  We report the discovery of 74 new pulsating DA white dwarf stars, or ZZ
Cetis, from the data obtained by the Transiting Exoplanet Survey Satellite
(TESS) mission, from Sectors 1 to 39, corresponding to the first 3 cycles. This
includes objects from the Southern Hemisphere (Sectors 1-13 and 27-39) and the
Northern Hemisphere (Sectors 14-26), observed with 120 s- and 20 s-cadence. Our
sample likely includes 13 low-mass and one extremely low-mass white dwarf
candidate, considering the mass determinations from fitting Gaia magnitudes and
parallax. In addition, we present follow-up time series photometry from
ground-based telescopes for 11 objects, which allowed us to detect a larger
number of periods. For each object, we analysed the period spectra and
performed an asteroseismological analysis, and we estimate the structure
parameters of the sample, i.e., stellar mass, effective temperature and
hydrogen envelope mass. We estimate a mean asteroseismological mass of <Msis>_~
0.635 +/-0.015 Msun, excluding the candidate low or extremely-low mass objects.
This value is in agreement with the mean mass using estimates from Gaia data,
which is <Mphot> ~ 0.631 +/- 0.040 Msun, and with the mean mass of previously
known ZZ Cetis of <M*>= 0.644 +/-0.034 Msun. Our sample of 74 new bright
ZZ~Cetis increases the number of known ZZ~Cetis by $\sim$20 per cent.
