lThe equivalent frequency at the maximum current intensity of Debye peaks obtained by the thermally stimulated depolarisation current technique (TSDC) was discussed and its dependence on the Arrhenius parameters was calculated. The effect of the heating rate was also considered. Some specific virtual situations (zero entropy behaviour and compensation phenomena) were compared with experimental results on 11 non-conventional polymers near and below the glass transition temperature. For one such polymer, the temperature dependence on the frequency of the alpha- and beta-relaxation observed by dielectric relaxation spectroscopy was compared with the results obtained by thermally stimulated discharge current in the glass transition and sub-T-g regions.