High-precision measurements of angular correlations in neutron beta decay address a number of questions which are at the forefront of particle physics. For a new generation of beta decay experiments, like the PERC (Proton Electron Decay Channel) experiment currently under construction in Munich, frequency-based beta spectroscopy methods using the cyclotron radiation emitted by electrons in a homogeneous magnetic field have been emerging as a new method for high-precision energy measurements. PERC is the successor of the PERKEO-III, which is the experiment of the PERKEO group, and was designed to perform precision experiments of the weak interactions. It established pulsed neutron beam technique that made it possible to study free neutron decay without background. In this talk some latest PERKEO-III results and the status update for the PERC experiment will be presented. Design study of the CREScent experiment, a proof-of principle experiment aiming to combine the CRES (Cyclotron Radiation Emission Spectroscopy) - technique with the signal amplification qualities of a RF cavity, will be introduced.