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47
Operator’s Manual Simple AFG Application
Berkeley Nucleonics Corporation
[email protected] | www.berkeleynucleonics.com
2955 Kerner Blvd, San Rafael, CA 94901 | 800-234-7858
Rev 1.1
Trigger In signal (blue, top) that starts a burst of sine waveform (red, bottom)
External Modulation Input Connector
The MODEL 685 instrument series has an input connector to receive an external analog signal that is
used as modulating source. When the selected Run Mode is “Modulation” and the source is “External”
the instrument will use this signal to modulate the carrier waveform.
The connector type is a SMA.
External Modulating Input Description
Connector Type
1 SMA on Rear Panel for all channels
Input Impedance
10 kOhm
Input Voltage Range
±1 V for all modulations (except FSK, PSK modulation)
FSK, PSK: 0V÷3.3V with 1.65V fixed threshold
Reference Clock Input Connector
The MODEL 685 series instrument can use an external clock source to generate the sampling clock
frequency.
This feature allows to synchronize the generator with an external clock and the frequency range is 5
MHz to 200 Mhz.
The connector type is a SMA.
Reference Clock Input Value
Connector type
1 SMA on the Rear Panel
Input impedance
50 Ohm, AC coupled
Input Frequency range
5 MHz to 200 MHz
Reference Clock Output Connector
This connector outputs the internal 10MHz (100MHz Optional) reference clock used to synthesize the
DAC sampling clock. If the clock source is set as internal the reference clock output provides a 10 MHz
(100 MHz Optional) clock signal otherwise it is disabled.
The
connector type is a SMA.