Shared Flashcard Set

Details

3D153 V1 - U2 SS
Protecting Electronic Equipment
38
Communication
Professional
02/28/2012

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Cards

Term
012-1. What activity must occur to produce an EMP?
Definition
Nuclear explosion
Term
012-2. Which two elements produce the EMP effects?
Definition
(1) Gamma rays.
(2) Secondary neutron radiation.
Term
012-3. What are the electromagnetic pulse forms produced by the derived environment?
Definition
(1) HEMP.
(2) SGEMP.
(3) SREMP.
Term
012-4. Why is high-altitude EMP environment protection important for critical, time urgent mission systems?
Definition
It can affect many systems simultaneously.
Term
012-5. Why is system-generated EMP a problem for satellites and reentry vehicles?
Definition
They are directly exposed to the nuclear radiation from a high-altitude burst
Term
012-6. What are the two distinct regions of importance for SREMP?
Definition
(1) Source.
(2) Radiated.
Term
012-7. What effects on communications are there after a nuclear detonation?
Definition
Scintillation and blackout.
Term
012-8. What capabilities can be employed by Milstar to mitigate communications loss within a contaminated area?
Definition
Crosslink.
Term
013-1. Describe the difference between long-line and local effect of EMP on facilities?
Definition
Long-line effects are the currents and voltages induced on long power lines, communication cable links, or even other conductors, such as pipelines. Some of these EMP effects may be induced far away and guided to the facility along the conductor. Local effects are the currents and voltages induced directly on the facility shield, building structure, wiring, equipment cabinets, and so forth.
Term
013-2. How can a facility be survivable against EMP?
Definition
To create an EMP survivability facility, it should be shielded as much as possible. Furthermore, all openings to the facility need to be filtered and protected. The facility also needs to be isolated from any external electric EM propagation in the earth.
Term
013-3. What happens in an EMP induced event?
Definition
Can cause a magnetic or electric field to be induced in an electrical circuit that can cause an error in the response of the circuit.
Term
013-4. Why is bonding important in EMP protection?
Definition
To ensure a mechanically strong, low impedance interconnection between metal objects.
Term
013-5. Where should all metallic penetrations entering the protected area be located?
Definition
At a common location.
Term
013-6. To reduce coupling into susceptible circuits, what element is installed on both signal and power lines?
Definition
Filters
Term
014-1. What is EMI?
Definition
It is any electromagnetic disturbance that interrupts, obstructs, or otherwise degrades or limits the effective performance of electronics/electrical equipment.
Term
014-2. How do you differentiate an unintentional interference from jamming signal?
Definition
Unintentional interference normally travels only a short distance; a search of the immediate area may reveal the source of this type of interference. Moving the receiving antenna for short distances may cause noticeable variations in the strength of the interfering signal. These variations normally indicate unintentional interference. Conversely little or no variation normally indicates enemy jamming.
Term
014-3. What type of EMI occurs when an unwanted carrier frequency follows the normal signal path through the effected receiver?
Definition
Co-channel
Term
014-4. How can you eliminate broadband transmitter noise?
Definition
By using a band pass filter.
Term
014-5. What type of equipment often generates many spurious emissions?
Definition
Receiver responding to off frequency signals.
Term

014-6. What type of equipment often generates many spurious emissions?

Definition

Rapid tuning transmitter

Term
014-7. What intermodulation frequency components can cause EMI in the receiver/transmitter?
Definition
Sum and difference.
Term
014-8. What type of intermodulation can have a very large bandwidth and cause more severe interference problems than intermodulation products created in either transmitters or receivers?
Definition
Rusty bolt.
Term
014-9. What type of EMI occurs when high level radiated signals penetrate and induce a radio frequency voltage in the internal circuits of a system or equipment?
Definition
Brute force
Term
014-10. What AM receivers are particularly susceptible to power line noise?
Definition
HF and VHF.
Term
014-11. Relays may cause interference inside receivers because of broadband radiated noise originating from what?
Definition
The opening and closing of the contacts
Term
014-12. How would you normally eliminate electromagnetic interference caused by sodium and mercury vapor lights?
Definition
Installing a new bulb
Term
015-1. What is the purpose of the AFSIR program?
Definition
Document and resolve spectrum interference problems
Term
015-2. Under the AFSIR program, what organizational level must begin an investigation to identify the source of EMI?
Definition
Lowest unit level
Term
015-3. Why must you ensure maintenance personnel responsible for the affected equipment check it before submitting an EMI report?
Definition
To ensure the equipment is not causing the problem
Term
015-4. How do you confirm an EMI problem?
Definition
Check with other users of the same frequency and determine whether they receive the EMI
Term
015-5. If your EMI sounds like noise, what are the possible sources of these interferences?
Definition
The source may be power lines, welding equipment, and so forth.
Term
015-6. Who is responsible for recording specific information concerning EMI?
Definition
The operator
Term
015-7. What types of EMIs are exempt from AFSIR reporting?
Definition
USAF units under the operational control of a combatant command, transient EMI from natural sources, suspected or confirmed cause of interference from space weather, interference is only experienced aboard ISR aircraft aloft and is localized when mission equipment or payload equipment is turned on/off or used, and If EMI is only affecting frequencies assigned on a noninterference basis for training purposes.
Term
015-8. How should an AFSIR report be submitted?
Definition
All reports are submitted through their chain of command, through MAJCOM, and to the AFFMA.
Term
015-9. What document contains guidelines for classifying EMI reports?
Definition
CJCSI 3320.02B, JSIR
Term
015-10. What service provided by the 85 EIS analyzes and recommends corrective actions for reported EMI problems?
Definition
QFIRC
Term
015-11. What is the objective of the JSIR program?
Definition
Report and assist with the resolution of EW and recurring EMI
Term
015-12. Who maintains a central database of EMI cases, resolutions, and lessons-learned for all DOD EMI?
Definition
JSC Joint Spectrum Center
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