Front Panel Connections; Fig. 7.1: Outputs On The Front Panel; Fig. 7.2: Output Signal Controlled By A Gate Signal; Usb Connector - Hameg HMF2550 Handbuch

F r o n t p a n e l c o n n e c t i o n s

7 Front panel connections

7.1 Signal Output
The signal output of the HMF2525 / HMF2550 has an impedance
of 50Ω and can be turned on or off with the key OUTPUT
output is short-circuit proof and protected against short-term
applied voltages of up to ±15 V (DC and AC peak).
7.2 Trigger Input
The HMF2525/2550 offers different operating modes. In addition
to the standard mode „free-running" (continuous), signals may
be generated triggered or gated. The selection is performed in
the BURST or SWEEP modes. After turn-on the instrument will
be in the free-running mode.
In gated mode the output signal will be gated by a TTL signal,
applied to the TRIG INPUT connector
operating mode is asynchronous. The phase of the output signal
can be any when gated because the signal will be continuously
generated. Normally, the output will be activated when the gate
signal is HIGH (TTL) , if it is LOW it will be off.
Wether the signal starts at a rising or falling edge can be slected
at the resp. „system settings" menu.

Fig. 7.1: Outputs on the front panel

In external trigger mode the trigger is also applied to the TRIG
INPUT connector . A trigger signal may be also a command
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*TRG sent via the interface. This operating mode is synchronous,
i.e. the triggered signal will start at its beginning i.e. at zero. One
or several periods will be generated depending on the number
of cycles set on the instument before.
In case the sweep function is activated, a trigger will generate
just one sweep, after completion the function generator will
wait for the next trigger. During the waiting period no signal
will be generated.

Fig. 7.2: Output signal controlled by a GATE signal

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Subject to change without notice
. The
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on the front panel. This
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7.3 Trigger output
The HMF2525/2550 can also generate a trigger signal in sweep
mode when the swept frequency reaches a preset marker fre-
quency, this trigger is available at the TRIG OUTPUT connector
7.4

USB connector

The USB connector on the front allows software updates of the
HMF2525 / HMF2550 firmware via an FAT or FAT32 formatted
USB stick as well as entering arbitrary functions in the CSV
format.

8 Rear panel connections

Fig. 8.1: Signalinputs and –outputs including
modulation input at the rear panel
8.1 Modulation input
The HMF2525 / HMF2550 allows to control the amplitude of the
output signal by an externally applied DC voltage to the MODULA-
TION INPUT connector . A voltage from 0 to +5 V will influence
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either the output amplitude (AM), the frequency deviation (FM),
the phase (PM), the hop frequency (FSK), resp. the pulse width
(PWM) between 0% and 100%, depending on the value set at the
instrument. The frequency, resp. the signal shape of the exter-
nal modulation signal has an influence to the resp. modulation
frequency and appearance.
8.2

Sweep out

The sweep sawtooth is available at the BNC connector SWEEP
OUT on the rear panel, the signal runs from 0 V (start fre-
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quency) to +5 V (stop frequency). For further information about
the SWEEP function consult the section „Extended operating
functions".
Fig. 8.2: Swept sine wave; sawtooth output
.
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