A new and simple technique has been developed using plastic scintillator detectors for gamma ray and
cosmic ray spectroscopy without single channel analyzer (SCA) or multichannel analyzer (MCA). In these
experiments only a leading edge discriminator (LED) and NIM scalers have been used. Energy calibration
of gamma spectra in plastic scintillators has been done using Co60 and Cs137 sources. The details of the
experimental technique, analysis procedure and experimental results have been presented in this paper