I was randomly browsing and ran across a DIY 2.4 Ghz antenna, so I decided to build one. I started with an old Belkin router and added a N female pigtail to it as I have loads of N connectors laying around.



The first antenna started out as a FSJ4 (Andrews superflex) jumper. It was cut to length and the outer conductor and dielectric removed.



Then coils were added at the appropriate length for 2450 Mhz, as it is the middle band for 2.4 Ghz routers. The coils are the same O.D. as the I.D. of the PVC and the PVC coupler is a nice tight fit around the base of the DIN connector. It will need a PVC cap and then all glued to make it weatherproof.



Here it is being tested, the range until it drops is about 400' in open air, and I can walk 150' to the other side of the shop (as in the waves traveling through all the steel of the building) and still get a bit of signal. Nothing impressive, but it was a quick build and I skewed from the plans quite a bit.



Next I decided to make both a collinear and a yagi. The collinear was a LDF4 Jumper that was cut into sections and then 10mm of outer conductor and dielectric was removed from both ends, then the 8 pieces are soldered alternating connecting the inner and outer conductors to each other. This puts RF on the outer conductor and I need to install toroids on the feeder in order to use it, so I'm not sure of performance... The yagi is a piece of square carbon fiber with holes drilled for the elements. The element length and spacing determines the frequency of the antenna, so they must be very accurate. The elements are 1/8" brass rod and the driven element is a piece of copper wire.



The yagi was quite impressive! I walked out as far as I could without crossing the street (about 400' or so) and was still getting 3 out of 4 bars on my phone, a speed test showed 19.3 MBps download speed, but my phone limits around there anyways... I'll take a computer across the street later on and see if I can transfer the full 50 MBps and then test out the full range.

The tape is from an antenna building related accident.


Here is where I was standing, the antenna is right inside the overhead door with the lights on.