1. Do you know what Is A Ground Loop?

An AC current that can be produced in a cable. This is usually caused by parts of the system being fed from different electrical sources resulting in different earth potentials at each end. The result is interference on the signal, usually in the form of dark bands across the monitor and on occasion tearing in the top third of the image.

2. Tell me what are some of your strengths on the job?

Prepare an answer that emphasizes the skills and requirements outlines in the job listing. Match your abilities to the company's needs and goals, and focus your reply on what makes you stand out from the competition.

3. Tell us what Type Of Illumination Can I Use With Color Cameras?

Only lighting within the visible wavelength should be used with color cameras. Tungsten Halogen is often the recommended source of lighting.

4. Tell us how comfortable are you using computers?

As a security guard, you'll have to use the software associated with CCTV cameras. If you have experience using CCTV equipment, say so. Otherwise, demonstrate computer literacy and an ability and willingness to learn to use new systems.

5. Explain me what Size Monitor Should I Be Using?

The correct size monitor is dependent on its use e.g. the number of images to be displayed at any given time, the viewing distance and the available space.

6. Please explain do I Have To Use A Regulated Power Supply?

In general the answer is yes. Most manufacturers will recommend the use of such power supplies as standard with their equipment. You should always consult the manufacturer's specifications prior to the connection of any power supply.

7. Can you tell me what Is The Correct Level For A Video Picture?

The correct level is 1 volt peak to peak. This can only be accurately set either with an oscilloscope or with a video level meter.

8. Explain me how Do I Connect An Auto Iris Lens To A Camera?

This is usually performed by a simple plug-in connection to the rear or side of the camera. However you should always refer to the relevant camera handbook.

9. Tell us what could cause one to quit working?

Lack of power, broken or damaged internal wires, corroded connectors or improperly assembled connectors can likely cause this to happen. The best recourse is to troubleshoot and find out the exact cause of the problem to repair as needed.

10. How To Eliminate Ground Loop Faults?

This can be achieved in a number of ways, the easiest of which is the installation of a Ground Loop Isolation Transformer. This is best installed at the monitor or recording end of the system.

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