FAQs from Rohde & Schwarz

HMC804x - Data Logging Function


What is the highest sampling rate i can achieve using the log function of the HMC804x?

Can I also log data directly to a PC?


1.) Logging to internal (max. 512kB) or external memory (e.g. USB-Stick, limitted to the drive size)

This is the most easy way to read out measurement data from the unit.

It only requires a USB stick connected tot he front panel and the follwing settings in the logging menu:

  • Press [MEAS]
  • Press (LOGGING)
  • Perform the following settings to log with the highest sample rate for U/I measurement on CH1) using the softkeys and the rotating knob / :
HMC804x - Data Logging Function
  • You just have to activate the measurement and logging begins automatically
  • The interval section offers rates from 1sa/3600s up to 1000sa/s. It is set to 1sa/s for default.
  • Because the unit is locked while logging with higher acquisition rates, you have to deactivate this function to perform other settings.

After logging is switched off, the USB stick can be connected to a computer. This is an example oft he CSV files produced while logging:

HMC804x - Data Logging Function

As always reconnecting the stick is not a very practical way of handling, the remote control option should be used to transfer the file to your PC. The Data:Data? SCPI-Command will help you transferring. Formatting and saving it to a local file has to be done separately e.g. using R&S Forum Python interpreter. Please also find a script showing the principle of this operation in the advanced forum script examples at the Forum home page.

2.) Continuous measurement using remote control

This mode will provide measurement data with a rate of less than 80 sa/s. Please remember, that the ADC sampling rate is only 10Hz!

You can use the Python sample (written with the R&S Forum Python interpreter, that is available at no cost on our website) in the attachment of this article for your own experiments.

This is a sample of the acquisition rate including taking care to avoid overlapping execution / blocking due to command overflow. It also shows the response times:

HMC804x - Data Logging Function