Radio/Microwave
Alarm
MicroAlert is an alarm that
you wear like a pager that will alert you to the presence of radiofrequency and
microwave radiation. The MicroAlert is important protection for all pacemaker
users, those sensitive to RF radiation from TV or cell phone broadcasts, or
anyone who lives or works in the presence of microwave or RF hazards. Can even
be used to detect audio and video transmission from concealed bugs or the
unauthorized use of cellular phones!
MicroAlert will respond to
as little as 0.1 ?W/cm? in highest sensitivity mode. When MicroAlert is moved
closer to the source of RF radiation, the chirps will become more frequent, and
will become a solid tone when exposure is high. Responds to frequencies from 500
kHz to 3 GHz, although response is not flat over this range. What this means is
that at any given setting, the threshold will vary with frequency. Note: This is
not a high precision meter. Sensitivity information is only a guideline.
The beeping alarm threshold
can be adjusted from no threshold (constant beeping regardless of radiation
exposure), to to a maximum of about 10 microWatts/cm?. It is intended to be an
alarm for cell phones, cell towers, microwave ovens, surveillance bugs, and most
RF transmitters.
Only 1-5/8" x 2-1/4", the 1
oz. MicroAlert uses one Lithium coin cell #2032 which should last about 3 years
with normal use. Includes convenient belt clip.
MicroAlert - Model 2 Instructions
The MicroAlert Alarm detects
radio and microwaves, causing the device to produce and electronic "chirping"
sound / beep when the field strength detected is higher than a level that you
have adjusted / set the instrument to.
Locate the "power" switch on
the top surface of the device, just above the words "OFF ON". Slide this
recessed switch to the "ON" position. You should hear a single beep / chirp when
this has been done, which indicates the battery is good. The unit is now
working. The small black knob marked SENSITIVITY, which is on the right face of
the box, is normally set at the factory to its center position. Notice the line
that is indented into the small black knob. The "center position" means that
this indented line points toward the arrow next to "NORMAL", which is on the
label of the MicroAlert. If you rotate this knob clockwise, it will increase the
sensitivity.
Counterclockwise rotation of
the knob will decrease the sensitivity. The "center position" represents a
certain sensitivity, though the sensitivity depends to some extent on how the
MicroAlert detection face is positioned. If held up in the air with your fingers
on the lower half of the case, with your fingers beside or below the word
"MicroAlert 2", this "NORMAL" sensitivity is about 5 microwatts / cm2. This is
the strength (or technically, the power density) of the radio / microwaves that
will cause the unit to just begin to beep. The beeps will repeat at about 4 per
second if the average power density is just at this threshold of 5 microwatts /
cm2. If you move to an area where the power density is higher, the beeping will
become more frequent (as frequent as 20 beeps per second). Above about 10
microwatts per cm2, the beeping becomes a solid "always-on" tone.
CALIBRATION
PROCEDURE
If the MicroAlert does not
perform / operate as described above, when set at the two most clockwise
positions shown on the diagram, calibration is necessary.
The MicroAlert should beep
even when it is shielded (by being cupped in your hands), if the knob is set to
the "Maximum clockwise travel" position, however it should not beep when set to
the ".1 (3.5)" position if it?s cupped in your hands.
To calibrate the device,
unscrew the single screw on the backside of the MicroAlert (the small
screwdriver is included with your MicroAlert especially for this procedure).
Rotate the black knob to its most sensitive position, at maximum clockwise
travel. Inside the MicroAlert, you?ll notice a copper rectangle with a hole in
it. This is the antenna. Stick the screwdriver through the hole so you can
rotate the small round control under the hole. Rotate this round control so that
the MicroAlert beeps a few times a second. (This beeping should be heard after
you take out the screwdriver and cup the MicroAlert in your hands.) Then turn
the black knob to the ".1 (3.5)" position shown in the diagram. Now the unit
should not beep when cupped. Of course, it?s easiest to do this test in an area
that seems to already have fairly low radio / microwave signal. That is, an area
where there?s not much difference between the microwave field the MicroAlert
picks up whether you hold it upright or cup it in your hands.
BATTERY
Battery life is typically 3
years if it isn?t beeping more than about 5 minutes a day. If you don?t hear a
beep when you turn it on, replace the battery. Also as the battery voltage
drops, the beep volume will be softer / quieter. The weak battery does not
affect the sensitivity level, but if the beep sound becomes too quiet to be
useful to you, then you should consider replacing the battery.
It uses an inexpensive
lithium "2032" (CR 2032) type 3 volt battery, available from any store / site
which has batteries for sale. To replace it, unscrew the center screw and follow
the directions printed inside the MicroAlert on the green board. You need to
push down on the white plastic round tab (looks like a cul-de-sac) with a few
pounds of force until you hear a click, then the battery will be at a slight
angle. Pry the battery out with the screwdriver. If you accidentally put the new
battery in backward, it will not harm anything, but the unit will not work until
you put the battery in with the "+" side facing up. After sliding the battery
into position, push down on the battery on the side which is sticking up the
most, so that it will sit flat in the holder. Replace the cover of the
MicroAlert Alarm.
ADDITIONAL
MICROALERT ALARM OPERATING INFORMATION
Avoid strong static electric
sparks around the MicroAlert. These might shift the sensitivity level and could
require you to calibrate it. For 6 MHz radio waves, the unit is about half as
sensitive as it is in most of its range. This means you should multiply the
numbers in the diagram by two if you know the wave is 6 MHz. It is less
sensitive at lower frequencies than 6 MHz. At 5 MHz, multiply by 3. At 2 MHz,
multiply by 7. At 1 MHz, multiply by 20, and at 500 KHz, multiply by 50 (that
is, it is 1/50 as sensitive). General maximum public exposure to microwaves is
10 microwatts/cm2 in several European countries. In the US, the maximum
allowable is much higher, at approximately 600 microwatts/cm2, for typical cell
tower frequencies (the maximum allowable exposure depends slightly on the actual
frequency of the microwave field in question). The MicroAlert does not detect
600 microwatts / cm2, though it can be used to check European Standards, which
are within it?s range of detection. In most areas in US cities, the level is
below 10 microwatts / cm2.
One-Year Limited
Warranty
