Leader Electronics Corp. LDC-823A Instruction Manual - page 6
Je
on
both
released, it
e:
and "kHz"
range, the
is
I
it.
,e
case of
rrange indi-
OUTPUT/INPUT Terminal:
Output and input terminal for a clock signal. When the selector-switch
®l
for internal
and external (INT/EXT) is on INT, the internal clock is available to the terminal. Feed a
clock to the terminal externally, when the selector switch
@
is on EXT.
g
Serial number label
I
Power cord
ill
Rubber feet
@
Fuse holder (contains 0.3A fuse)
@
INT/EXT Switch:
Selector switch of an internal clock and an external clock.
®'
With a screw driver, trimmer con trol adjustmen'ts of the reference frequency oscillator can
be made. For procedure, refer to section 6
-
Maintenance.
4.
Operating Instruction
-1-.1
Precautions in use
(1)
In connecting the instrument to the device (to be tested), particularly in an internal
connection, remove all AC power to the device, and remove the cord. After discharging all
charged capacitors, connect the cable for measurement, thus, the danger of an electrical
shock can be minimized. Take the same care in disconnecting the input cable.
(2)
Use AC-power source of LDC-823A at 50 - 60Hz, within 10% of rating voltage.
Caution: Excessively large or small AC voltages may induce erroneous operation.
(3)
In replacing the fuse, use the designated 0.3A fuse.
(4)
Avoid all the severe mechanical shocks to crystal oscillator or fluorescent indicators.
(5)
Reference clock: Wait about 20 minutes for correct measurement until the crystal oscil
lator gets stable in aging.
4.2
Fundamental Operation
(1)
Disconnect the input cable of the LDC-823A.
(2)
Connect the AC power cord to the proper AC power source.
(3)
Set POWER switch to the ON position.
(4)
Set the function switch to FREQ.
(5)
Set the SENSITIVITY selector to 20mVrms.
(6)
Put the GATE TIME Selector at O.lS.
When FREQ. RANGE Switch is 80MHz and 250MHz, Display reads 0.00 kHz and
0.0000 MHz respectively. The GATE indication is lighted for O.lS
while
the gate
is
open, and disappears for O.lS while the gate is closed.
(7)
Set GATE TIME Selector at IS.
Display shows 0.000 kHz at 80 MHz and 0.00000 MHz at 250MHz. GATE indicator re
peats to IS light on/O.lS light off alternately.
(8) Press the lOS GATE Selector
Display shows 0.0000 kHz at 80 MHz and 0.000000 MHz at
250 MHz. GATE
indicator
repeats to lOS light on/O.lS light off alternately .
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