Demod (Demodulator/Audio Output); Detec (Rms Or Minmax Detector); Hold (Activate Hold Mode) - Aaronia NF-5030S Manual

7.0 The main menu

7.12 Demod (demodulator/audio output)

The demodulator allows you to audibly reproduce pulsings and modulations of
up to approx. 3.5kHz. SPECTRAN offers two modulation modes:
AM (Amplitude modulation) and FM (Frequency modulation). You can switch
between "AM" and "FM" at any time by pressing the dot key. By selecting Off
or pressing the menu key, the demodulator can be turned off.
Please note that in oposition to the usual broadband detectors, demodulation
only occurs around the center frequency! The bandwidth is adjustable using
the RBW setting. Hence, you can selectively "monitor" small frequency ranges.
However, in this mode, the filter is slightly "softer" compared to other modes, so
unwanted strong signals on neighbouring frequencies might audibly "spill" into
the currently selected frequency range.
This frequency-exact, selective "acoustic evaluation" can be helpful when iden-
tifying signal sources. As demodulation occurs in real-time, it is also perfectly
suited for locating signal sources very quickly.
7.13 Detec (RMS or MinMax detector) [Shift key]
Here you can choose between two different detectors. Possible choices are:
RMS (Default)
MinMax
This mode allows you, for instance, to find out if a certain signal is modulated:
When the displayed signal level is larger in MinMax mode than in RMS mode,
the signal must be modulated. If both modes show a nearly identical display, the
signal is unmodulated.
HINT: You can change the detector at any time by just pressing the Shift key.

7.14 Hold (activate HOLD mode)

By selecting On you can activate HOLD mode, indicated by the word "HOLD" in
the status field. Likewise, Off turns it back off.
In HOLD mode, the spectrum display does not get erased, thus all measured
signals stay visible at all times. Only signals stronger than those already recor-
ded will be able to overwrite the display.
Likewise, only the highest markers since the last activation of HOLD mode will
be displayed, including frequency and field strength/voltage. HOLD mode turns
SPECTRAN into a very sophisticated tool - it is really an "ADVANCED HOLD":
You can use this mode for creating full-day diagrams: Just leave SPECTRAN
in HOLD mode for, say, 24 hours, and the next day you will be able to check
what exactly happened in the past 24 hours. This way, you can also use
28 Firmware V 1.0 / © 2005-2013 by Aaronia AG, D-54597 Euscheid, www.aaronia.com