Data AcQuisition And Real-Time AnalysisScope - Spectrum - Spectrogram - Signal Generator
Software for Windows
Science with your Sound Card!
Contact us about
No Input Signal
However, on a Vista or Windows 7, 8, or 10 system the Input button may be disabled if you have no input device plugged in... connect to Mic In or Line In and restart Daqarta. See Vista / 7 / 8 / 10 Issues for this and related topics.
Otherwise, if the Input button is enabled, check that the input device name at the top of the Input control dialog is the one you intend to use. You can change the Input Device in the Start Preferences dialog if you have more than one on your system. (But note that the change won't take effect until the next Daqarta session.)
Make sure that the proper input line is selected to match your chosen input, typically Mic or Line.
Make sure that there is a signal at the chosen input, and that the connector is fully plugged in. If you are using a microphone you can provide a test signal by placing it near a sound source such as a radio, or singing or talking into it, or blowing gently across it, or even brushing it lightly with your finger or across your sleeve.
If you are using Line input, verify that there is a signal present at the source by removing the cable and plugging in headphones. (The source may be Daqarta itself via the Generator.) NOTE: The signal must be AC. Most sound cards do not respond to steady voltages, such as those from a battery. (See DC Measurements And Outputs for ways around this.)
Note: If you set the input line to SPDIF (a digital-input format not supported by standard Windows waveform-input protocols), Daqarta may not receive any data from the sound card, and may show 'TRIG WAIT' or 'SYNC WAIT' on the trace as it waits for data that never arrives.
In waveform display mode (Spectrum and Sgram/PT off), increase the display magnification (PgUp key). Keep increasing until the trace line becomes jagged or noisy-looking. The line should look "busy" even if there is no signal present, just due to noise in the sound card itself.
If you see an unchanging (although jagged) line, make sure that the display is updating properly: Check that Daqarta is unPaused, Trigger is off, and Holdoff is set to 0. Make sure Trace Update (in the X-Axis dialog) is set to minimum.
If you see a busy, noisy line but without your signal apparent, review the steps to insure you have a signal connected to the proper input of the selected device. Wiggle cables, or try replacing the cables and/or microphone with others.
Right-click the Windows Mixer (the small speaker icon in the system tray) and select Open Volume Control. Then select Options - Properties from the menu and set Mixer Device to Recording. Make sure all controls in the list are enabled and click OK. Check the resulting mixer control panel and see if the settings agree with those in the Daqarta Input dialog. In particular, look for any extra switches that might be off.
Some sound cards have custom mixers, typically with their own icons in the system tray. Look at all the controls and see if there are any likely suspects.
If you find a control that solves the problem, note that although Daqarta may not recognize it internally, it does preserve all settings for the entire sound card in the Daqarta0.MIX file, and will use them in future sessions. (Each time you exit Daqarta, all settings will be restored to the way they were before you started that session.)
See also Troubleshooting
Questions? Comments? Contact us!We respond to ALL inquiries, typically within 24 hrs.
Over 35 Years of Innovative Instrumentation
© Copyright 2007 - 2021 by Interstellar Research
All rights reserved