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Thread: Source for ambiguous exam questions- CCTV maximum length

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  1. #1
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    Source for ambiguous exam questions- CCTV maximum length

    Hello all,

    First time reader, first time poster and long time telephone contractor here in the State of CT so please forgive me in advance for any errors in this forum.

    What is a time accurate recommendation for book(s), reference materials or what have you for the C5 low voltage exam In CT? Specifically for the ambiguous questions that are only answered correctly if you know some one who knows. Yes I know, read the NEC 70 and 72 and other code books but I am referring to outdated questions still on the test that you only would come across on a state exam.


    example: Q18 What is the typical maximum CCTV Coax length?

    My response: Ahhh well umm, what resolution are the cameras? 300 lines? 800 Lines? 1920 x1080? Are you using RG11, RG6 RFG59 coax? Composite, S Video, RF modulated video? Are the camera's and monitors a manufactures 'set' that use equalization to compensate and extend for analogue signal loss over coaxial wire? How much loss is acceptable? Color or black and white?

    Obviously this question is as outdated as the 1994 test question: What is the most common type of telephone wire?


    [] Star Quad was the correct answer in 1994 - you know the 4 conductor Gr Rd Blk Yel phone cable used in the 60's and 70's. Star Quad Cable is nothing I have ever seen installed when working at the DPCP in Hartford and the only reason I got that right was my marine buddy was told that was the answer by a building inspector.


    Thank you in advance for your thoughts. This is for both an apprentice under me and I am going to take advantage of the grandfathered T1 to C5 'license upgrade'


    Be Well


    PS does any body else find it rather organized that you can purchase the NEC 2011 as a downloadable PDF, the electrical exam is open book but you can't use a kindle or laptop or tablet at the test center? Who carries paper any more!


  2. #2
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    Quote Originally Posted by 1.42_tera_dynes View Post
    example: Q18 What is the typical maximum CCTV Coax length?
    I hate those questions, and there's no point arguing with the test proctor, they usually don't care. What is a "typical maximum", anyway?

    Quote Originally Posted by 1.42_tera_dynes View Post
    Obviously this question is as outdated as the 1994 test question: What is the most common type of telephone wire?

    [] Star Quad was the correct answer in 1994 - you know the 4 conductor Gr Rd Blk Yel phone cable used in the 60's and 70's.
    Starquad?????? "StarQuad" is a trademark for Carare's microphone cable (which goes back to 1980's). I assume they're referring to D (or is it J, the memory is fuzzy) station cable. Let's use incorrect trademark names in a test, sheesh. The test is wrong on it's face. (Kind of like the people that argue about the names Unistrut and Kindorf.)

  3. #3
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    I took the low voltage tests many years ago and the questions were outdated then. I think the tests lag behind current technologies. Some of the best sources are other technicians or installers that have been in the industry for a long time. If it were me, I would also look at dated installation manuals for low voltage systems. If you are an installer, register for the honeywell security mywebtech and you can look up some pretty old installation manuals. They will have specifics on cable types, wire gauge sizes, installation requirements of their products. If you have the option, work on some older systems and you will see how they were installed and the questions will sometimes be inherently part of your memory.

  4. #4
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    I agree- if they are going to ask questions like that they need to have study guides with the information the questions are based on. Otherwise it's like asking what color socks you wear on a Monday.


    -Hal

  5. #5
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    Thank you all. Now I feel a bit better that I am not alone.

    >I hate those questions, and there's no point arguing with the test proctor<


    I will share another ambiguous question - and since the cat is out of the bag, yes I took the test (no code books as I can only purchase the NEC on line but can't bring a kindle, laptop or other electrical personal device)


    ? A block refers to:

    I happened to see in Art 800 definitions that the term BLOCK is defined as, you guessed it. A city F(*%)(*%) block?

    20 years in the field, its an exam for electrical work so I figured a block was like a 66 block, a telephone termination block, or a BIX or 110 block, or a block of DIDs. I seriously think they wanted the Art 800 definition of a city block!



    Quote Originally Posted by darrell51 View Post
    . . . Some of the best sources are other technicians or installers that have been in the industry for a long time. If it were me, I would also look at dated installation manuals for low voltage systems. If you are an installer, register for the honeywell security mywebtech and you can look up some pretty old installation manuals.. . .
    That's a good idea!

    >>>if they are going to ask questions like that they need to have study guides with the information the questions are based on<<<

    For $ you can get all that junk. Manufacture the cigarettes and sell nicorette.

    This possibly relates to an argument I need to brush up on. Under CTGS any law or ordinance or requirement imposed on an individual or business... the state body must make fair and reasonable access to the understanding/ requirements of said license. Don't quote me on the statute. Just my understanding of several codes and to me it means, if I need a license to drive a car, the governing entity has to provide access to know what the law and rules are in a clear and unambiguous manner. This does not mean they have to pay for my driving school but they have to provide me with the rules of the road.


    I am back to reading my electronic down load of NFPA 70 and 72 to see what other English words I apparently do not understand. If it is OK to do so, I will perhaps start a forum of the 'outdated ambiguous' questions that we all come across if any one feels that could help others; not to cheat but so we can 'perform our duties in a safe and beneficial manner for the people of Connecticut'


    Be Well

  6. #6
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    The answer might be: 1000 feet. That's the longest standard length of a roll of co-ax cable.
    Kevin

  7. #7
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    The answer might be: 1000 feet. That's the longest standard length of a roll of co-ax cable.
    I don't know either but I'll bet if you go back to 1990 CCTV equipment spec sheets and consider only RG-59 solid dielectric and baseband video (6Mhz) you will find your answer.


    Now see, if you were able to access the internet during the test you could look up the spec sheet for RG59 solid dielectric then look at the attenuation chart and see what it is at 6Mhz. Then from the multiple choice answers make an educated guess. But you can't.

    -Hal

  8. #8
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    Quote Originally Posted by 1.42_tera_dynes View Post
    ... >>>if they are going to ask questions like that they need to have study guides with the information the questions are based on<<<

    For $ you can get all that junk. Manufacture the cigarettes and sell nicorette. ...
    uhhh ... why not buy the guides (and the instructors guides while you are at it)

    That was my solution for both my PE ticket and EA ticket. In both exams, there were questions right out of the guide - only the numbers were changed.

    Fighting city hall is fun - making money is more fun.

    If you want to be a hero, join the appropriate organizations after you get your license and take on the Syndicate to your hearts content. I encourage you all I can. Someone has to do it. And I won't. My passion is collecting the money for an excellent, on-time, in-spec, in-budget, job.

    ice
    Harmless flakes working together can cause an avalanche of destruction

  9. #9
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    uhhh ... why not buy the guides (and the instructors guides while you are at it)
    That would be the easy thing to do except that I don't believe they exist for this exam. Wasn't that talked about early on? I think the OP was just assuming in your quote.


    -Hal

  10. #10

    CCTV Maximum Lenth

    I'd have answered 700 feet if it was an option.

    If I recall "most camera manufacturer's" manuals state:
    RG 59 700ft
    RG 6 900ft
    RG11 1100ft

    and RG 59 being the typical size -- I'd go with 700ft.
    Someone else below said 300 feet and I'd go with that if the cabe was old-style 23AWG Copper-Clad-Steel CCTV.

    (If there's science to it, I once was told that the total "loop" voltage drop is to be <1V. Given that, and the DC resistance of the conductors + shield (95% Bare Copper -- itself a hard number to find for each cable size) -- I calculated lengths about 20%-30% longer than the 700 / 900 /1100 camera manuals. And that's probably the safety factor they's use.)

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