LEARNING OBJECTIVES
Upon completion
hogan of this chapter, you will be able to do the following:
* Identify the various methods of measuring standing-wave ratios.
* Identify the various methods of determining electrical losses caused by deterioration of transmission lines.
* Identify the methods of measuring intermodulation distortion.
QUALITATIVE MEASUREMENTS
As a technician, you are responsible for maintaining and repairing for complex electronic systems. The basic ability to maintain a specific piece of equipment is only the first step in becoming a qualified and perfect technician for
hogan Finest Church Materials an electric item. Your ultimate goal should be to become proficient at systems fault isolation - in other words, to know the entire system like the back of your hand. To reach this goal you will need
isabel marant to be familiar with all parts of the system and know how they are interconnected and interact with each other. There are numerous shortcuts or tricks of the trade that can only be learned through experience on any system, but the most practical thing for you to remember is to approach all problems in a logical manner.
Do you need to achieve a deep understanding of the issues?
I believe that qualitative research has special value for investigating
air jordan complex and sensitive issues.
abercrombie pas cher Decoding SINP in Entrepreneur Category For example, if you are interested in how people view topics like God and religion, human sexuality,
hollister uk the death penalty, gun control, and so on, my guess is that you would be hard-pressed to develop a quantitative methodology that would do anything more than summarize a few key positions on these issues. While this does have its place (and its done all the time), if you
hollister online shop really want to try to achieve a deep understanding of how people think about these topics, some type of in-depth interviewing is probably called for.
STANDING-WAVE RATIO (SWR)
louboutin MEASUREMENTS
Standing-wave ratio (swr) is the ratio of the maximum voltage or current to the minimum voltage or current at any point along a transmission line. Swr measurements are used to determine the matching quality of the termination of the line.
A variety of methods and test equipment's
isabel marant sneakers may be used to measure the voltage or current distribution along a transmission line. An open transmission line is accessible for coupling to many types of voltage-measuring devices, such as a wave meter or a grid-dip meter. However, at higher frequencies where coaxial cables or waveguides are used
abercrombie to minimize skin effect losses, (discussed in NEETS, module 10) access is more complicated. Access to the interior of the waveguide or center conductor of the coaxial cable must be gained by using a unidirectional or bidirectional coupler, which is inserted into the transmission line. The coupler contains a slot into which an rf probe is inserted and positioned with respect to directivity.
Check this awesome Inverse Square Law Formula - i recently used.
POWER OUTPUT VERSUS IMPEDANCE MATCHING
For maximum transfer of the power
abercrombie out of an rf source, with minimum heating from reflected power, the total output impedance sensed by the rf source must be equal to the internal impedance of that source. A perfect impedance match between transmitter and load would exist if the swr were 1 to 1. As discussed in
karen millen outlet NEETS, module 10, test equipment designed to measure the instantaneous voltage of a standing wave will give you a voltage standing-wave ratio (vswr). Test equipment designed to measure the instantaneous current component of a standing wave will give you the current standing-wave ratio (iswr). Regardless of the type of test equipment
air jordan selected, both ratios will be the same.
Developed for scientific research, qualitative observation can be a useful tool for employee and organizational development. Managers and human resources professionals use it for job analysis, employee performance evaluations, and identifying problems or opportunities for
abercrombie pas cher improvement. Organizations use it in conjunction with quantitative data (such as statistics) or to evaluate subjective perceptions.
What It Is
In qualitative observation, managers and human resources representatives study a work situation, including the employees, to identify and understand the various aspects of the situation and how employees interact. In the process, the evaluator documents the observations in some form to record behavior, events, tasks and duties. The information collected can then be analyzed.
How It Works
The person conducting a qualitative observation uses a standard protocol---such as a worksheet, a checklist or a rating scale---to evaluate tasks, work skills and employee behaviors. The observer may also write a description about the observation.
For example, nurse preceptors often use a "clinical performance evaluation" packet to help train and evaluate new nurses. The packet includes a checklist of all the required tasks and a performance evaluation scale for each task ranging from 1 (dependent) to 4 (independent), according to the Texas A & M University's Nurse Preceptor Handbook.
Methods
Managers may use a simple observation approach that involves observing and recording employee behavior and work efforts. The observer may refrain from making comments or asking questions. For example, a manager might watch workers in a shipping department via closed-circuit video to discover why orders are not being shipped in a timely manner. Such observations can help the
abercrombie pas cher Are Low priced E-cigs Nonetheless Super manager identify employee training needs or performance issues.
In participant observation, the observer takes part in the task or work being observed. Observers use that method for job analysis and process improvement initiatives. For example, an observer may work in a library, interacting with librarians, library assistants and patrons to identify ways to improve customer service.
Observers may also review available information about the workplace, interview employees, or conduct focus groups with employees who do the same or related work.
Chat Sentinela
