A compact ECR-type plasma device with radial trapping only was built in the Atomki ECR Laboratory called Table Plasma Generator (TPG). The relatively big plasma chamber makes it an ideal device to install Langmuir-probes into it easily while the plasma is still observable with eyes or by cameras. Four cylindrical Langmuir-probes parallel to the plasma chamber axis are installed to the rotatable endplate of the TPG's plasma chamber. This experimental setup allows to measure the azimuthal and radial dependence of several plasma parameters. Plasma potential, electron temperature, electron density, electron energy distribution etc. are calculated from the voltage-current characteristics of the probes to investigate the effect of external settings (microwave power, gas pressure) to the spatial distribution of plasma parameters.