Hi everyone,
I have a cDAQ-9171 with a NI-9232. To the first Channel is a microphone over a BNC coaxial cable connected. The DAQ is connected to my PC over USB. I use Linux and Python to speak to the device.
Everything is running fine, besides that the signal has a very stand out noise which is constant over every setting I am choosing.
I use
task.ai_channels.add_ai_microphone_chan(f'{device_name}/{channel}', mic_sensitivity=mic_sens, max_snd_press_level=max_snd_press_level, current_excit_val=0.004)
# Parameters for recording
samples_per_channel = 10000
sample_rate = 51200
duration = 10
device_name = 'cDAQ1Mod1'
channel = 'ai0'
max_snd_press_level = 100
mic_sens = 1000
but it doesn't matter what kind of setting I choose, the noise is constant and I don't get why it is so much in the foreground.
I used the microphone on another device (which only cost me 300 Euro) and got a better signal with a better Signal-to-noise ratio in comparison to this DAQ. I also grounded the chassis. But the signal stays the same.
Switched also the coaxial cable, but still no improvement. Are there any settings to adjust for the amplifier? It feels like this amplifier is oversteered.
Does someone has an idea what I do wrong or is this a known problem of the DAQs from NI with microphones?
Thanks for any feedback
