HP 8341b Operating Instructions

next lowest integer power of ten (for example, a frequency span of 16 GHz corresponds to a CW RES
of: 16GHz/1000=16 MHz; 16 MHz reduced to the next lowest integer power of ten equals 10 MHz,
which is the CW RES). For frequency spans less than 1000 Hz, the AUTO CW RES is 10 Hz. AUTO is
the default condition for CW RES after an [INSTR PRESET].
[POWER LEVEL] (HP-IB: PL) controls the output power level of the HP 8340B/41B, when it is
internally leveled. Press [POWER LEVEL]; then use either the rotary [KNOB], the [STEP] keys, or the
numerical keys with the [dB(m)] terminator key to set the desired value (resolution 0.05 dB). When
externally leveled, [POWER LEVEL] selects the external detector feedback voltage to which the HP
8340B/41B will attempt to level, with a range of+6 dBV (2.00 V) to —66 dBV (500 yV) and a resolution
of 0.1 dB. The EXT INPUT (BNC connector) accepts either positive or negative inputs. When in the
[SHIFT] [METER] (open-loop) mode the [POWER LEVEL] entry controls the linear modulator, as
explained in Figure 3-16. In any of these three modes, the POWER dBm display shows the output
power to the nearest 0.1 dB (see Figure 3-3 for information on this display, and its UNLEVELED
indicator). The output power can range from -110 dBm to a maximum value that depends on fre¬
quency (see Table 1-1 for power specifications). Figure 3-17 explains [PEAK], [PWR SWP], and
[SLOPE] power functions.
[SHIFT] [POWER LEVEL] (HP-IB: SHPL) selects the incremental step size for the [STEP] keys when
they are used for the power level functions ([POWER LEVEL], [PWR SWP], or [SLOPE]). This is the
LVL STEP function. Press [SHIFT] [POWER LEVEL]; then use either the rotary [KNOB], the [STEP]
keys (which step in a 1-2-5 sequence in this mode), or the numerical keys with the [dB(m)] terminator
key to set the desired step size. The step size can range from 0.05 dB to 50.00 dB. Consult Figures 3-3
and 3-17 for further information on power functions.
[SWEEP TIME] (HP-IB: ST) selects the sweep times for frequency sweeps or power sweeps (power
sweep is explained in Figure 3-17). Press [SWEEP TIME]; then use either the [STEP] keys (which
increment in a 1-2-5 sequence for sweep time), the rotary [KNOB], or the numeric keys with the [sec]
or [msec] terminator key to set the desired value. Sweep time has an allowable range of 10 msec to
200 seconds, but the fastest sweep time is constrained by the frequency span: The sweep rate
cannot exceed 600 MHz/msec (300 MHz/msecfor HP 8341B Option 003) (for example, the full 26.49
GHz frequency span of the HP 8340B can be swept no faster than 26490/600=44.15 msec). The
fastest possible sweep can be determined automatically: Press [SWEEP TIME] [AUTO] to obtain
the fastest possible calibrated sweep time for any sweep span. The right-hand corner of the ENTRY
DISPLAY shows “AUTO” when the sweep time is coupled to the frequency span, or “FIXD” when
sweep time is independent. AUTO is the default condition after [INSTR PRESET]. Also see TL in the
HP-IB section.
[SHIFT] [SWEEP TIME](HP-IB: SHST) places the HP 8340B/41B into CF/AF sweep mode, with AF
controlled only by the [STEP] keys and CF controlled by either the rotary [KNOB] or the numerical
keys (with a terminator key). This is the ZOOM function, which allows the operator to quickly zoom-in
on a frequency band of interest even from very wide sweeps.
[SHIFT] (HP-IB: SH) activates functions that are printed in blue on the front panel, as well as special
functions. All [SHIFT] functions are described in this Operation chapter, and are summarized on the
two information cards located below the HP 8340B/41B.
Figure 3-7. Function Keys (3 of 3)
HP 8340B/41B
Operating Information
3-21

HP 8341b Specifications

General

Brand	HP
Model	8341b
Category	Inverter
Language	English