6
AL-NSM Networx Signal Meter & AL-NSG Networx Signal Generator User's Guide
USEFUL TIPS
Hand Placement
When holding either the
NSM
Signal Meter
or the
NSG
Signal Generator
, the human body itself can have an
affect on the radio signals. Therefore, we recommend
holding either unit from the
bottom left corner
(see pho-
tos) when measuring radio signals.
Unit Placement
To optimize results, it is crucial that the
NSM
or
NSG
(depending how they are used), be located / held within
the inside ("protected" side) of the door (the actual loca-
tion of the Networx lock internal radio). For example, if
the
NSM
is hung on the outside ("unprotected" side) lev-
er and the door is closed, the readings will be unreliable.
Lanyard vs Reusable "Mounting Putty"
Both
the
NSM
Signal Meter
and the
NSG Signal Gen-
erator
are equipped with an inert nylon lanyard in-
tended to be used to hang the unit from a lever handle or
other secure object. In addition, the
NSG
comes with
reusable adhesive mounting putty that can be used to
temporarily mount the unit to a wall or door, as needed.
Radio Signals and the Human Body
Radio signals bounce off of (or are absorbed by) almost
everything, including the human body itself, having a
positive or negative effect on the radio signal. There-
fore, we recommend to enable the desired Mode and to
walk several feet away from the unit to obtain an aver-
age result (see "
Averaging Signals
" below). Best results
are obtained when the
NSM
or the
NSG
is hung or af-
fixed, motionless, on or from the intended installation
location (i.e. the lever handle of the intended installation
door or the mounting location of the Gateway).
Averaging Signals
When attempting to evaluate radio signal quality, it is
important to average the data provided by the
NSM
, re-
gardless of which Mode is used. High traffic environ-
ments, radio interference, etc. may easily cause signal
fluctuations, therefore it is recommended to take multiple
readings over several minutes to ensure the results rep-
resent median values.
Advantage of Integral Sounder
The integral sounder on the
NSG
provides simultaneous
audible feedback during data transmissions. In addition,
the opposite (loss of sound) provides immediate recogni-
tion of "null" areas where the signal is absent.
For example, in Mode 1, if the
NSM
is chirping and then
suddenly silences at a specific location, that location
may represent a null location, where the radio signal is
lost entirely. In addition, in Mode 3, it is often helpful to
use the sounder as an immediate warning of radio inter-
ference.
NSG Physical Dimensions
It is useful to note that the exact dimensions of the
NSG
is identical to a standard Networx Gateway (models
AL-
IME
,
AL-IM80211
,
AL-IMEPOE
and the
AL-IMEPOEP
).
Therefore when an optimal mounting location is found
using the
NSG
, simply mark its side mounting hole tabs
to greatly simplify the mounting of the permanent Gate-
way.
DBM Chart
Readings are provided in dBm
units for those more familiar
with using standard radio com-
munication terminology. The
chart at right is provided to as-
sist in visualizing dBm units,
especially the concept of how
signal levels increase (grow
stronger) as they move up the
scale closer to zero.
This concept also applies to
noise levels: As readings move
up to zero, the noisier (worse)
the noise levels become in the
area.
0
-10
-20
-30
-40
Increasing
Signal
Decreasing
Signal
dBm reference (1mW)