Well, I promised a pair of articles about power supplies and have not yet followed through on that promise. What follows is a look at what are probably the most commonly used power supplies, those of the linear variety.

The biggest advantage to linear power supplies is that they are less likely to interfere with radio equipment. The power supplies in computers are switching power supplies and this works well, however, computers do not depend on radio frequencies to perform their tasks.

One thing that is more an advantage for linear power supplies than advantageous about them is that they have been available for many years and people are generally more familiar with them and thus more likely to purchase them.

Other advantages of linear power supplies are that they are said to be quieter and more reliable than their switching counterparts. This can be beneficial in situations where you want to keep the ambient noise levels down and reduce the chances of problems and downtime.

Another advantageous feature that many people find very nice about linear power supplies that most switching power supplies do not offer is that they often come with variable controls that allow the user to change the voltage and/or power output of the power supply. These controls allow the power supply to be used for a variety of applications that requiring different voltages or amounts of power, just not at the same time.

Linear power supplies do have disadvantages that switching power supplies are able to overcome. The biggest two disadvantages of linear power supplies that switching power supplies overcome are their size and weight. Linear power supplies are historically quite heavy. A power supply that is rated to 25 Amps continuous duty with peak output of 35 Amps will weigh somewhere between 25 and 30 pounds and take up about a 12 inch by 12 inch space in your workspace and stand about 6 inches high.

One other disadvantage worth noting is that it has been said that the efficiency of linear power supplies leaves a bit to be desired. For a look at the alternative, I will talk about switching power supplies in an upcoming post.