I bought a secondhand Xperia P, but the average signal strength it receives is -90bpm, and keeps on disconnecting when using 3G network. The interesting thing is that I have an another cellphone that gives proper signal strength at the same location with the same cellular network.
beside that I observed that when I'm outta home, I guess that in air pressure it can't catch any signals. It a lot when I'm on the roof because there air is high.
