  Emission from the active nucleus in the core of the brightest cluster galaxy
of the Perseus cluster, NGC 1275, has varied dramatically over the past four
decades. Prompted by the Fermi detection of flaring in the gamma-ray band, we
present the recent increased activity of this source in the context of its past
radio and gamma-ray output. The broad correspondence between the high-frequency
radio data and the high-energy (HE) emission is striking. However, on short
timescales this correlation breaks down and the 1.3 mm Submillimeter Array flux
is apparently unaffected during Fermi-detected flaring activity. The fact that
NGC 1275 is also detected at TeV energies during the periods of HE gamma-ray
flaring suggests that the short-timescale variation might be primarily related
to changes in the inverse Compton scattering of photons by the electron
population in the jet. The longer-timescale changes suggest a 30--40 year
variation in the fuelling of the black hole, that affects the power of the
inner jet. NCG 1275 is a laboratory for the class of brightest cluster
galaxies, and its variability on these timescales has implications for our
understanding of massive galaxies in cooling-core clusters. The case of NGC
1275 highlights the need for wide coverage across the radio band to correctly
account for the contribution to emission from a synchrotron self-absorbed core
(for example when considering contamination of Sunyaev-Zel'dovich effect
observations), and the danger of variability biases in radio surveys of
galaxies.
