Settings; Instrument Preset, Partial Preset; Power; How Turning The Power On Affects Instrument Settings - HP 8642A Operation And Calibration Manual

Model 8642A/B
Descri ption
Procedures
POWER
Operation
INSTRUMENT PRESET, PARTIAL PRESET
Signal Generator settings can be reset by switching the Power from standby to on,
selecting Instrument Preset, or by selecting Partial Preset.
The instrument is turned on by switching ( POWER) from STBY to ON. When it is
turned
all,
the Signal Generator goes through a sequence of internal checks. If the
instrument encounters no problems, it sets itself to the initialized state that is set up
wlth InstruI1le nt Preset.
If any failures occur during the power -up self check,
hardware mcssages arc queued up to be selected with the (MSSG ) key
(If the
messages encountered cannot be found in the Operating Messages operating
instruct ion beginning on page 3-177, refer to the Service Manual.) The power-up self
check takes approxima tely
20
seconds.
Instrument Preset is selected with ( IGSTR
PRPETJ
This function sets the Signal
Generator to the initialized state described on page 3-138.
Partial Preset is selected with PARTIAL ( [SBTFT] ( INSTR PRESET) ) and enables
you to set the instrument to a known state without losing some frequently used
settlllgs. This function maintains some current instrument settings, turns off others
(while maintaining their last -selected values so they can
be
selected "on" with the
(OFF ON I
key), and resets other settings to Instrument Preset values. Because Partial
Preset does not reset the entire instrument state, it takes less time thall does
Instrument Preset. (For example, Partial Preset may take only
a
few hundred
milliseconds while Instrument Preset takes approximately two seconds)
How Turning the Power On Affects Instrument Settings
Switching the
CfJOWER-]
switch from STBY to ON changes the instrument settings to
those listed for Instrument Preset (refer to "How Instrument Preset Affects Instrument
Settings" on the following page) plus the following:
<>
HP-IB is set to local mode.
l)
The Signal Generator is configured to an unaddressed condition.
~ The HP-IB address is set to that of the internal switch if RAM memory has been
lost. (RAI\I memory could be lost, for example, if the battery loses its charge.) (Refer
to HP-IB Address on page 3-8.)
• If RAM memory has been lost, the sequence function is set to a start register of 00
and a stop register of 50.
3-137