SUBJECT:

Two trouble-shooting items for the signal quality.

ANSWER:

1. Radio signal quality is poor

(1). Make sure the distance between two wireless stations
(Ad-HOC mode) or between the wireless station and the AP
(Infrastructure mode) is not too far.

(2). Wireless station/AP Placement Guidelines

(2.1). AP placing

- Please always place the AP as high as possible, in
as open an area as possible.
- Avoid placing the AP close to metal objects (e.g.
file cabinets, metal cubicles, metal ceiling/floor/wall...etc.)

(2.2). The adapter's signal path is blocked by metal casing, e.g.
metal filing cabinets.

Arrange the antenna position to get the best radio signal quality
Radio waves reflect or refract from buildings, walls, metal
furniture, or other objects. This could result in performance
degradation due to the fluctuation of the received signal.

(2.3). There is a device using the same 2.4GHz radio
frequency the NDC uses, e.g. microwave oven.

Arrange the position of wireless stations or AP to be far
enough away from any RF interfering devices. (10 meters min.
is advisable)

[Placement Tools]

NDC includes a Station utility program to help users
find the best location in which to place the AP or the wireless
stations relative to the location of the stations.

(1). Start the AP.
(2). Allow a wireless station to connect the AP or another station.
(3). From the station, run the NDC Station Monitor RF
Signal Quality program
(4). Move the AP or the station and its antenna to find the
best signal quality.

2. Radio signal quality is black (zero)

Please read the following possible causes to check step by step:

(1). The NIC has not been worked/initialed. (check in the Adapter
Property of the NDC utility.

[note] If some network devices(wireless NIC) or services
(including the 3rd-party PCMCIA service software) have not
been started or initialed completely before you logon a Windows
NT machine, you will see an error message to say 'Can't find
the NDC adapter' when the NDC utility starts. Just
disregard this message (click OK to close it). Close the
NDC utility at somewhere on the screen and then re-run the
utility from the Startup menu once all network devices and services
start completely. The utility will find the NDC adapter
and run normally then.

(2). The domain name of all wireless stations are not the
same one.
(3). The domain name of all wireless stations are the same
one, but the lowercase/uppercase of all domain name
are not the same completely. For example, one domain
name is set to be 'Workgroup', but another is set to be
'WORKGROUP'. That is not correct.
(4). The distance between two wireless stations (Ad-Hoc) or
between the wireless station and the AP (Infrastructure mode)
is too far.
(5). Make sure there is no any wireless inteference device around
your NDC wireless station and the AP.
(6). If your operating system is Windows NT4.0, be sure you
didn't install the Service Pack before installing the
NDC driver and the Network components. If you did
that, please reinstall(uninstall and then install) the Service
Pack after installing the NDC driver and the Network
components.
(7). One among the wireless adapters (ISA, PCMCIA
cards) is bad in RF(radio frequency) module.