicely for field use. Thanks, again.
@@phurla1 Thanks for the report. Always enjoy hearing how one project spawns another.
What were the elements constructed of? Also do you have better pictures of the balun connections. Also do you think it possible to change out the type F to SO 239?
The elements are the original elements that came with the antenna, they were just cut down to resonate at 2 meter frequencies. As for using a different connector. it might be easier to replace the "F" connector with a BNC type connector than an SO239 style. But in terms of weather resistance my guess is the "F" type is superior to the BNC.
Thanks for the comment and you interest in this project
Hello. Do the dimensions change for horizontal orientation?
I doubt it, as the orientation does not impact the build dimensions. But as mentioned in the video, spacing was changed to allow for vertical mounting.
if you posted some pictures or a link to pictures that would be most useful
excellent!
Please post a link from ARRL's web site. Thanks and for the Software
The software I reference in this video was included as part of the 22nd edition of the ARRL Antenna handbook. And that's how I came by it.
After receiving your comment, I found these two links:
www.arrl.org/files/file/Product%20Notes/Antenna%20Book/YW.pdf
www.preparedham.com/forums/index.php?topic=1286.0
The first link describes software in greater detail than I did, and the 2nd, may get you to the software itself.
IMO The book by itself is a bargain, and is a sure fire way to get the software
Thanks for your interest in the project & GL
Can you make one for 11 meters fox hunt.
No.. Not at least starting with the antenna I started with.
Going from the commercial FM frequencies to Two Meters results in an antenna that is smaller than the original. Going down in frequency (11 meters) would result in antenna that would be bigger than the original... Hope that makes sense
Thanks for the comment. I'm betting there are others out there with the same question
thats 75 ohm coaxial cable