Where have all the car radios gone?

[Murphyv310]

Head unit designation started when there were add on units elsewhere in the car like 6 disc players, remote amplifiers etc. It's now stuck in the trade but as Mark says they usually have all the circuitry in the one unit.
Sam you've answered your own question, there is too much debris and vibration in a tractor for CD and tape decks will also wear in a tractor..... Ive had many ruined car CD radios to fix from farmers