Palm Treo 700p User Manual page 342

Phone
Signal Strength Is Weak
Become familiar with low coverage areas where you live, commute, work, and
play. Then you will know when to expect signal strength issues.
If you're standing, move about 10 feet in any direction.
In a building, move near a window. Open any metal blinds.
In a building, move outdoors or to a more open area.
Outdoors, move away from large buildings, trees, or electrical wires.
In a vehicle, move your Treo device so that it's level with a window.
My Treo Device Won't Connect to the Mobile Network
Try the suggestions in the preceding section for weak signals.
Turn off your phone and turn it on again (see "Turning Your Device's Phone On
and Off" on page 55).
Perform a soft reset (see "Soft Reset" on page 314).
If you have an active DUN session (that is, you are using your device's phone
as a modem), terminate the session (see "Using Your Device's Phone as a
Modem" on page 118 or "Using Your Device as a Wireless Modem" on
page 173).
The Other Person Hears an Echo
Try decreasing the volume on your Treo device to avoid coupling or feedback
on the other person's end. This applies to both the speakerphone and the
earpiece.
330 Section 7A: Help