Digital Multimeters - Tenma 72-7735

The PC Inteface
           With this multimeter comes a PC interface that is Infarared on one side and RS232 serial on the other. The IR side plugs into the DMM as you can see in the pictures below. It stays in the socket quite snugly so you don't have to worry about it popping out. The other side connects to an RS232 serial port, if you have one.


           While I applaud this DMM for having a PC interface, the fact that it is RS232 serial is a little demoralizing. I know that many people do not have experience with this type of connector which means difficulty and struggle for some people. However, I'll do my best to show the steps to get it working.

Setting Up Your Computer
           To use the cool PC interface feature of the Tenma 72-7735 DMM, you need to have the cd-rom so that you can install their software. Navigating the cd-rom was a little annoying to me at first glance because they had 10-12 different installers for their different multimeters. But, find the 72-7735 in the long list and install it on your computer.


           At this point you can follow the 72-7735 PDF file on the CD-ROM to try and get things connected, or just do what I did. The users manual lists the communication type. So you'll need to adjust your serial port in your operating system to match their specifications (see the pictures above). After you've got everything setup, give your operating system a reboot and test out the PC interface.

Using Tenma's Software
           If you set everything up correctly, the software runs pretty smoothly and the DMM is recognized almost immediately once you press the connect button. At this point you can configure Tenma's software to plot and log data over time, along with many other very nice features for such a low cost DMM.


           The photos and video seen above show you the accuracy and response time that you can expect from the DMM to PC interface. While the software might not be as professional as matlab or labview, for a hobyyist it offers some great features that are very useful for taking measurements and data logging.