preps
Results 1 to 9 of 9

Thread: Figured I'd try my hand at antenna building...

  1. #1
    Join Date
    Apr 2013
    Location
    Michigan
    Posts
    19
    Thanks
    1
    Thanked 23 Times in 9 Posts
    Downloads
    5
    Uploads
    0

    Figured I'd try my hand at antenna building...

    And what better to start with than a 1/4 wave center loaded large coil?



    The overall length is 58", and the overall element length is 54. The coil is 5 turns, 3.75" dia by 3.75" long. Hope my math came out right. The insulator is 3/4" SCH80 pvc, with 1/2" NPT threads tapped into the ends. The bottom of the coil is soldered into a 3/8" hole drilled in the side of the threaded adapter. The top of the coil is soldered into a 3/8" hole drilled into the side of a 1/2" NPT to 5/8"OD compression fitting (1/2" copper pipe is 5/8" OD). After the coil was soldered in place, I ran a 5/8" drill bit though the compression fitting, cutting the stub of copper from the coil off flush with the inside of the fitting, and removing the stop lip inside the fitting, allowing the top half of the antenna to slide freely in and out up to 4 inches for tuning purposes.

    Guess we'll see if it works. If not, at least it looks cool.
    Last edited by anickode; 04-29-2013 at 04:21 PM.

  2. The Following 3 Users Say Thank You to anickode For This Useful Post:

    Beercanman (05-23-2013), Moonchild 747 (05-20-2013), Super Slab (05-06-2013)

  3. #2
    Join Date
    Nov 2011
    Location
    in the planet
    Posts
    628
    Thanks
    185
    Thanked 206 Times in 102 Posts
    Downloads
    10
    Uploads
    0
    very nice , I like it . how heavy is it ?

  4. #3
    Join Date
    Apr 2013
    Location
    Michigan
    Posts
    19
    Thanks
    1
    Thanked 23 Times in 9 Posts
    Downloads
    5
    Uploads
    0
    I'd estimate maybe 3 lbs... Very light, all type m Copper tube.

  5. The Following User Says Thank You to anickode For This Useful Post:

    High Voltage Mobile NJ (04-29-2013)

  6. #4
    Join Date
    Dec 2011
    Location
    RICHMOND VA.
    Posts
    715
    Thanks
    402
    Thanked 251 Times in 167 Posts
    Downloads
    0
    Uploads
    0
    looks to have potential

    how did you do the threads to allow it to screw into a typical 3/8x24 mount ?

  7. #5
    Join Date
    Aug 2012
    Location
    Round Rock, TX
    Posts
    394
    Thanks
    94
    Thanked 196 Times in 100 Posts
    Downloads
    7
    Uploads
    0
    Have you tried it yet? It looks great!

  8. The Following User Says Thank You to Silverado 996 For This Useful Post:

    BOOTY MONSTER (05-11-2013)

  9. #6
    Join Date
    Dec 2012
    Location
    Killadelphia
    Posts
    23
    Thanks
    11
    Thanked 3 Times in 3 Posts
    Downloads
    0
    Uploads
    0
    I like new toys...give me a price after you test it out and build some more
    ~Super Slab~

  10. #7
    Join Date
    Apr 2013
    Location
    Michigan
    Posts
    19
    Thanks
    1
    Thanked 23 Times in 9 Posts
    Downloads
    5
    Uploads
    0
    Well, I tried it out, and it seems to work nicely. The compression fitting tuning works like a charm, but you have to make sure not to snug it too tight, or the ferrule will be crimped down on the copper, making it immovable.

    My house is in a lousy spot for transmitting from. It sits at the very bottom of the lowest spot within probably 10 miles of here, and I'm not allowed to put up a tower, so I threw together a quick tripod, stuck it on my roof, stretched out 4 102" ground radials, and had a go. I managed to get it down to 1.2 SWR with minimal effort. Probably could get it lower, but I was tired of climbing up and down.

    With 4 watts, I was able to make contact with a friend of mine 27 miles due north. He said my signal was faint, but audible. I could hear him loud and clear, as he's pushing 300 watts through an Antron 99 on a 30 foot mast.

    The design could definitely use some refinement. The biggest issue I have is putting together the top end of the insulator, because I'm currently required to thread the compression fitting in, and then solder the coil into the side. I'm thinking the best solution is either a slip fit, instead of threaded, or a bolt-on coil, instead of permanently fixed.

  11. The Following 3 Users Say Thank You to anickode For This Useful Post:

    BOOTY MONSTER (05-11-2013), High Voltage Mobile NJ (05-11-2013), Silverado 996 (05-11-2013)

  12. #8
    Join Date
    Aug 2012
    Location
    Round Rock, TX
    Posts
    394
    Thanks
    94
    Thanked 196 Times in 100 Posts
    Downloads
    7
    Uploads
    0
    Awesome! Thanks for the report. How long did it take to fabricate the antenna? How much will you be charging if someone would like one? How much would you charge if you made one with a shaft length that measured 30" from the bottom of the coil to base / mount and an overall length of 5' to 6' with the stinger? I'm running a 2 pill amp, do you think it will handle it? Have you done a test with linears yet?

    Thanks

    Added::::

    How much $$$.$$ do you have tied up in this project in materials??
    Last edited by Silverado 996; 05-16-2013 at 09:54 PM. Reason: Added:::::
    Silverado 996 back in the woods and I'm gone!
    * Cobra 29LXLE *
    * Ranger 2970N2 * 5' FireStik FS-5 *
    * Uniden BearCat 12 watt spearker *


    "It is not the strongest of the species that survives, nor the most intelligent, it is the one most adaptable to change, that survives"

    - Charles Darwin

  13. #9
    Join Date
    May 2013
    Location
    Georgia
    Posts
    53
    Thanks
    5
    Thanked 26 Times in 17 Posts
    Downloads
    0
    Uploads
    0
    Nice antenna...Great Job on the build...
    de 747 and I'm clear...

    "He who controls the electromagnetic spectrum controls the world..."

Visitors found this page by searching for

None

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •