RITA* – the radioactivity thin-layer-chromatography detector – uses a linear analyser detector, which is sensitive over the entire chromatogram trace from start to finish. The entrance window can be open for H-3-applications or closed for C-14 or any other beta- or beta+ radiation emitting nuclides. Many gamma radiation-emitting nuclides are emitting beta radiation as well. The pure gamma emitting nuclides can be detected because they produce some Compton electrons. 

RITA* has 2 simultaneous sensing electrodes: the delay line determines the location of the counted event; the pulse height of the counting wire is used for the electronic collimation. Thus, high energy beta radiation can be detected with high resolution using a narrow collimator window. 

RITA* is an extended version of MARITA that can measure automatically many single traces one after the other. The RITA* detector is elevated after the end of the measurement and moved automatically to the next trace position. Multi traces can be displayed as a 3-dimensional presentation or as a 2-dimensional distribution over the entire 200 x 200 mm TLC plate. 

The counting gas is a non-inflammable mixture of 90% Argon and 10% Methane, which is traded as P10 gas. The gas consumption is very low. 2 TLC plates of 200 x 200 mm each can be placed in RITA* at the same time. 

A metal/glass cover closes RITA* completely and protects the environment as well as RITA* itself from electronic frequency emissions (CE).