Sensing photomultiplier Pulse outputs with CTR04

[YoelGee]

Hello I am trying to measure the frequency of (analog and digital) voltage pulses coming from a photomultiplier using the USB-CTR04 module and the mcculw python library. I've been messing around with the example codes provided but I keep receiving errors such as (The DAQ device does not support analog inputs). I was wondering if I could please receive any advice on how to measure the frequency change of the pulses over time as well as keep a counter of the pulses coming in from the photomultiplier. Thank you for your time!

 

Edited December 12, 2022 by YoelGee

[Jeffrey]

The USB-CTR04 cannot measure analog signals.  the inputs can only measure digital, TTL level signals.  It can measure the frequency of a TTL level pulse(s).

There are no mcculw (python for Windows) examples for the USB-CTR04, but there are some Python on Linux examples, perhaps those would be of help to you.

https://mcc.download.ni.com/#downloads/example_programs/Product_Specific_Examples/USB-CTR4or8/Linux/python3/

Included is an example for period mode.  Take the reciprocal of the period and you have the frequency.

There are also examples for pulse counting (aka Totalize mode).  You can use the various counter on the USB-CTR04 to implement both of these functions at the same time.

In case you need it, here are:

Link to the User's manual: https://www.mccdaq.com/pdfs/manuals/USB-CTR04.pdf

and Link to the python library help file: https://www.mccdaq.com/PDFs/Manuals/UL-Linux/python/index.html

and Windows UL help file (including Python support):  https://www.mccdaq.com/pdfs/manuals/Mcculw_WebHelp/ULStart.htm