QtDMM

QtDMM is a great GUI interface to Digital MultiMeters that have a computer interface. It has a few bugs, but these can be worked around.

QtDMM Bugs

It is very important that you build it correctly from source. You need to turn off the FORTIFY flag checking in gcc. See Compiler Flags FORTIFY

./configure BASECFLAGS=-U_FORTIFY_SOURCE
make

Import and export of test data does not work perfectly. You can export the data, but it screws up the recorded data by saving every sample with the same date-time stamp -- and without fractions of a second which is critical since you can sample every 100 milliseconds. This is not so much of a problem since you at least know the time between samples which is good enough for graphing.

ZMeter alternative

An alternative to QtDMM is ZMeter.

To build it you need the qt3-dev libraries. Unpack the tarball. Set the QTDIR environment variable! The following is for building under Ubuntu, but other distros are probably not much different:

aptitude install qt3-dev-tools
export QTDIR=/usr/share/qt3/
./configure
make

I use a RadioShack Model #22-812. I'm not normally a fan of anything from RadioShack, but this meter is very inexpensive and it has a very useful RS-232 serial interface.