The two most critical components to any technical presentation are enthusiasm and expertise. The speaker must be interested in what he or she intends to talk about and the audience must have confidence in the speaker. A speaker cannot convey interest in a topic if he or she does not have an interest in it, and neither can the speaker inform nor persuade the audience without trust the knowledge and judgment of the speaker.
Emotions are contagious: A speaker who is enthusiastic about and displays interest in his or her topic will convey this interest to the audience; yet a speaker who is uninterested in the subject matter will pass this boredom to the audience, as well.
Enthusiasm will have other side effects:
A technical presentation based on the subject matter found in a signal web page found during a Google search will be very shallow and will demonstrate the lack-of-interest from the speaker.
The adjective technical suggests that the speaker has sufficient knowledge on the given material; however, the speaker should never be giving a talk to the limit of his or her knowledge. A talk given to the extent of the speaker's knowledge will, necessarily, be shallow and superficial. The speaker must always understand at least one level beyond the subject being presented, both in general and in detail.
Understanding one level in general implies that the speaker understand the larger context of the presentation as well as related material. A technical presentation on a particular algorithm implies that the speaker should have at least a basic knowledge of related algorithms as well as a history of the particular algorithm being discussed.
As well as understanding the material discussed, the speaker should be aware of all details concerning the topic being discussed. As has already been discussed, a presentation means to inform or persuade in a very short period of time. Not all information can or should be presented in this time; however, the speaker should be able to answer most questions related to the topic. The speaker should be well versed in all technical specifications related to the subject matter.
It should not be possible for an individual to pick up a collection of slides and with minimal coaching give a technical presentation. A technical presentation where the information covered is regurgitated from memory is useless to the audience. An e-mail could have covered the same material.
In a work environment, engineers will be required to give technical presentations on the projects on which they are currently engaged. Consequently, it is likely that they will have a minimal amount of technical interest and knowledge; however, it is always useful to delve further into the material. The Software Engineering program requires that students give their technical presentations based on their first work-term report. This usually ensures that the speaker has a topic which is of interest and where the speaker has technical knowledge.
For example, a number of students have given presentations on Wireless Local Area Networks and covered a basic, high-level overview of IEEE 802.11a, 802.11b, and 802.11g. When asked for the differences between the specifications, no student had any idea as to what the differences were, apart from the very basic information about the frequency, the rate, and the year the protocol was introduced. Either the first hit with a Google search on wireless transmission protocols or wikipedia gives more information about IEEE 802.11* than any of the speaker bothered to research. (Suggestion: don't give a talk on this topic.)
A student chooses a topic and then finds that he or she has no interest in the details of that topic, the it would be best to find a better topic. If this is not possible, a student could find the most interesting aspect about the given topic and focus on that particular angle. The longer a student thinks about the topic, the more likely it is that the student will have a topic which is both sufficiently technical and interesting.