Kāhu 0.3T Desktop MRI ====================== Hardware Setup -------------- This section will guide you through the setup process for the 0.3T Kāhu configuration. .. image:: /images/KahuModule_Web_6.jpg The configuration consists of a Kāhu Spectrometer and the following components: 5W RF Amplifier ^^^^^^^^^^^^^^^ This module contains: - RF power amplifier for transmit - Transmit/Receive switch - RF preamplifier for receive - Removable quarter wave line 0.3T Drive ^^^^^^^^^^ This module contains: - 3 Gradient amplifier channels - 5 Shim amplifier channels - 1 Heater driver controlled by Temp. Control PWM 1 - 1 Fan driver controlled by Temp. Control PWM 2 0.3T Magnet ^^^^^^^^^^^ This module contains: - 0.3T Magnet - Gradient & Shim coils - Magnet Heater and PT100 Temperature Sensor - Removeable RF Probe .. note:: Please follow these steps carefully before powering up Kāhu and the Drive Modules. Step 1 - Rear cable connections ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Begin by arranging the modules as shown in the image below with the Kahu Spectrometer placed on top of the drive modules. When viewed from the back, the RF Amplifier is placed on the left and the 0.3T Drive module is placed on the right. .. image:: /images/hardware/rearcableconnections_1.jpg Place the magnet assembly to the left of the drive hardware (when viewed from the back). .. image:: /images/hardware/rearcableconnections_2.jpg Connect the Kahu i-lock and PT100 ports to the drive module as shown, fastening the I/O connector with the drive tool. **Take care to not overtighten.** .. image:: /images/hardware/rearcableconnections_3.jpg Connect the Shim control cable, note that the cable is oriented with the gold contacts on top for the connection to the Kahu spectrometer. .. image:: /images/hardware/rearcableconnections_4.jpg Connect I/O port 0 of the Kāhu Spectrometer to port O of the RF amplifier as shown. .. image:: /images/hardware/rearcableconnections_5.jpg Connect the Drive Module cable loom to the magnet. .. attention:: Take care to follow the connector markings to avoid damage! .. image:: /images/hardware/rearcableconnections_6.jpg Connect the PT100 and Heater to the Drive Module. .. image:: /images/hardware/rearcableconnections_7.jpg Connect the Gradient and Shim to the Drive Module. .. image:: /images/hardware/rearcableconnections_8.jpg Connect the 3x 24V DC power supplies and the Ethernet cable to Kāhu. Kāhu can either be connected directly to your PC or to a router. See the Software Setup section for more details. .. image:: /images/hardware/rearcableconnections_9.jpg .. image:: /images/hardware/rearcableconnections_10.jpg All the necessary Rear cable connections have now been made. .. image:: /images/hardware/rearcableconnections_11.jpg Step 2 - Front cable connections ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Begin by connecting the gradient control cables to Kāhu as shown. .. image:: /images/hardware/frontcableconnections_1.jpg Connect Kahu Rx Channel 0 and Tx Channel 0 to the RF Amplifier. .. image:: /images/hardware/frontcableconnections_2.jpg Finish with connecting the Probe to the magnet. .. image:: /images/hardware/frontcableconnections_3.jpg Following this, the Kahu Spectrometer can be powered up. .. attention:: Before powering up the Drive and RF amplifier modules, ensure that Kāhu has finished powering up by connecting to it. See the next section for details on how to connect to Kāhu. Similarly, before shutting down Kāhu, ensure Drive and RF amplifier modules are turned off. The Drive and RF amplifier module can now be powered up. .. image:: /images/KahuModule_Web_6.jpg How to retune the RF Amplifier ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The 5W RF Amplifier module can be retuned by swapping the 1/4 Wave Line module. .. image:: /images/hardware/amplifier_module.jpg Remove the 4 screws on the 1/4 Wave panel. You can find this on the underside of the Amplifier. .. image:: /images/hardware/amplifier_1.jpg .. image:: /images/hardware/amplifier_2.jpg Remove the 4 phillips screws from the 1/4 wave module and carefully pull the module out to disconnect it from the amplifier. .. image:: /images/hardware/amplifier_3.jpg .. image:: /images/hardware/amplifier_4.jpg Insert the replacement 1/4 wave module, taking care to align the notch correctly. Press to click it into place and fasten to secure. Finish by refitting the 1/4 Wave panel. .. image:: /images/hardware/amplifier_5.jpg .. image:: /images/hardware/amplifier_6.jpg Software Setup -------------- .. todo:: Cam: link to main guide instead of duplicating Installing KāhuLab ^^^^^^^^^^^^^^^^^^ 1. Insert the provided USB drive into your PC or laptop and navigate to it in your file browser. 