PTI Wireless System Changes
In September of 2011 the PTI Wireless system underwent a change in the types of components used. The transmitters, repeaters and receiver all changed from the "FA" type to the "EchoStream" type. These two types are not compatible with each other and cannot be mixed. (The "Head End" unit that connects to the RS-485 network remains the same).
Externally, the two types of transmitters look exactly alike. Internally they are different. Refer to the images below to see the difference.
The new "EchoStream" transmitter has the battery located in-between the two circuit boards, which are about 1" apart.
The older "FA" transmitter has the battery located on the side of the circuit board that is away from the other board, and the two boards are about 1/4" apart.