Until I get a transformer I am using a half wave rectifer with all the necessary precautions.

What you have done by using half-wave rectification directly from the mains is to create a very dangerous situation.

In this case, the "necessary precaution" is to disconnect the circuit from mains power until you receive the isolation transformer.

Transformers are a bargain when compared to the cost of a funeral.

 

If anyone is curious, I moved the posts about AC vs. DC waveforms to another thread - http://forum.allaboutcircuits.com/showthread.php?t=30034

The off topic discussion might have diverted from the message here that dealing with unisolated line voltage is extremely dangerous and should always be avoided.