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Connecting to the Instrument


This tutorial is applicable to all SHFQA Instruments.

Goals and Requirements

The goal of tutorial is to demonstrate how to connect the SHFQA to a host computer and how to configure it in general, e.g. set center frequency and power ranges of input and output, using Zurich Instrument Toolkit API.


The tutorial starts with the Instrument in the default configuration (e.g., after a power cycle). For an optimal tutorial experience, please follow these preparation steps:

  • ensure that the version of the LabOne Python API, LabOne and the Firmware of the SHFQA device, zhinst (pip install zhinst) and Python (3.7 or newer) are updated and compatible,
  • make sure that the Instrument is powered on and connected by Ethernet to a local area network (LAN) where the host computer resides,
  • start LabOne and open the LabOne Graphical User Interface using the default web browser,


You may also use a USB instead of Ethernet connection. If you do so, use the port labeled "Maintenance" on the back panel rather than the port labeled "USB". The latter is not supported until future notice.


When connecting cables to the Instrument’s SMA ports, use a torque wrench specified for brass core SMA (4 in-lbs, 0.5 Nm). Using a standard SMA torque wrench (8 in-lbs) or a wrench without torque limit can break the connectors.


First we connect to the SHFQA using Python. For this we first create a session with the Zurich Instruments Toolkit and then connect to the instrument using the following code and by replacing DEVXXXXX with the id of our SHFQA instrument, e.g. DEV12001:

## Load the LabOne API and other necessary packages
from zhinst.toolkit import Session

SERVER_HOST = 'localhost'

session = Session(SERVER_HOST)              ## connect to data server
device = session.connect_device(DEVICE_ID)  ## connect to device

Defining the data server allows users to connect to the instrument in the local network when using localhost or to specify a specific address, for example when a remote connection needs to be established to the instrument. Remember that for a remote connection, Connectivity needs to be set From Everywhere.

After successfully running the above code snippet, we check whether the Data Server, instrument firmware, and zhinst versions are compatible with each other:


If it does not throw an error, we are now in the position to access the device. If it returns an error, resolve the mismatched components identified in the error message.

  1. Configure input and output of the Channel

    All parameters can be configured by using the instrument nodes (see Node Documentation), and sent to the Instrument in a single transaction by device.set_transaction(). The instrument notes can also be found in tooltips when the mouse cursor stays on control icons and in API codes on the bottom of the LabOne User Interface after parameter updates.

    The physical Channel 1 is configured as center frequency of 6 GHz, input power range of 0 dBm, output power range of -5 dBm and both input and output are enabled.

    CHANNEL_INDEX = 0 # phyiscal Channel 1
    with device.set_transaction():
        device.qachannels[CHANNEL_INDEX].centerfreq(6e9)    # in units of Hz
        device.qachannels[CHANNEL_INDEX].input.range(0)     # in units of dBm
        device.qachannels[CHANNEL_INDEX].output.range(-5)   # in units of dBm
        device.qachannels[CHANNEL_INDEX].input.on(1)        # enable input
        device.qachannels[CHANNEL_INDEX].output.on(1)       # enable output

    Figure 1: Configuration of the Channel 1 input and output