Hameg HM5014-2 Manual page 31

VBW
Pushbutton with associated 4-kHz-LED
Pressing this pushbutton switches the video fi lter on or off. In ON-
condition the video fi lter reduces noise using a low pass fi lter. Weak
signals, which normally get lost in the noise, may become visible when
activating this function.
Note:
If the video fi lter is activated and the SPAN is too high, "uncal"
is displayed by the readout, as the signal level(s) do not reach
their real height on the screen.
In case of measuring pulses, the video fi lter should not be used.
AVERAGE
Pushbutton with associated LED
Pressing this pushbutton switches this function and the associated LED
on or off. In Average mode, the spectrum recordings are continuously
calculated and displayed as arithmetic mean value. Some functions
cannot be called in AVERAGE mode and cause only an acoustic error
message.
When the AVERAGE LED lit, briefl y depressing the pushbutton swit-
ches LED and function off and erases the previous calculation result.
AVERAGE also activates the Max. HLD
the result) to avoid waiting time and enable direct switch over from
AVERAGE to Max. HLD (maximum hold).
Max. HLD
Pushbutton with associated LED
Pressing this pushbutton switches the Max. HLD (maximum hold)
function and the associated LED on or off. Max.HLD stores and dis-
plays the maximum level values of the spectrum; values below the
maximum get lost. In case of pulsating RF-signals the signal reading
should not be made until the maximum signal height is present. Some
functions cannot be called in Max. HLD mode and cause an acoustic
error signal.
When Max. HLD is activated and the associated LED lit, briefl y depres-
sing the pushbutton switches LED and function off and erases the Max.
HLD values. Max. HLD also activates the AVERAGE
displaying the result) to avoid waiting time and enable direct switch over
from Max. HLD to AVERAGE mode.
LOCAL/PRINT
Pushbutton with two functions and associated LED.
LOCAL function
Remote mode can be switched on or off via the built in serial interface. In
remote condition the RM LED is lit and with the exception of the LOCAL/
PRINT pushbutton all other controls are deactivated. Briefl y depressing
the LOCAL/PRINT pushbutton switches over from remote (RM) to LOCAL
operation, so that all controls become operative again.
PRINT function
On condition that the RM-LED is not lit (LOCAL mode), documentation via
a PC printer can be started if the following conditions are required:
st
1 The serial interface of the spectrum analyzer must be connected
with a serial PC (COM) port.
nd
2 The provided PC software must be activated and the software COM
port setting must comply with the hardware connection.
function (without displaying
function (without
C o n t r o l s a n d r e a d o u t
B
Pushbutton
The spectrum analyzer contains a second signal and parameter
memory that is called "B". This memory is volatile and switching the
instrument off will lose its content. Memory "B" can only be activated
with the instrument on, after a spectrum has been previously stored
by A→B-function; otherwise an acoustic error message is audible.
Briefl y depressing the B pushbutton switches over to B display which
is indicated by the readout (top left position) on the right of the center
frequency display.
A – B
Pushbutton
This function can be called only if a spectrum has previously been
stored in memory B. Then the result of the actual recorded spectrum
minus the content of memory B is displayed. On the right on the center
frequency the readout shows A - B.
The A–B-function eases the perceptibility of changes in signal level,
frequency and shape when adjustments are made (if the previous
setting had been stored in memory B). When switching the A–B-func-
tion on, the reference level is automatically changed for better reading.
A manual correction overrides the automatic setting.
A
Pushbutton
The spectrum analyzer contains 2 memories named A and B. The
memory A content is the actual signal at the spectrum analyzer input
that is continuously refreshed. When the A pushbutton is pressed, only
the actual spectrum is written into the memory, read and displayed.
The letter A indicates this state after the CENTER FREQUENCY in-
formation in the readout.
RECALL/SET
Pushbutton with double function
Note: The RECALL function cannot be activated as long as AVERAGE
or Max. HLD is present.
RECALL: The instrument has a memory for 10 instrument parameter
settings that can be called by this function.
Pressing the RECALL pushbutton calls the function so that e.g.
"Recall9" is displayed by the readout where the SPAN was previously
indicated. As long as "Recall ..." is displayed (approx. 2 seconds) the
RECALL and SAVE pushbuttons can be used to select the memory
location with ciphers between 0 and 9. Each time the memory loca-
tion setting is changed by pressing the SAVE or RECALL pushbutton,
the (approx.) 2 seconds for the memory location display time starts
again.
SET (push long): Calling an instrument setting fi rst requires that the
memory location be displayed, which is called by briefl y pressing the
pushbutton. Pressing and holding the pushbutton while the memory
location is displayed, causes the instrument to accept the settings
from the selected memory location to the front panel. The take over is
acknowledged by a double beep.
Function break off: After approx. 3 seconds waiting time the RECALL
function is left automatically if it has been called inadvertently or not
used.
The Recall memory location display is then switched off.
31
Subject to change without notice