Power Switch Sweep Output - HP 8340A Operating Manual

Model 8340A
DESCRIPTION
The POWER power switch and the SWEEP OUTPUT front-panel BNC connector arc
d e s ribe d in this Figure.
c
PANEL LAYOUT
FUNCTIONS
POWER SWITCH selects either ON, or STANDBY. Once the ac power line bas been
plugged in, power is always being app l ied to all or part of the HP 8340A:
power is applied to t he crystal oscillator's oven to maintain operating temperature and to the
RAM circuits to maintain memory data; in the ON position, power is applied lo the entire
instrument When the HP 8340A is connected to ac power for the first time, or after a
prolonged period without power, the crystal oscillator's oven requires app
minutes to reach operating temperature (the red OVEN annunciator in the ENTRY
DISPLAY will be lighted during this warm-up pe riod)
the HP 8340A to keep the oven warm; therefore, when the instrument is not in us
POWER switch to STANDBY, and do not interrupt the ac power.
When the POWER switch is changed from STANDBY to ON, the HP 8340A w ill
automatically initiate an internal circuit check, then momentarily show the HP-IB a<l<lress
in the ENTRY DISPLAY, followed by setting the instrument functions to the last
values. If this sequence· does not happen, press [INSTR PRESET] to initiate an instrument
check, as described in Figure 3-- 12. If a warning annunciator lights at power-on, re fe r to the
display Figures 3-3, 3-4, 3-5, and 3-6 for further instructions.
SWEEP OUTPUT is provided by a front panel BNC connector
BNC connector). The output voltage range for this connector is 0to+10 volts de. When t he
HP 8340A is sweeping, the SWEEP OUTPUT is 0 V de at the begi
V de at the end of the sweep, regardless of sweep width. In CW mode, the SWEEP OUTPUT
ranges from 0 Vdc at the 10 MHz minimum frequency of the HP 8340A, to 10 Vdc at the 26.5
GHz maximum frequency, with a proportional voltage for frequencies between 10 MHz -
26.5 GHz. Pressing [CW] then [MANUAL] locks the CW frequency but allows a full-range
vol t
ge output from the SWEEP OUTPUT, which is controlled hy the rotary [KNOB]
a
( u s e ful, for example, when scaling an X-Y recorder). The output impedance at this SWEEP
OUTPUT connector is nominally 1 kfl..
[]] I
<!J
STA�OBY
ON
POWER
3-13.
Figure

Power Switch Sweep Output

Scans by HB9HCA and HB9FSX
SWEEP OUTPUT
Power must always be available to
.
( and an identical rear panel
iing of the sweep and+ 10
m
Operating Information
In STANDBY,
imately 30
rox
set the
e
- entered
3-27