Instrument Preset Conditions (1 - HP 8340B Manual

INSTRUMENT PRESET CONDITIONS
(1)
Press [SHIFT] [INSTR PRESET] and check that the following settings exist. If
any instrument condi¬
tion is
not as shown
below, the instrument requires service.
NOTE:
Press
[SHIFT] [INSTR PRESET]
to eliminate
any frequency
multiplication factor
locked into
the instrument by earlier use of the
SHIFT ALT
function, and
preset
the
instrument (see section three
of this manual set
for
details.)
POWER dBm display
=
0.0
Factory setting, determined by cal constant #56.
A
different
power
level can be
set
by changing
calibration constant
#56
(see Calibration
Constant).
FREQUENCY MHz
display
=
10.000000
START annunciator lit
FREQUENCY MHz
display
=
26.500000 (HP 8340B) OR 20.000000 (HP
8341
B)
STOP annunciator
lit.
Factory
setting.
Calibration Constant #54 should always be set
to
a
value of
26500 for
the
HP
8340B, or to
a
value of
20000
for the HP 8341 B. If
the stop
frequency
is
wrong at instrument
preset,
check this calibration
constant.
ENTRY DISPLAY
=
Blank (off)
SWEEP
block
=
Green LED
flashing
If
the
green LED
is
not flashing, the instrument
is
not sweeping and requires service.
CONT LED
on
FREE RUN LED
on
FREQUENCY MARKER
block
=
All
LEDs off
INSTRUMENT STATE
block
=
All
LEDs off
MODULATION
block
=
All
LEDs
off
ENTRY
block
=
All
LEDs off
LEVELING
block
=
INT LED
on
RF OUTPUT
block
=
RF LED on
The RF output
should be
a
swept
signal, leveled at
0 dBm. This
signal should start at 10
MHz
and
stop at
the maximum frequency of
the instrument.
EXT REF annunciator
=
off.
If
the rear panel
INT or EXT REFERENCE
switch Is in
the EXT position, the EXT REF annunciator
above the
ENTRY DISPLAY
will be on.
A-36
Assembly-Level Service Overall Instrument Troubleshooting
HP 8340B/41B