User`s guide

13
Either an HP-HIL keyboard can
be used for entering the
command (plugged into the
front of the HP 70004A
display/mainframe), or the
“typing aids” key under the
Utility menu of the USER keys.
As the program is stored on the
card, the LED to the left of the
card will flash intermittently.
If there is a problem with the
mass storage definition, refer to
chapter 3 of the HP 71500A
Instrument BASIC User’s
Guide (70820-90055). After you
have successfully stored the
program onto the memory card,
slide the write-protect switch to
the outside position. This will
prevent accidental erasure.
Loading from a memory
card or disk drive
The second method of
downloading the program is to
use the mass storage features of
the HP 70004A mainframe.
Press the DISPLAY key under
the display, followed by Mass
Storage on the left, followed by
msi on the right. Select
MEMORY CARD if the program
has already been stored to a
memory card (see above), or
HP-IB disk if loading from an
external disk drive (connected
to the HP-IB connector on the
back of the mainframe).
Using an HP 9122 or HP 9133
disk drive as before, make sure
that the HP-IB ADDRESS is set
to 0, the UNIT NUMBER to 1, and
the VOLUME NUMBER to 0.
The next step is to actually load
the program. The easiest way
is to use the MENU keys of the
HP 71500A. Press the MENU key
below the display, followed by
States (page 2 of 2) on the
left, followed by mass storage
(more 2 of 2) on the right.
Next, use the up/down stepkeys
to highlight the file to be loaded.
Then press LOAD FILE on the
right. After the file has loaded,
it will automatically run.
It is possible to have the program
automatically load and run
when you power up the analyzer,
by having an “auto-start” file
stored in addition to the group
delay program. The HP 71500A
will look for the auto-start file
on whatever mass storage
device was last used. If you are
using a memory card to store
the group delay program, use
the procedure described
previously to download and copy
the program AUTOST from the
floppy disk to the memory card.
See page 3-8 of the HP 71500A
Instrument BASIC User’s
Guide (70820-90055) for more
information on auto-start files.
Menu Overview
The group delay personality
provides the user with a custom
menu structure, tailored to the
group delay measurement
application. These menus are
accessed under the USER
softkeys. Note that when the
group delay program is running,
successive presses of the USER
key will toggle between the
personality softkeys and the
IBASIC softkeys. The personality
softkeys are structured
similarly to the standard MENU
keys in that the left-hand keys
are fixed, while the right-hand
keys change according to which
left-hand key is pressed. The
personality has six left-hand
menus to choose from:
Sweep: the start, stop, and step
frequencies are set here, as well
as the number of averages to
use during the measurement.
The VIEW SPECTRM key allows
a preview of the measurement
to confirm that everything is set
up correctly. The MEASURE key
starts the actual measurement.
A HELP key is available.
Config: this menu is used to
enter the parameters which
define the hardware setup, such
as mixing numbers and LO
frequency, and the modulation
type and frequency.
Options: this menu allows you
to choose whether to turn the
following functions on or off:
single shot, FFT zoom, phase
and amplitude traces, and
invert phase mode. Also choose
whether markers use highest or
local peak mode. A HELP key is
also available here.
Process: the normalization
softkeys are located here, as
well as an autoscale key. The
FIND LO key invokes a signal
identification routine, which is
used to determine the exact LO
frequency of the DUT.
Sources: set RF, LO, and
modulation source type and
addresses here.
Power: set the power levels of
the various sources used. Also
set the modulation depth (for
AM) or modulation deviation
(for FM) when using a source
with internal modulation.