I have been looking for instructions for making a sleeved dipole antenna for 2.4 Ghz for use on my DIY RC receivers. I haven't found anything that clearly specifies the all the specific lengths of each part of the antenna, I imagine because there are so many variables.
Although I don't really have the kit needed to evaluate an antenna design, I have been experimenting and this is what I came up with. I am looking for feedback if I should adjust any lengths, and if someone with the equipment to properly test this antenna would like to help be out by testing it, that would be wonderful.
Desired center frequency 2.425 Ghz
Coax: RG-178 (velocity factor .69)
Sleeve length: 26mm
Element length : 28mm
Coax feed length: 170mm (2 wavelenghts x velocity factor)
The sleeve was made by folding the braid back and flooding it with solder. The primary element ends up with 2 layers of heat shrink (over the dielectric) and the sleeve ends up with one layer. Pic attached showing 3 different stages of the build.
My tuning was done with my Taranis RC transmitter which has a RAS indicator which is supposed to be SWR. I had the same good reading at 27, 28, and 29mm, so I took the middle length.
For reference, here is my RC receiver project:
https://github.com/soligen2010/RC_RX_CABELL_V3_FHSS. I have made a number of receivers that work well, but when I try to send telemetry from the RX back to the TX, it is way less reliable that the signal from TX to RX. I am thinking the best antenna I can make would help this.
Thanks