by Radical Writer

Created on: October 16, 2009

I'm an electronic technician so I have been repairing these types of low voltage systems for a very long time at least twenty years. Most systems have a low voltage and High voltage area. If the main power source is where you plug it into the wall outlet you have 120 Volts Alternating Current (AC) then this will ultimately be reduced either outside through an adapter which will reduce it and change it over to Direct Current. (DC) or internally through a step down transformer and then switched over to DC. Sometimes the regulator is an AC type which is basically a step down transformer from 120 AC to 12 or 24 volts AC and the distributed to the piece of equipment for usage.

After the change over the systems typically use 5 volts and 12 so they are done so using regulators in which a higher DC voltage is split from a typical 24 Volts DC to two separate voltages and then put through the Regulators to be used by Transistors which are most encapsulated inside Integrated Circuits (ICs). Today it is rare to see transistors in Low Voltage systems except in the power supplies themselves where the AC source first goes into. Today they also use what is called a switching transformer in which a raw AC may be put through some Higher voltage Transistors and they switch half of the AC wave causing a Voltage spike that can be regulated in frequency to cause the switching transformer to work where inside the transformer this voltage is induced across the secondary portion of the Transformer to be used through out the Electronic equipment.

They use this type most now because it can be regulated easier I believe but after working on a few of them I wish the would have stuck to the older and in my opinion better systems. I usually try to replace the entire power supply in these type of systems instead of just replacing a few diodes and a couple Capacitors in the older but better electronic power supplies. If I were to build a power supply for a Computer I would definitely use the older type for myself because I know it would out last the rest of the computer and their would be way less heat to deal with as well. The switching type of power supplies are very hot all the time because of the transistors being used to make these half wave circuits.

Even these low voltage circuits are potentially dangerous in high voltage areas and any voltage of 40 volts can be lethal if enough current is available and all AC supplies 120 or 240 are lethal although they may not kill you don't let your mistaken judgement be your grave marker. If you have a volt meter use it and be certain you have it on DC for direct current systems and AC for Alternating systems because if its on DC and you are checking an AC voltage it won't show you any reading so touch it and you will get a shock and you may die. One of my sons put the end of a DC adapter in his mouth not knowing it was plugged into the wall 24 volts DC. He was very severly shocked and he will never do it again I assure you.

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