Stanford Research Systems DS345, Manual

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DS345 FEATURES
2-8
Timebase Input
This 1k
Ω
impedance input allows the DS345 to lock to an external timebase.
The external source should be greater than 1V pk-to-pk and should be within
±2 ppm of 10 MHz or any subharmonic down to 1.25 MHz.
The shield of
this input is connected to earth ground.
3) Auxiliary Outputs
10 MHz Output
This output produces a >1V pk-pk 10 MHz sinewave from the DS345's inter-
nal oscillator. It expects a 50
Ω
termination.
The shield of this output is
connected to earth ground.
Modulation Out
This output generates a 0 - 5V representation of the current modulation func-
tion. The shield of this output is tied to that of the function output and may be
floated up to ±40V relative to earth ground.
Trigger Output
This TTL compatible output goes high when a triggered sweep or burst be-
gins, and goes low when it ends. This may be used to synchronize an exter-
nal device to the sweep/burst. The shield of this output is tied to that of the
function output and may be floated up to ±40V relative to earth ground.
Sweep Output
This output generates a 0 - 10 V ramp that is synchronous with the DS345's
frequency sweep. The shield of this output is tied to that of the function out-
put and may be floated up to ±40V relative to earth ground.
Marker Output
This TTL compatible output goes high when the DS345's frequency sweep
passes the start marker frequency, and goes low when the sweep passes the
stop marker frequency. The shield of this output is tied to that of the function
output and may be floated up to ±40V relative to earth ground.
Blank/Lift Out
This TTL compatible output is low during the upsweep of a frequency sweep,
and is high during the sweep retrace. The shield of this output is tied to that
of the function output and may be floated up to ±40V relative to earth ground.
4) GPIB Connector
If the DS345 has the optional GPIB/RS232 interface this connector is used
for IEEE-488.1 and .2 compatible communications.
The shield of this con-
nector is connected to earth ground.
5) RS232 Connector
If the DS345 has the optional GPIB/RS232 interface this connector is used
for RS232 communication. The DS345 is a DCE and accepts 8 bits, no pari-
ty, 2 stop bits and 300 and 19.2k Baud.
The shield of this connector is
connected to earth ground.