RR Lyr is one of the most studied variable stars .
Its light curve has been regularly monitored since the discovery of the periodic variability in 1899 .
Analysis of all observed maxima allows us to identify two primary pulsation states defined as pulsation over a long ( P _ { 0 } longer than 0.56684 d ) and a short ( P _ { 0 } shorter than 0.56682 d ) primary pulsation period .
These states alternate with intervals of 13-16 yr , and are well defined after 1943 .
The 40.8 d periodical modulations of the amplitude and the period ( i.e .
Blazhko effect ) were noticed in 1916 .
We provide homogeneous determinations of the Blazhko period in the different primary pulsation states .
The Blazhko period does not follow the variations of P _ { 0 } and suddenly diminished from 40.8 d to around 39.0 d in 1975 .
The monitoring of these periodicities deserved and deserves a continuous and intensive observational effort .
For this purpose we have built dedicated , transportable and autonomous small instruments , Very Tiny Telescopes ( VTTs ) , to observe the times of maximum brightness of RR Lyr .
As immediate results the VTTs recorded the last change of P _ { 0 } state in mid-2009 and extended the time coverage of the Kepler observations , thus recording a maximum O-C amplitude of the Blazhko effect at the end of 2008 , followed by the historically smallest O-C amplitude in late 2013 .
This decrease is still ongoing and VTT instruments are ready to monitor the expected increase in the next few years .