Home made antennas.

Discussion in 'FPV Systems' started by mozquito1, Aug 12, 2017.

  1. mozquito1

    mozquito1 Summer's over, where's my thumbless gloves

    IMG_20170812_163756474-1024x575.jpg
    The antennas I made in about an hour a piece. For less than £4 each.
    The only thing is they have not been tested yet. IMG_20170812_161110934-1024x575.jpg
    Apparently using 10 awg you do not have to have a wave trap. But it does have to be 0.4mm from the plate.
    IMG_20170812_164147297-1024x575.jpg
    So this is what I come up with for 0.4mm off the ground plate.
    IMG_20170810_184441094_HDR-768x1367.jpg
    I will have to test it on all channels & bands to see which is best. Same withe the omni. I have not got a printer so I had to dig on the info to draw a former template for 5.8ghz. If anyone wants the info I'll post it.
     
    Gyro Doctor and GJH105775 like this.
  2. mozquito1

    mozquito1 Summer's over, where's my thumbless gloves

    If you know what a wavelength is then you will know what a quarter wavelength is & this diagram will make sense. PhotoPictureResizer_170812_231537619-1024x768.jpg
     
    Gyro Doctor and GJH105775 like this.
  3. mozquito1

    mozquito1 Summer's over, where's my thumbless gloves

    d= diameter of wire
    L=length of the coil
    S=1/4 wavelength 11.8mm
    D=diameter of former 17.5mm
    a=space between coil & reflector plate
    R=reflector size 40-50mm
     
    Jackson, Gyro Doctor and GJH105775 like this.
  4. Gyro Doctor

    Gyro Doctor Electronics Tech for 45 years

    ... :rolleyes: ... Well done Moz !
    Now just toss those puppies on a spectrum analyzer and check the frequency response.
    Oh, and some polar coordinate graphs of the radiation parameters would be nice too. ;)
    (nyuck nyuck ... oh, I wise guy heh?) :p
     
    mozquito1 likes this.
  5. mozquito1

    mozquito1 Summer's over, where's my thumbless gloves

    You seen how much they cost. :eek:
     
  6. Gyro Doctor

    Gyro Doctor Electronics Tech for 45 years

    Yep, they ain't cheap, and it's not like there's a whole lot to 'em anyway !
     
    mozquito1 likes this.
  7. Jackson

    Jackson USA member at large

    Gyro Doctor and mozquito1 like this.

Share This Page