Understanding Diodes

The following assumes you have already learnt about Diodes but have not fully understood.

Semiconductor Diode Operation
Imagine a girl called Diane Ode going to a football match and coming to a turnstile. To turn the turnstile she needs to have other girls help to push her through. Notice she can only go one way through the turnstile and that is into the football ground. The number of girls needed to push her depends upon the force needed to turn the turnstile. The same applies to semiconductor diodes. Germanium needs less force than silicon.

Diode Rectification
A compressor is our ac supply since the piston is either pushing or pulling. When the compressor is on the downward stroke a valve opens to allow air to be pulled in. A different valve then opens to allow the air to be pushed out. If the compressor outlet is made to turn a fan, the fan would turn in only one direction. The exhaust from the fan is vented to atmosphere but since air is pulled in from the atmosphere by the compressor we have our circuit.

The above is only half wave rectification since it is only when the piston is pushing that a flow to operate the fan is available.

If another compressor is used and pushes when the first compressor is pulling, the outlets of both being connected together, we now have full wave rectification. At any given time that the pistons are moving a flow of air will be available to turn the fan round.