HP Signal generator HP8657B

Note:

• This instrument does not support reading back values, as it is a listen-only GPIB device.

• Other instruments of this family could be implemented using the dynamic ranges feature.

• Optional pulse modulation feature is not supported yet.

Glossary:

Abbreviation	Explanation
AM	Amplitude Modulation
FM	Frequency Modulation
dBm	power level in dB referenced to 1mW

class pymeasure.instruments.hp.HP8657B(adapter, name='Hewlett-Packard HP8657B', **kwargs)

Bases: Instrument

Represents the Hewlett Packard 8657B signal generator and provides a high-level interface for interacting with the instrument.

class Modulation(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)

Bases: IntEnum

IntEnum for the different modulation sources

property am_depth

Set the modulation depth for AM, usable range 0-99.9%

property am_source

Set the source for the AM function with Modulation enumeration.

Value	Meaning
OFF	no modulation active
INT_400HZ	internal 400 Hz modulation source
INT_1000HZ	internal 1000 Hz modulation source
EXTERNAL	External source, AC coupling

Note:

• AM & FM can be active at the same time

• only one internal source can be active at the time

• use “OFF” to deactivate AM

usage example:

sig_gen = HP8657B("GPIB::7")
...
sig_gen.am_source = sig_gen.Modulation.INT_400HZ    #  Enable int. 400 Hz source for AM
sig_gen.am_depth = 50                               #  Set AM modulation depth to 50%
...
sig_gen.am_source = sig_gen.Modulation.OFF          #  Turn AM off

check_errors()

Method to read the error status register as the 8657B does not support any readout of values, this will return 0 and log a warning

clear()

Reset the instrument to power-on default settings

property fm_deviation

Set the peak deviation in kHz for the FM function, useable range 0.1 - 400 kHz

NOTE:

the maximum usable deviation is depending on the output frequency, refer to the instrument documentation for further detail.

property fm_source

Set the source for the FM function with Modulation enumeration.

Value	Meaning
OFF	no modulation active
INT_400HZ	internal 400 Hz modulation source
INT_1000HZ	internal 1000 Hz modulation source
EXTERNAL	External source, AC coupling
DC_FM	External source, DC coupling (FM only)

Note:

• AM & FM can be active at the same time

• only one internal source can be active at the time

• use “OFF” to deactivate FM

• refer to the documentation rearding details on use of DC FM mode

usage example:

sig_gen = HP8657B("GPIB::7")
...
sig_gen.fm_source = sig_gen.Modulation.EXTERNAL     #  Enable external source for FM
sig_gen.fm_deviation = 15                           #  Set FM peak deviation to 15 kHz
...
sig_gen.fm_source = sig_gen.Modulation.OFF          #  Turn FM off

property frequency

Set the output frequency of the instrument in Hz.

For the 8567B the valid range is 100 kHz to 2060 MHz.

id = 'HP,8657B,N/A,N/A'

Manual ID entry

property level

Set the output level in dBm.

For the 8657B the range is -143.5 to +17 dBm/

property level_offset

Set the output offset in dB, usable range -199 to +199 dB.

property output_enabled

Control whether the output is enabled.

reset()

Resets the instrument.

shutdown()

Brings the instrument to a safe and stable state