[geordief (OP)]

 I am trying to find an example of an extremely small electric charge moving wrt to  a magnetized conductor and causing  a photon to be created.

I understand that this can be seen as a classical or as a quantum phenomenon and so I would like to understand it classically in as microscopic a way as possible and then to try and understand it in the Quantum explanation (although I anticipate this as  being very challenging  for me)

[alancalverd]

Not sure you need a magnetised conductor. If you accelerate the conduction electrons in a wire, by applying an oscillating voltage, it will emit radio waves in an entirely classical manner as described by Hertz, Marconi et al. If you excite the valence electrons of sodium with a hot flame, some will drop back to their ground state and emit characteristic spectral lines defined by quantum mechanics.

[evan_au]

Probably the easiest case is a CW (Continuous Wave) radio transmitter, used for transmitting Morse Code.

A crystal generates a certain frequency in the radio band, and a large amplifier increases the amplitude.
- This feeds into a vertical antenna wire, moving charge in and out of the wire.
- The antenna wire radiates radio-frequency photons horizontally in all directions
- The frequency of the photons is determined by the crystal frequency

In practice, this would be rather inefficient, because a lot of the charge pumped in and out of the antenna wire results in building up a near-field electric and magnetic fields; these collapse and reverse  when the amplifier reverses the current flow. Only a fraction of the charge that results in far-field radiation which propagates away as photons.
- In reality, a tuned Inductor (L)/capacitor (C) oscillator is fed by a small amplifier
- The energy stored in the near field is recycled through the LC circuit with minimal loss
- The amplifier only needs to make up for the smaller amount of power which is radiated as photons.

See: https://en.wikipedia.org/wiki/Antenna_(radio)

Oops! Overlap with alancalverd