Tuesday, March 8, 2011
It is very simple to build and you can tune it in your shack room (simulating a holyday installation in a Hotel...) using an antenna analyzer (I used my Autek VA1) but I think that you can do it also with a SWR meter and a general coverage rtx using low power.
Start with the ends some cm longer (ex. 400 mm instead of 330 mm) and then cut both sides until you have the resonance in 20m band.
Remember that the frequency is not critical because then you will "tune" the dipole with the Antenna Tuner Unit.
Thanks to author Guido, ik2bcp / iu2r / ab9dg
The material used is a thick copper wire. Take copper wire about 20cm and bend at 5cm. make 5 turns of the wire on a screw or any thing that make the winding looks good. Ok then stretch the turns about 3mm wide. now make few turns on the other end.Place it on your EVDO antenna as shown in the figure. see the difference in Signal strength.
You can use this trick to get good signal in indoor from any mobile broadband networks like BSNL, MTS MBlaze etc.