TGV is the measurement of double beta decay of ⁴⁸Ca and ¹⁰⁶Cd. The TGV collaboration (IEAP CTU, JINR Dubna, CSNSM, KU Bratislava, INP) has been interested in experimental investigation of ββ decay for several years. The collaboration measured half-live of two-neutrinos double beta decay of ⁴⁸Ca isotope with the TGV I detector. Based on the experience with the spectrometer TGV I, the more efficient low-background spectrometer TGV II was constructed. The most important feature of the TGV II is its ability to study small amount of materials with high efficiency (especially samples made of isotopes available only in small quantities, e.g. ¹⁰⁶Cd). At present the collaboration TGV is devoted to the investigation of the two-neutrinos double electron capture (2νEC/EC) in ¹⁰⁶Cd. The result of T_1/2 ≥ 3.0 x 10²⁰ years for 2νEC/EC (g.s → g.s) decay of ¹⁰⁶Cd has been found after the processing of experimental data obtained after 8700 hours (1 year) of measuring time using approximately 8 gramme of ¹⁰⁶Cd. The Phase II of this measurement started in December 2007 with appr. 15 gramme of ¹⁰⁶Cd. The Phase II of TGV II experiment is planned for period of 3-4 years.