Hi there,
I have a very old phone box in which I incorporated a GSM shield. The box is fully metallic and I am using an external antenna. I was hoping the box would act as a nice signal shield and that I would get no GSM noise at all, regardless the quality of my cabling, but I am getting a lot of it and I have to wiggle cables in order to improve that.
How could I improve the shielding? I think my box is not connected to the mass, should I start by doing that as to complete the ground shielding idea?
Any tip much appreciated
Thanks 