EXTECH
INSTRUMENTS
3
CTH10A
‐
en
‐
GB_V2.3
10/15
Operation
Getting
Started
Open
the
rear
battery
compartment,
insert
three
(3)
‘C’
type
batteries
observing
correct
polarity
and
then
close
and
secure
the
compartment
cover.
Press
the
Reset
button
(using
the
tip
of
a
paper
clip
or
pin)
in
order
to
initialize
the
meter.
Automatic
Time
Setting
After
inserting
the
batteries
and
resetting
the
unit
as
described
above,
the
clock
automatically
scans
for
the
WWVB
time
signal
and
the
icon
flashes
on
the
LCD.
flashes
Indicating
now
is
receiving
WWVB
signal
turns
on
Indicating
signal
received
successfully
disappears,
Indicating
signal
reception
failed
The
clock
automatically
synchronizes
with
the
WWVB
radio
signal
every
day
at
2am
to
maintain
accurate
time.
If
synchronization
with
the
signal
fails,
the
signal
icon
disappears;
the
clock
then
attempts
to
synchronize
with
the
WWVB
signal
at
3,
4,
and
5am.
The
clock
can
be
set
to
scan
the
time
signal
manually
by
holding
the
button
(B4)
for
3
seconds.
Note:
If
a
manual
scan
is
attempted
with
the
signal
icon
showing,
the
signal
icon
will
disappear
and
the
manual
scan
will
have
to
be
attempted
again.
Each
reception
takes
about
5
minutes.
If
reception
fails,
scanning
stops
and
the
signal
icon
disappears;
the
scan
then
repeats
on
the
next
full
hour
(e.g.
if
a
scan
failed
at
8:20am
a
scan
will
be
tried
again
at
9am).
Stop
scanning
by
holding
“
”
button
(B4)
for
3
seconds.
Note:
Buttons
will
not
function
while
scanning
for
the
WWVB
time
signal.
Manual
Time
Setting
In
the
time
display
mode,
hold
the
“MODE”
button
(B2)
for
3
seconds
to
enter
the
Clock/Calendar
setting
Mode.
Press
“+”
(B3)
or
“
‐
”
(B4)
button
to
adjust
the
setting
and
press
the
“MODE”
button
(B2)
to
confirm
each
setting
and
move
to
the
next
setting.
The
setting
sequence
is
as
follows:
Hour,
Minute,
Second,
Year,
Month/Day
sequence,
Month,
Day,
DST.
Notes
:
1.
All
setting
modes
will
automatically
exit
after
15
seconds
of
inactivity.
2.
Press
and
hold
the
plus
or
minus
button
for
faster
scrolling
of
digits
while
editing.
3.
For
Time
Zones:
The
default
setting
is
zone
“P”.
Hold
“+”
(B2)
button
for
3
seconds
to
change
to
another
zone
“P”
“M”
“C”
or
“E”
Pacific,
Mountain,
Central,
and
Eastern.
4.
DST:
When
the
DST
function
is
activated
(Daylight
Saving
Mode)
“DST”
will
be
shown
on
the
LCD.
Set
‘DST’
as
described
in
the
Manual
Time
Setting
section
above.
