Frequency Setting; Trigger Source; Special Waveforms; Staircase - Metrix GX1010 Notice De Fonctionnement

pressing the blue EDIT key followed by the FSK key. When FSK edit is selected the lamp
beside the FSK flashes to show edit mode regardless of whether FSK mode is currently
selected to be on or off.

4.6.1. Frequency Setting

The two frequencies, FREQ A and FREQ B, between which the waveform is switched are
set in exactly the same way as the frequency on the Main menu; in fact, FREQ A is the
main generator frequency in non-FSK mode and changing FREQ A on the FSK edit menu
will also change the frequency shown on the Main menu.

4.6.2. Trigger Source

With the edit cursor in the SOURCE field of the FSK edit menu, the DIGIT keys or rotary
control can be used to select EXTernal, MAN/REMOTE, or internal Trigger GENerator as
the trigger source which controls the frequency shifting.
With the source set to EXTernal the frequency is switched at each rising edge of the signal
applied to the EXT TRIG input. The minimum pulse width that can be used with the EXT
TRIG input is 50ns and the maximum repetition rate is 1MHz.
With the source set to MAN/REMOTE, the frequency is switched with each press of the
front panel MAN/SYNC key or by the appropriate command via the RS232 or GPIB
interfaces.
With the source set to TGEN, the frequency is switched at each rising edge of the internal
trigger generator; the trigger generator produces a squarewave with a period that can be
set from 0·02ms (50kHz) and 200s (·005Hz). Period entries that cannot be exactly set are
accepted and rounded up to the nearest available value, e.g. ·109ms is rounded to ·12ms.
The generator output is available as a TTL level signal at the rear panel TRIG/SWEEP
OUT socket.
Setting the frequency of the internal trigger generator is fully described in the Trigger
Source section of TRIGGERED BURST AND GATE. Because the internal trigger generator
can be used by the trigger, gate, FSK and AM functions, and can be set on their respective
edit menus, an information field is displayed in brackets beside TGEN when this is selected
on the source. This field will show [FREE] when TGEN is not used elsewhere, or any of the
letters [G, F, A, T] to indicate that the generator is currently set as the source on the GATE,
FSK, AM, or TRIG menus respectively in addition to the menu currently displayed.
4.7.

Special Waveforms

4.7.1. Staircase

Staircase, or multilevel squarewaves, are selected by pressing the STAIR key; when
STAIR is selected the lamp beside the key lights. The default staircase is a 4-level
waveform with level changes at 90° intervals; to modify or define a new staircase select the
staircase edit menu by pressing the blue EDIT key followed by STAIR. When staircase edit
is selected the lamp beside the STAIR key flashes to show edit mode; selecting edit mode
always sets staircase on and symmetry to 50% to permit visual checking of the waveform.
GX1010
FREQ A=10·00000kHz
FREQ B=10·00000MHz
SOURCE=EXT
TGEN=1·00ms 1·000kHz
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