  Weak heating events are frequent and ubiquitous in solar corona. They derive
their energy from the local magnetic field and form a major source of local
heating, signatures of which are seen in EUV and X-ray bands. Their radio
emission arise from various plasma instabilities that lead to coherent
radiation, making even a weak flare appear very bright. The radio observations
hence probe non-equilibrium dynamics providing complementary information on
plasma evolution. However, a robust study of radio emission from a weak event
among many simultaneous events, requires high dynamic range imaging at
sub-second andsub-MHz resolutions owing to their high spectro-temporal
variability. Such observations were not possible until recently.This is among
the first spatially resolved studies of an active region loop hosting a
transient brightening (ARTB) and dynamically linked to a metrewave type-I noise
storm. It uses imaging observations at metrewave, EUV and X-ray bands, along
with magnetogram data. We believe this is the first spectroscopic radio imaging
study of a type-I source, the data for which was obtained using the Murchison
Widefield Array. We report the discovery of 30 s quasi-periodic oscillations
(QPOs) in the radio light curve, riding on a coherent baseline flux. The
strength of the QPOs and the baseline flux enhanced during a mircoflare
associated with the ARTB. Our observations suggest a scenario where magnetic
stress builds up over an Alfv\'{e}n timescale (30s) across the typical magnetic
field braiding scale and then dissipates via a cascade of weak reconnection
events.
