  The results of photometric and spectral observations of T CrB obtained in a
wide range of wavelengths in 2011-2023 are presented. We use the near-IR light
curves to determine a new ephemeris $JD_{min} = 2455828.9 + 227.55 \times E$
for the times of light minima when the red giant is located between the
observer and the hot component. The flux ratio H$\alpha$/H$\beta$ varied from
$\sim 3$ to $\sim 8$ in 2020-2023, which may be due to a change in the flux
ratio between the X-ray and optical ranges. It is shown that the value of
H$\alpha$/H$\beta$ anticorrelates with the rate of accretion onto the hot
component of the system. Based on high-speed follow-up observations obtained on
June 8, 2023, we detected a variability of the HeII $\lambda 4686$ line with a
characteristic time-scale of $\sim 25$ min, the amplitude of variability in the
$B$-band was $\sim 0.07^m$. Simulations of the near-IR light curves accounting
for the ellipsoidal effect allowed us to obtain the parameters of the binary
system: the Roche lobe filling factor of the cool component $\mu=1.0$, the mass
ratio $q=M_{cool}/M_{hot} \in [0.5, 0.77]$, the orbital inclination $i \in
[55^\circ, 63^\circ]$. A comparison of the light curve obtained in 2005-2023
with the 1946 outburst template made it possible to predict the date of the
upcoming outburst - January 2024.
