Controls And Readout - Hameg Instruments Hm5012-2 Handbuch

Controls and readout

Controls and readout
(1) POWER – Pushbutton and symbols for ON (I) and OFF (O)
Depressing the POWER pushbutton into the ON position
activates the display of the HAMEG logo after a few seconds,
followed by the firmware version. At this time the intensity
is set to a default value and cannot be changed.
After the firmware version goes off, the baseline (noise)
becomes visible at the graticule bottom and some
instrument setting parameters appear at the top.
2 1 3 4
1 G H z S P EC TR U M A N A LY ZE R H M 5 01 4-
POWER
7 8 9
I NT E NS
4 5 6
1 2 3
F O C U S
.
-
0 /C
TR
(2) INTENS – Pushbutton with double function and associated
LED
Briefly 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 (3) correction.
Therefore the intensity should not be set higher than
required by ambient conditions.
(3) FOCUS – TR - Pushbutton with two functions and
associated LED.
3.1 FOCUS
This function is activated by briefly depressing the
pushbutton so that the LED is lit. Then the TUNING (9)
knob can be used for focusing.
The beam diameter increases with higher intensity
settings which may cause a reduced focus. The focus
also depends on the beam deflection. 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.
3.2 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 TUNING (9) knob, 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 field. Slight pincushion
distortion is unavoidable and cannot be corrected.
34
6
8
5 7
9
2
CENTER FREQ. T U N I N G
MHz
M A R K E R
MHz
.
REF - LEVEL
dBm
.
TG - LEVEL
dBm
0 1 5 M H z - 10 5 0 M H z .
After use, the TR function can be switched off by briefly
depressing the FOCUS – TR pushbutton or any other
pushbutton (with associated LED) in the upper half of the
front panel.
(4) Numerical Pad
Within this sector are pushbuttons numbered 0 to 9, a decimal
point pushbutton and a correction pushbutton („-/C").
The following functions can be input with cipher entry or
alternately by the TUNING (9) knob: CENTER FREQ. (5)
(freq. = frequency), REF. LEVEL (7) (ref. = reference) and in
the case of HM5014-2, the output level of the tracking
generator (TG-LEVEL).
The MARKER (6) frequency can only be set by the TUNING
(9) knob. When the MARKER (6) LED is lit, using the
numerical pad (4) causes the acoustic error tone.
Before entering a cipher the wanted function must be
active, e.g. the REF. LEVEL LED must be lit if a new
reference level is to be input. Then the reference level
can be input unsigned or with negative sign. As soon as
the first value or the negative sign has been input, two
additional lines are displayed by the readout. They are
located on the left underneath the previous information.
The first line shows the actual function (e.g. CENTER:MHz)
and underneath the first keyboard input.
After input completion, the new value is accepted , (if the
value meets the specification and range limits) by briefly
depressing the active function pushbutton once again;
otherwise „Range?" is displayed.
Input errors can be corrected by briefly depressing the „-
/C" pushbutton, followed by a new input.
Pressing and holding the „-/C" pushbutton deletes the
complete keyboard entry and the readout function display.
(5) CENTER FREQ. – Pushbutton with associated LED
Briefly depressing this pushbutton switches the CENTER
FREQ. (frequency) LED on. A new center frequency can
then be set with the TUNING (9) knob or via a numerical
pad (4) entry. The center frequency is displayed by the
readout (e.g. „C:054.968MHz").
After the center frequency has been changed by
numerical pad (4) input, it must be confirmed by pressing
the CENTER FREQ. pushbutton.
The center frequency spectrum is displayed at the center
of the horizontal axis.
(6) MARKER - Pushbutton with associated LED
The MARKER is switched on by briefly 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. „M086.749MHz") 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
TUNING (9) knob.
Subject to change without notice