2. Double click *KahuLab-Setup.exe* and follow the install process. 3. Once the install is complete, tick the *Run KahuLab* box and click *Finish*. **KāhuLab** is customized version of JupyterLab Desktop. When the application opens you will see the name "jupyterlab". 4. Once KāhuLab opens you will see an alert displayed at the bottom of the app that says "Python environment not found." .. figure:: /images/bundled_installer.png :align: center Installing the default python environment 5. Click "Install using the bundled installer". 6. Open your file browser and copy the *kahu-workspace.zip* file onto your PC or laptop. 7. Right click the copy of the file and select *Extract All*. 8. Return to KāhuLab. 9. Once the python environment is installed, the *Open File* and *Open Folder* buttons will be activated. 10. Close and re-open KāhuLab using the desktop shortcut or start menu. 11. Click Open Folder and navigate to where you extracted the kahu-workspace folder from the zip file. Select this folder and click *Open*. 12. The KāhuLab interface will now load. 13. Double click the file *install.ipynb* on the left and when it has loaded, click Run > Run All Cells to install matipo-python library and set up the default configuration. 14. Click “conda: jlab_server” in the top menu bar. .. figure:: /images/restart_session.png :align: center Restarting the session 15. Click the reload icon to restart the session. Connecting to Kāhu ^^^^^^^^^^^^^^^^^^ When connecting to Kāhu by direct ethernet cable from a PC, assign a manual IP with settings: Address: 192.168.137.1 Netmask: 255.255.255.0 Gateway: 192.168.137.1 Kāhu may also be connected to a router via ethernet cable. In this case check the router admin page for the automatically assigned IP address. This IP address must be set in *matipo-config.yaml* file located in the kahu-workspace folder as the device_address. After saving *matipo-config.yaml* you will need to click “conda: jlab_server” in the top menu bar then click the reload icon to restart the session. The default *matipo-config.yaml* file is created when you run install.ipynb, and contains the default Kāhu device_address: 192.168.137.2 Trouble Shooting ^^^^^^^^^^^^^^^^ If you see the error similar to the following when loading a dashboard:: Error: [Errno 2] No such file or directory: 'C:\\Users\\user\\programs/find_freq.py'; in file C:\Users\user\Documents\kahu-workspace\dashboards\Utilities.py You have not created the *matipo-config.yaml* file and need to complete steps 13-15 in the Installing JupyterLab section. System Calibration ------------------ .. |ilumr| image:: /images/ilumr_icon.png Click the |ilumr| icon on the left to open the launcher. There will be two categories: *General* and *ilumr* which may be collapsed, expanded, and repositioned. To check the connection open the System dashboard. If the connection is successful, it will load and display the magnet temperature plot. If it is unable to connect it will print a timeout error. Wait until the temperature has stabilised to 30℃ before continuing with the calibration setup. .. include:: /dashboards.rst :start-after: .. start-0.3T-setup-calibration :end-before: .. end-0.3T-setup-calibration Conclusion ---------- With calibration complete, you can proceed to run the other dashboard apps, e.g. :ref:`dashboards:2D RARE`, or notebooks. Example notebooks have been included in the `ilumr-resources/notebooks` directory of the workspace, and educational labs in the `ilumr-courseware` directory.