BNC 645 - Manual (Page 28)

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3.9 To Set Output Termination
A fixed series output impedance of 50 ohms to the front-panel Output
connector is set in Model 645 by default. If the actual load impedance
does not match the value specified, the output amplitude and offset
levels will be incorrect. To change this setting, follow the steps below.
Front-panel Operation
1. Press the Utility button and then press the softkey under Output
Setup.
2. Make sure the Load softkey is highlighted. If not, press the softkey
to toggle. Use the numeric keypad or the knob with cursor keys to
change the value.
3. If you wish to choose high impedance, press the softkey under
Load to toggle and make sure High Z is highlighted.
4. Press DONE to finish the entry.
5. See Figure 3-9 as a sample display.
Remote Interface Operation
Use this command for output termination setting:
OUTPut:LOAD {<ohms>|INFinity|MINimum|MAXimum}
Notes
• The range for Output Termination is from 1 ohm to 10k ohms, or
Infinite. The default is 50 ohms.
• The output termination setting is stored in non-volatile memory
and it stays after power-off or a remote interface reset.
• When the output termination is set to be “high impedance”, the
units is automatically set to be Vpp if dBm is previously selected.
3.10 To Enable/Disable Voltage Autoranging
The waveform generator by default turns on autoranging at power-on
and finds optimal settings for the output amplifier and attenuators. If
autoranging is turned off, Model 645 uses the current amplifier and
attenuator settings. To enable/disable voltage autoranging, follow the
steps below.