INPUTS and OUTPUTS
AM IN : Accepts an external signal to AM modulate the RF
output signal. Front or rear-panel input, 50
Ω
or 600
Ω
imped-
ance, both selectable from front-panel modulation menu.
FM IN : Accepts an external signal to FM modulate the RF
output signal. Front or rear-panel input, 50
Ω
or 600
Ω
imped-
ance, both selectable from front-panel modulation menu.
|
| IN : Accepts an external TTL compatible signal to
pulse modulate the RF output signal. Front or rear-panel
input, selectable from front-panel modulation menu.
EXT ALC IN (External ALC Input): Provides for leveling
the RF output signal externally with either a detector or power
meter. Signal requirements are shown in the RF Output
specifications on page B-3.
RF OUTPUT: Provides for RF output from 50
Ω
source im-
pedance. K Connector, female. Option 9K moves the RF
Output connector to the rear panel.
10 MHz REF IN: Accepts an external 10 MHz
±
100 Hz, 0 to
+10 dBm time-base signal. Automatically disconnects the in-
ternal high-stability time-base option, if installed. 50
Ω
imped-
ance.
10 MHz REF OUT: Provides a 0.5 Vp-p, AC coupled,
10 MHz signal derived from the internal frequency standard.
50
Ω
impedance.
HORIZ OUT (Horizontal Sweep Output): Provides 0V at
beginning and +10V at end of sweep for all sweep modes,
regardless of sweep width. In CW mode, the voltage is pro-
portional to frequency between 0V at low end and +10V at
the high end of range. In CW mode, if CW RAMP is enabled,
a repetitive, 0V to +10V ramp is provided.
MARKER OUT: Provides a +5V or –5V signal at each fre-
quency marker in a sweep. Signal polarity selectable from
system menu.
PEN LIFT OUT: Provides normally-open or normally-closed
relay contacts, selectable from system menu, during band-
switch points and retrace.
RETRACE BLANK OUT: Provides a +5V or –5V signal co-
incident with sweep retrace. Signal polarity selectable from
system menu.
SEQ SYNC OUT (Sequential Sync Output): P rovi des a
+5V signal during retrace, at bandswitching points, and dur-
ing each frequency step in step sweep mode, –5V during
markers, and –10V during the selected marker.
DWELL IN: Accepts an external TTL low-level signal to
pause the sweep in both analog and step sweep modes. The
sweep resumes when the signal is removed.
V/GHz Output: Provides a reference voltage relative to the
RF output frequency (refer to the table below).
AUX I/O (Auxiliary Input/Output): Provides for most of the
front and rear panel BNC connections through a single,
25-pin, D-type connector. Supports master-slave operation
with another 681XXA sweep generator and allows for a sin-
gle-cable interface with the Model 562 Scalar Network Ana-
lyzer and other WILTRON instruments. For a pinout diagram
and descriptions, see Appendix A, Figure A-2.
SERIAL I/O (Serial Input/Output): Pr ov i de s ac ce ss to
RS-232 terminal ports to support service and calibration func-
tions.
IEEE-488 GPIB: Provides input/output connections for the
General Purpose Interface Bus (GPIB). For a pinout diagram,
see Appendix A, Figure A-3.
Model Number
V/GHz Output
68137A
1.0V/GHz
68147A
1.0V/GHz
68163A
0.5V/GHz
68169A
0.5V/GHz
Input/Output Connectors
Nomenclature
Type
Location
AM IN
BNC
Front & Rear Panel
FM IN
BNC
Front & Rear Panel
|
| IN
BNC
Front & Rear Panel
EXT ALC IN
BNC
Front & Rear Panel
RF OUTPUT
K-Connector
Standard-Front Panel
Option 9K-Rear Panel
10 MHz REF IN
BNC
Rear Panel
10 MHz REF OUT
BNC
Rear Panel
HORIZ OUT
BNC
Rear Panel
MARKER OUT
BNC
Rear Panel
PEN LIFT OUT
BNC
Rear Panel
RETRACE
BLANK OUT
BNC
Rear Panel
SEQ SYNC OUT
BNC
Rear Panel
DWELL IN
BNC
Rear Panel
V/GHz OUT
BNC
Rear Panel
AUX I/O
25-pin D-type
Rear Panel
SERIAL I/O
RJ45
Rear Panel
IEEE-488 GPIB
Type 57
Rear Panel
PERFORMANCE
SPECIFICATIONS
B-6
681XXA OM
