HP 8340b Operating Instructions

[STOP FREQ] (HP-IB: FB) selects the stop frequency for start/stop swept operation. Press [STOP
FREQ]; then use either the rotary [KNOB], the [STEP] keys, or the numerical keys with a terminator
key to set the desired value. The restrictions that apply to [START FREQ] also apply to [STOP FREQ].
The stop frequency appears in the right FREQUENCY MHz display.
[SHIFT] [STOP FREQ] (HP-IB: SHFB) offsets the frequency displays by a fixed amount ranging from
—500 GHz to +500 GHz. This is used, for example, when the RF output of the HP 8340B/41B is
connected to a mixer, and for convenience the sum or difference frequency is shown in the displays.
Press [SHIFT] [STOP FREQ], then enter the desired offset value (—500 GHz to +500 GHz) followed
by any terminator key. The offset effects all frequency values (start, stop CF, CW, and markers), but
the offset cancels in difference functions such as [AF], [A MRK] and the dB/GHz [SLOPE] function.
The offset value is not stored in the SAVE/RECALL registers, but the current offset value does change
the values of a recalled register. Cancel the offset by pressing [INSTR PRESET], or by entering an
offset value of 0.
[CF] (HP-IB: CF) selects the center frequency for center frequency/delta frequency swept opera¬
tion. Press [CF]; then use either the rotary [KNOB], the [STEP] keys, or the numerical keys with a
terminator key to set the desired value. The order in which CF/AF are entered is not important. Start/
stop and CF/AF modes can be interchanged without changing the actual sweep limits, as described in
the [START FREQ] paragraph. The CF value appears in the left FREQUENCY MHz display.
[SHIFT] [CF] (HP-IB: SHCF) selects the incremental step size for the STEP keys (the FREQ STEP
function). The step size can be as small as 1 Hz, or as large as 10 GHz. Press [SHIFT] [CF], then use
either the numerical keys with a terminator key, the rotary [KNOB], or the [STEP] keys (which step in a
1-2-5 sequence at this time) to set the desired increment. After setting the step size, “FIXD” appears
in the right corner of the ENTRY DISPLAY. An alternative procedure couples the FREQ STEP incre¬
ment size to the AF frequency span: Press [SHIFT] [CF] [AUTO] (causing “AUTO” to appear in the
ENTRY DISPLAY) and the increment size will become 1/10 of the frequency span. AUTO is the default
condition after an [INSTR PRESET]. The step size established by the FREQ STEP function is the
same for start/stop frequencies, CF/AF frequencies, the markers, and manual sweeps. The [STEP]
keys are explained in Figure 3-8.
[AF] (HP-IB: DF) selects the delta frequency (frequency span) for center frequency/delta frequency
swept operation. Press [AF] then use either the [STEP] keys, the numerical keys with a terminator
key, or the rotary [KNOB] to set the desired value. The HP 8340B/41B will sweep from Vz AF below to
V 2 AF above the center frequency. The restrictions that apply to [CF] also apply to [AF]. The right
FREQUENCY MHz displays shows the [AF] value.
[SHIFT] [AF] has no effect on the HP 8340B/41B.
[CW] (HP-IB: CW) selects a synthesized CW frequency. Press [CW]; then use either the rotary
[KNOB], the [STEP] keys, or the numerical keys with a terminator key to set the desired value. The
right side of the ENTRY DISPLAY shows either “AUTO” if the [STEP] keys and [KNOB] are coupled
to the AF frequency span, or “FIXD” if they are not coupled (see the [SHIFT] [CF] and [SHIFT- [CW]
paragraphs for an explanation). The left FREQUENCY MHz display shows the CW value.
[SHIFT] [CW] (HP-IB: SHCW) sets the sensitivity of the rotary [KNOB] (the CW RES function) for
adjusting the CW value. Press [CW] to enter CW mode, and set the desired CW value as described in
the preceding paragraph. Then, press [SHIFT] [CW] and observe the flashing cursor in the ENTRY
DISPLAY, which identifies the digit presently affected by the rotary [KNOB], Reposition the cursor by
pressing either the left-arrow or right-arrow [STEP] key (the arrows are printed in blue above the
[STEP] keys). When the cursor is positioned over the desired digit, press [CW] to return to CW mode.
After changing the CW RES, “FIXD” appears in the right corner of the ENTRY DISPLAY. However, the
CW RES can be coupled to theAF frequency span (“AUTO” in the ENTRY DISPLAY) by pressing
[SHIFT] [CW] [AUTO], which causes the CW RES to be 1/1000 of the frequency span, reduced to the
Figure 3-7. Function Keys (2 of 3)
3-20
Operating Information
HP 8340B/41B

HP 8340b Specifications

General

Brand	HP
Model	8340b
Category	Inverter
Language	English