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TUCoPS :: TV, Cable, Satellite :: videofaq.txt

US/Canada Consumer Video Frequently Asked Questions





Archive-name: rec-video/us-ca-consumer-video-faq
Rec-video-archive-name: us-ca-consumer-video-faq
Version: $Id: FAQL.US-CA.Consumer,v 1.5 1994/02/15 22:47:46 long Exp $

US/Canada Consumer Video FAQL (Frequently Asked Question List)

This release of the US/Canada Consumer Video FAQL (Frequently Asked
Question List) for this group (rec.video) also contains a 'Resource
Guide' for rec.video and VIDEOTECH readers.  This FAQL does not cover
the subgroup rec.video.satellite.  It also does not discuss software
(prerecorded material - such as cult movies - on tape or disc ).  Many
sections have been revised (particularly in the area of laser video
disc - as I now have one - but for a comprehensive treatment of many
technical video subjects read Bob Nilands articles as they have much
more depth than we can/will go into here).

The primary purpose of listing commonly asked questions and their
(supposed) answers here is to cut down on 'noise to signal' content
ratios within rec.video.  As such it is oriented towards neophytes and
is skewed more towards lowest common denominator systems rather than
high end equipment.  It is also USA-centric and NTSC-philic.

This list does not attempt to track the ever changing names and prices
of consumer and prosumer video gear.  Some rough trends and some
features to use when evaluating components are listed.  I am debating
whether or not to list specific vendor recommendations or not.  I am
looking for comparisons and listings of features/checklists for 27"
TVs, camcorders and vcrs to include here.

I am still counting on persons more knowledgable than myself in areas
(such as broadcasting technology, HDTV, BETA, video standards and audio
issues).  Please send me corrections to answers and new questions you
feel should be included.  Apologies for any non-objectivity you may
find in some of my answers.  Help supply some of the ????? data!!!
^L
===============================================================================
TABLE OF CONTENTS
===============================================================================
QUESTION INDEX                  (enumerated index of questions)
GENERAL
BROADCAST TELEVISION                                            (VHF/UHF/etc.)
CABLE TELEVISION                                                (CATV)
CAMCORDERS, SEPARATE & STILL VIDEO CAMERAS
STANDARDS
VIDEOCASSETTE RECORDING/PLAYING         ([S-]VHS/[ED-]BETA/[Hi-]8MM/0.75"/etc.)
LASERDISCS & OTHER VIDEO DISC FORMATS
AUDIO
^L
===============================================================================
QUESTION INDEX                  (enumerated)
===============================================================================
1.      What are good prices ranges for video equipment today?
2.      What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?
3.      What is MTS?
4.      What is SAP?
5.      Why don't Cable companies use the same VHF channels for local stations?
6.      Cable company audits, detection, rules, legality.
7.      My cable descrambler box Channel X (2/3/4) output vs. VCR tuner
8.      Why do camcorder batteries hold less and less of a charge?
9.      How good are consumer DC camcorder lights?
10.     Define the terms : Lux, Zoom, and Pixels
11.     "Which Camcorder should I buy?"
12.     Sony V-series (450,000 pixels) vs F-series (270,000 pixels) models...
13.     Are there Television monitors and VCRs that are compatible with...
14.     Are there kits and plans for RGB to composite video, Y-C, etc?
15.     Why do I get a scrambled mess when I try to copy pre-recorded tapes?
16.     Is there a way to remove Macrovision?
17.     What is an S-Video (aka Y/C) connector?
18.     What are the upper resolutions of different video devices?
19.     What is Dolby 'Surround' and Pro-logic Sound, SRS, THX?
20.     What is a frame vs a field?
21.     What is 'field motion'?
22.     What does 'lines of resolution mean? 
23.     NTSC has 525 what???
24.     What is CLV, CAV, PCM, digital vs. linear audio tracks, etc.?
25.     What is the proper way to store video tapes?
26.     Now I am totally confused as to how one should store video tapes...
27.     Are head cleaners bad?  What is the best way to clean heads?
28.     What is HiFi sound and how is it recorded on tape?
29.     "What is the story behind VHS (& the lack of SVHS) LP mode?"
30.     What is the VCR+?
31.     "Which VCR should I buy?"
32.     Can you put a hole in VHS tapes to record in SVHS mode on them?
33.     How come the RF output from my VCR/LD (one Channel 3/4/X) lacks MTS?
34.     Is the video on laserdiscs (LDs) digitally encoded?
^L
===============================================================================
GENERAL
===============================================================================
Glossary - General Video Hardware
---------------------------------
BNC             British Nut Connector
SCART           European standard multipin connector.  Can be used for both
                composite and Y/C video input/output.
RCA jacks       AKA "phono plugs"
RF jacks        Radio Frequency coax hubs.
                RF outputs from camcorders,vcrs,laserdisc
                players, etc. provide combined audio and video as a
                broadcast signal (usually on VHF channel 3 or 4).  Lower
                quality than baseband (RCA or BNC jacks) inputs/outputs and
                Y/C connectors.
S-Video         Multipin Connector with separate luminance & chromanance.
---------------
1.      What are good prices ranges for video equipment today?

