  We demonstrate that the exact solution for the spectrum of synchrotron
radiation from an isotropic population of mono-energetic electrons in turbulent
magnetic field with Gaussian distribution of local field strengths can be
expressed in the simple analytic form: $\left( \frac{{\rm d} \dot{N}}{{\rm d}
\omega} \right)_t
  = \frac{\alpha}{3} \frac{1}{\gamma^2} \left( 1 + \frac{1}{x^{2/3}} \right)
\exp \left( - 2 x^{2/3} \right)$, where $x = \frac{\omega}{\omega_0}\, ;
\omega_0 = \frac{4}{3} \gamma^2 \frac{eB_0}{m_e c}\, .$ We use this expression
to find approximate synchrotron spectra for power-law electron distributions
with $\propto \exp\left( -\left[ \gamma/\gamma_0 \right]^\beta\right)$ type
high-energy cut-off; the resulting synchrotron spectrum has the exponential
cut-off factor with frequency raised to $2\beta/(3\beta+4)$ power in the
exponent. For the power-law electron distribution without high-energy cut-off,
we find the coefficient $a_m$ as a function of the power-law index, which
results in exact expression for the synchrotron spectrum when using
monochromatic (i.e., each electron radiates at frequency $\omega_m = a_m
\gamma^2 \, \frac{e B_0}{m_e c}$) approximation.
