The National Instruments PCI-4472 and PXI-4472 are 8-channel dynamic signal acquisition devices for making high-accuracy audio-frequency measurements. The PCI-4474 is a similar 4-channel board. The vibration-optimized NI PXI-4472B offers a

信号发生器，带扫频，带频率的切换！最小可以0.1HZ。-Frequency sweep signal generator, belt, belt frequency switch! Minimum to 0.1 HZ.