Controls And Readout - Rohde & Schwarz Hameg Instruments HM5014-2 Manuel

Controls and readout

POWER
Pushbutton and symbols for ON (I) and OFF ( )
Depressing the POWER pushbutton into the ON position activates the
display of the HAMEG logo after a few seconds, followed by the fi rmware
version. At this time the intensity is set to a default value and cannot
be changed. After the fi rmware version goes off, the baseline (noise)
becomes visible at the graticule bottom and some instrument setting
parameters appear at the top.
INTENS
Pushbutton with double function and associated LED.
Briefl y depressing this pushbutton switches the INTENS LED on and
activates the TUNING knob as an intensity control. Turning this knob
clockwise increases the intensity and vice versa.
It must be noted that a higher intensity increases the beam diameter
and reduces the sharpness. This mainly occurs at the graticule border
lines and can be minimized to some degree by FOCUS
Therefore the intensity should not be set higher than required by am-
bient conditions.
FOCUS / TR
Pushbutton with two functions and associated LED.
FOCUS
This function is activated by briefl y depressing the pushbutton so that
the LED is lit. Then the TUNING
The beam diameter increases with higher intensity settings which may
cause a reduced focus. The focus also depends on the beam defl ection.
If the focus optimum is set for the screen center, it decreases with
increasing distance from the center. The function is cancelled and the
LED unlit if another function pushbutton (2, 5, 6, 7 or 8) is called.
TR
Pressing and holding the pushbutton switches off the spectrum and
parameter display and the FOCUS LED. A rectangle with horizontal and
vertical center lines is then displayed. It should be tilted using the knob
TUNING , so that the horizontal center line is parallel to the graticule
line. This adjustment depends on the orientation of the instrument to
the Earth's magnetic fi eld. Slight pincushion distortion is unavoidable
and cannot be corrected.
After use, the TR-function can be switched off by briefl y depressing the
FOCUS/TR-pushbutton or any other pushbutton (with associated LED)
in the upper half of the front panel.
Keyboard
The keyboard contains 10 decimal keys, a decimal point key and –/C key.
The following functions are available: CENTER FREQ
, TG.-LEVEL . Alternatively, these may also be adjusted with the
knob TUNING . The MARKER
knob TUNING .
The available function have to be active, before entering a value. E.g. the
REF.-LEVEL-LED have to be lit if a new reference level can be entered.
Then the reference level is able to be entered unsigned or with negative
sign. As soon as the fi rst value or the negative sign has been input, two
correction.
knob can be used for focusing.
, REF.-LEVEL
frequency can only be set by the
C o n t r o l s a n d r e a d o u t
additional lines are displayed by the readout. They are located on the left
below the previous information. The fi rst line shows the actual function
(e.g. CENTER:MHz) and below, the fi rst keyboard entry.
After complete entry, the new value is accepted, (if the value corresponds
with the specifi cations and range limits) by pressing the active function
pushbutton once again; otherwise RANGE? will be displayed. Input
errors can be corrected by pressing the "–/C" pushbutton, followed
by a new input. Pressing and holding the "–/C" pushbutton deletes the
complete keyboard entry and the readout function display.
CENTER FREQ.
Pushbutton with associated LED
Briefl y depressing this pushbutton switches the CENTER FREQ. (fre-
quency) LED on. A new center frequency can then be set with the knob
TUNING or via keyboard
the readout (e.g. „C:054.968 MHz").
After the center frequency has been changed, it must be confi rmed by
pressing the CENTER FREQ. pushbutton. The center frequency spec-
trum is displayed at the center of the horizontal axis.
MARKER
Pushbutton with associated LED
The MARKER is switched on by briefl y depressing this pushbutton
so that the LED is lit and the MARKER symbol (x) is displayed on the
spectrum. Below the center frequency, the readout now also shows
the MARKER frequency display (e.g. M086.749 MHz) and beneath the
MARKER level display (e.g. –35.2dBm) of the signal.
The MARKER frequency and level display relates to the actual MARKER
symbol (x) position, which follows the signal when being shifted to the
right or left by the knob TUNING
The keyboard is not activ when the MARKER function is switched on.
In ZERO SPAN mode the MARKER is auto-matically set to the screen
center and cannot be altered as only one frequency is measured.
REF.-LEVEL
Pushbutton with associated LED
The function is selected by pressing the pushbutton, the LED will light
up. The value can be chosen either with the knob TUNING
entering it using the keyboard
The display will show e.g. R-34.8 dBm.
The REF.-LEVEL can be set for ease of reading, shifting a spectrum
line to a suitable graticule position. The reference level setting will
not change the input sensitivity. If the noise band is in the lowest
screen position, the REF.-LEVEL value can only be decreased but not
increased. Additionally the noise band is shifted to the screen top, so
that the dynamic range becomes smaller.
The noise band is no longer visible when the ref. level is in the lowest
position and 5 dB/div. scaling is switched on. It can be made visible
again by reducing the reference level by 40 dB (e.g. from –30 dBm to
–70 dBm).
TG-LEVEL
Pushbutton with associated LED
The tracking generator output level can be set by keyborad
entry or by using the knob TUNING
. The center frequency is displayed by
.
and pressing the pushbutton again.
. The selected level
Subject to change without notice
or by
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