Frequently Asked Questions#
Q: How do I set a DC offset on the output of RF modules?
A. The RF Modules (QCM-RF and QRM-RF) can only output in the specified range of 2-18.5 GHz. Therefore, it is not possible to set a DC offset via the output of the RF modules.
Q: How do I calibrate the up-converting mixer in the RF modules to get rid of spurious tones at LO and sideband?
A. Please refer to the Mixer Calibration Tutorial. You should be able to reach a spurious free dynamic range of up to 55dBc or more.
Q: The I/O LEDs are stuck at red/orange from a previous experiment. How do I clear them?
A. Uploading a new sequence to all 6 sequencers of a module clears any flags. Alternatively, you can use Cluster.clear_sequencer_flags(slot:x, sequencer:y) to clear the flags from certain module/sequencer or do a Cluster.reset() to reset all the flags in the cluster.
Q: Which version of the firmware should I use for the cluster?
A. We highly recommend using the latest released firmware version along with compatible versions of the software packages. Please refer to the compatibility matrix [here](add qblox-scheduler link).
Q: How can I get system logs from the cluster or its modules?
A. You can retrieve logs from the CMM or a specific module slot:
Item |
Command |
|---|---|
For the CMM: |
|
For a specific module: |
|
Note that in addition to app-log, you can also retrieve cfg-log and sys-log.
Q: Can I use a baseband module as a DC source?
A. Yes, you can use waveform parameterization and set the AWG offset to have the baseband modules function as a DC sources (without consuming any waveform memory!!). Notice that a program with only stop inside should be applied in the sequence.
Q: What is the power output range of a QCM-RF module?
A. The maximum output power (into 50 Ohm) for QCM-RF I is +5dBm, and for QCM-RF II is +10 dBm (< 8 GHz) and +5 dBm (> 8 GHz). The rest of the product specifications can be found in the [product datasheet](INSERT LINK HERE).
Q: Is it possible to ramp the offset voltage on the QCMs?
A. Yes, it is possible to ramp the offset voltage rather than setting it to a new value directly. This can be configured as shown in the example below:
flux_settable: callable = cluster.module.out0_offset
flux_settable.inter_delay = 100e-9 # Delay time in seconds between consecutive set operations.
flux_settable.step = 0.3e-3 # Stepsize in V that this Parameter uses during set operation.
flux_settable() # Get before setting to avoid jumps.
flux_settable(x) # Ramps the voltage to the new value: x.