HP 8340A Operating Manual page 139

Model 8340A
SNdt Sweep Number, is used to establish the number of steps for a stepped sweep. The
minimum number of steps is 10, while the maximum number is 1000; the frequency sweep
span is divided by this SN number to determine the step increment. SN initializes the
stepped sweep conditions, but the IF code or the HP-IB statement TRIGGER must be used
in conjunction with SN to actually initiate each frequency step. A BASIC example:
100
OUTPUT 719; "FA8GZ FB12GZ SN400"
110 FOR N
120 OUTPUT 719; "IF"
130
NEXT N
This program causes a sweep that starts at 8 GHz and makes 400 steps (10 MHz
increments) to the 12 GHz stop frequency. The IF code in line 120 initiates each of the
400 increments; alternatively, line 120 could be:
120 TRIGGER 719
SPdt Set Power step size, is identical to the SHPL code, and both are equivalent to the
[SHIFT] [POWER LEVEL]
The power step size can be as small as 0.05 dB, or as large as 50.00 dB. Once set, the
power level can be incremented by the UP code or decremented by the DN code. Here
is a BASIC example of a 120 dB, discrete power sweep at a 12 GHz CW frequency:
100 OUTPUT 719; "CW 12 GZ"
110 OUTPUT 719; "SP 0.05 DB"
120
OUTPUT 719; "PL -110 DB"
130
FOR N
140
OUTPUT 719; "UP"
150
NEXT N
160 GOTO 120
The power sweep starts at -110 dBm, and increments in 2400 discrete, 0.05 dB steps to
an end value of 10 dBm.
SWm SWap network analyzer channels, is used in conjunction with alternate mode and
causes the foreground and background instrument states to be transposed.
Foreground refers to the present operating configuration of the HP 8340A as seen on
the front panel displays and indicators, while background is the configuration that is
derived from one of the SA VE/RECALL registers 1-9. When the HP 8340A is
alternating between the foreground and background configurations only the fore­
ground configuration shows on the front panel displays and indicators, even when the
instrument is operating under background conditions. Hence, only the foreground
configuration can be changed. SW transposes foreground and background, causing the
background to show on the front panel where changes can be made.
Define the foreground configuration as state
state "B" at the moment that alternating operation begins:
SWO causes state "A" to be the front panel state, while SWl causes state "B" to be the
front panel state.
1 TO 400
=
key which is described in Figure 3-7.
1 TO 2400
=
Scans by HB9HCA and HB9FSX
"A," and the background configuration as
At any time thereafter,
Operating Information
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