LRS-455-EU Data Transceiver Users Manual
LUM0032AA Rev A
Version 1.0
1
About FreeWave Transceivers
FreeWave transceivers operate in virtually any environment where RS232 data communications occur. A
pair of transceivers function as a 9-pin null modem cable. If the FreeWave transceivers are to be used in
an application where a null modem cable is used, such as communication between two computers, then
the FreeWave transceivers can be connected directly. If FreeWave transceivers are to be used to replace
a straight-through RS232 cable, then a null modem cable must be placed between the transceiver and
the DTE instrument to which it is connected.
Choosing a Location for the Transceivers
Placement of the FreeWave transceiver is likely to have a significant impact on its performance. The key
to the overall robustness of the radio link is the height of the antenna. In general, FreeWave units with a
higher antenna placement will have a better communication link. In practice, the transceiver should be
placed away from computers, telephones, answering machines and other similar equipment. The RS232
cable included with the transceiver usually provides ample distance for placement away from other
equipment. To improve the data link, FreeWave Technologies offers directional antennas with cable
lengths ranging from 3 to 200 feet. When using an external antenna, placement of that antenna is critical
to a solid data link. Other antennas in close proximity are a potential source of interference; use the Radio
Statistics to help identify potential problems. The Show Radio Statistics page is found in option 4 in the
Main Menu. An adjustment as little as 2 feet in antenna placement can resolve some noise problems. In
extreme cases, band pass filter may reduce the out-of-band noise.
WARNING:
Do
not
connect the LRS-455-EU series radio
to power without terminating the antenna port to a load.
