FAQs from Rohde & Schwarz

Use of high impedance active probes


I want to use a high impedance active probe with my Advantest analyzer for my measurements on printed circuit boards. Is this possible with my analyzer?


Yes, it is possible to analyze circuit points that cannot be loaded with the

50 ohm of the analyzer input. The use of high impedance probes on spectrum

analyzers is a common task in the design of RF circuits.

The Rohde & Schwarz probe adapter RT-ZA9 allows Rohde&Schwarz active

probes from the RTO oscilloscope series to even be used on Advantest analyzers.

Basically, the RT-ZA9 provides an interface between the probe’s BNC socket and the needed

N-socket. The probe adapter RT-ZA9 also supplies the probe with the necessary

voltages via an USB connection. You will find a suitable USB port on the front panel

of the U3700 series and U3800 series. Simply connect the probe via the adapter

to the analyzer and power it up by connecting the adapter to the USB port of

the Advantest analyzer.

For operation, make sure to do the following:

- Correct the 10:1 ratio of the probes by entering a level offset of 20 dB.

- Set the RF input attenuation to an appropriate level.