HP 8642A Operating Manual page 219

Model 8642A/B
Appendix A
Appendix A: GLOSSARY
absolute units
In the 8642A/B, absolute units are units that can be set directly without using the relative
amplitude mode. These include dBm, V, mV, uV, EMF V, EMF mV, and EMF uV.
active function
When a function is active, you do not need to select the function's key before changing its value
with either the Knob, or Step or Data keys, or the Off/On key. A function is usually indicated
as active when the cursor in the display is above that function's value.
For example, if the cursor is over the RF frequency value, you can enter a new frequency value
or use the Knob or Step keys to change the value. You do not need to press the I FREQ 1 key
each time a change is desired.
active function prefix
Many HP-IB codes should not be entered without being prefixed by an active function code. For
a list of the active function codes and the codes that should be prefixed with an active function
code, refer to Table 3-8, Signal Generator Function to HP-IB Code (page 3-32), or Table 3-9,
Signal Generator HP-IB Code to Function (page 3-3 3).
alphanumeric
The 8642A/B has an alphanumeric display; that is, the display can show both alphabetic and
numeric characters.
ASCII
ASCII is an abreviation for American Standard Code for Information Interchange (pronounced
"ask-ee").
cursor
The cursor is the triangular segment above an alphanumeric character in the display. The cursor
usually designates the active function and the resolution of the Knob. Cursors also indicate the
status of Knob Hold and Knob Increment. Refer to Knob, page 3 - 1 4 1 .
divide bands
Divide bands are created when the Signal Generator's frequency range of 528.7 50001 to 1057.5
is divided down to create its wide RF frequency range. Refer R F Frequency, page 3-39.
function
A function refers to each capability of the 8642A/B.
Key functions are labeled directly on the key that accessed the function; frequency ( 1 FREQ 1 )
and amplitude ( [ AMPTD I ) are both key functions.
Shift key functions are labeled in blue above the key that accesses the function (for example,
REF SET and REL ZERO). You can access a shift key function by first pressing the blue
[ SHIFT I key (which causes the display to show "SHIFT") and then the key under the blue label.
(HP-IB: each shift key function has an individual HP-IB code and should not be preceded by a
shift code.)
Special functions can be selected by pressing SPCL ( [ SHIFT I f"
1
"! ), and then by keying in the
code number of the desired special function. Refer to Special Functions, page 3-168.
3-199