QA401 Quick Start
Download and install the latest QA401 software
| During install, make sure the "Run InstallDrivers.exe" box is checked |
|
| After installation is complete, click on the new QA401 link on your desktop |  |
| When the application launches, notice that you can scroll the control region by clicking and holding the click in an empty area and dragging with your mouse or finger |  |
| Plug in the QA400 hardware. You should see the hardware get configured, followed by a connected message. | |
| Scroll down to the run/stop button and press it. You should see spectrum data updating in yellow. |  |
| Disable the attenuator. When you click the ATTEN button, you should see the button turn off and hear a relay click inside the QA401. The front-panel LED marked ATTEN will also extinguish. | |
| Short the 2 left BNC inputs using 0, 50 ohm or 75 ohm BNC shorting blocks (not included). |  |
| In the application, press the PWR button. This will enable reporting of measured power in the indicated bandwidth. Confirm this is around –120 dBFS |  |
| Leave the L- shorting block applied, and using a BNC cable (not included) connect the Left + Output to the Left + Input |  |
| Hold the control key while clicking on the GEN1 button. This will bring up the GEN1 context menu. Change the amplitude to –16 dBFS. This is the sweet spot for the THD measurements on the QA401. |  |
| Select OK, and then click on the GEN1 button to enable the generator. | |
| Press the THD button. Increase the FFT depth to 32K. To change a knob setting, click on the knob and drag up or down until you see the value you desire appear in the on-screen indication. A small “LED” will light on the knob to indicate it can be dragged. |  |
| With the output connected to the input, this is called “loopback” mode. You should see see a THD figure of around –110 dBFS. |  |
|
Congratulations! You’ve made your first measurements! If you run into any problems, just contact us at the SUPPORT alias. There is also a help file installed with your QA401 application. Just press “F1” while running the application to launch the PDF, or select Help-> Launch Help. |
