Customer Case Studies


These are just a few applications where ASCOR has turned from a difficult test situation into a success using ASCOR's VXI systems.

A Chain is Only As Strong as its Weakest Link

A company trying to measure low frequency signals produced by a human heartbeat found it difficult- if not impossible- to find these signals amid the noise. They assumed that a low frequency switch could perform the measurements because the signals were typically 100 Hz. After integrating the hardware and the software, however, the heartbeat could not be measured. It was lost in waves of overlapping frequencies.

ASCOR was asked to help quiet the noise. We quickly determined that the noise from the VXI switch module, coupled with the switching power supply, overwhelmed the heartbeat pulse so it could not be measured.

Although a low frequency switch seemed to be the logical choice to acquire the signal, we recommended a high-frequency line of switches with electromagnetic shielding, specifically a 35-MHz 120 x 1 switch tree and a 240 x 1 switch tree. Typically, these products are used with DMMs and other scanner-type applications, but the switches provided the needed shielding and allowed the customer to measure the low-power signal of the heartbeat.

This application is a good example of the axiom that a chain is only as strong as its weakest link. Or in this case, a test system is only as good as the switching interface that routes the signals from the UUT.

The switching element of the VXI system is as important as the instruments selected. For example, there is little benefit in selecting a 5 1/2 or 6 1/2- digit voltmeter, a 10-digit counter or >200- MHz digitizer if the switching interface can't provide the signal quality needed to gather the measurements from the selected equipment.