        27" NTSC (US) TV, 400+ lines res, MTS/SAP, Y-C & multiple A/V
        jacks (in&out), stereo speakers, ~180 ch. cable ready.  $500

        (assume tuners built into these)
        2-head VHS VCR                  $150
        2-head VHS VCR,HQ               $200
        2-head VHS VCR,HQ,HiFi          $250
        4-head VHS VCR,HQ               $250
        4-head VHS VCR,HQ,HiFi          $300-360
        4-head SVHS VCR,HQ,HiFi         $500    JVC47000, Pana PV4167
        6-head SVHS VCR,HQ,HiFi         $600+

        Hi-8            camcorder       $1150   Sony CCD V801
        Hi-8            palmcorder      $900    Sony TR-81
        SVHS (full or compact)camcorder $850            
        8mm             camcorder       $750
        VHS             camcorder       $600


2.      What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?

        Letterboxing

        Putting the entire film frame (as seen in the original aspect
        ratio, usually one where the ratio of the length of the
        horizontal dimension over the vertical measurement is greater
        than 1.33 to 1) inside the TV image (which is a more squarish
        shape which can be expressed as 4/3) resulting in black
        (although other colors are sometimes used) bars at the top and
        bottom of the screen (the amount depending on the aspect ratio
        of the film).  You can see this often on MTV.

        Windowboxing

        Similar to Letterboxing except that there are vertical bars on
        the sides of the inset image (as well as horizontal bars) as if
        to prove 'this is the original frame as shot' similar to when
        35mm and 2.5" negatives are printed with the original borders.
        Compensates for overscan on overscanned sets. Seen on TNT.
        
2.      What do the terms 'letterboxing','windowboxing', 'Pan&Scan' mean?
^L
===============================================================================
BROADCAST TELEVISION                                            (VHF/UHF/etc.)
===============================================================================
Glossary
---------------
AFT             Automatic Fine Tuning   - TV/VCR station frequency lock
MTS             Multichannel Television Sound.  US stereo television
                transmission standard.  Up to 15KHz frequency response.
SAP             Secondary Audio Program.  3rd audio channel provided in
                conjuction
UHF             Ultra High Frequency. US Channels 14-69.
VHF             Very High Frequency. US Channels 2-13.
---------------
3.      What is MTS?

        It is a method of broadcasting stereo within the frequency
        range reserved for each TV channel.

        And less frequency range (to 15KHz) than VHS HiFi (up to 20KHz) --
        it rolls off low, like an FM signal.
        But videotape HiFi has all the problems associated with a compander,
        e.g., breathing.
                [credit Andrew Klossner andrew@frip.wv.tek.com]

4.      What is SAP?

        It is a method of broadcasting a second audio channel (often a
        translation into another language) within the frequency range
        reserved for each TV channel.
^L
===============================================================================
CABLE TELEVISION                                                (CATV)
===============================================================================
Glossary
---------------
AFT             Automatic Fine Tuning   - TV/VCR station frequency lock
CATV            Community Antenna Television is the antiquated name for cable.
HRC             A CATV Channel frequency allocation scheme.
IRC             Another CATV Channel frequency allocation scheme.
MTS             Multichannel Television Sound.  US stereo television
                transmission standard.
SAP             Secondary Audio Program.  3rd audio channel provided in
                conjuction
STD             Another CATV Channel frequency allocation scheme.
UHF             Ultra High Frequency. US Channels 14-69.
VHF             Very High Frequency. US Channels 2-13.
---------------
5.      "Why don't cable companies carry VHF stations on their cable on
        the same frequencies they occupy in the air (VHF channel 3 on
        VHF 3, VHF channel 8 on VHF 8) where they exist?"

        Terrible ghosting.  The cable company's signal lags the
        leaked-in broadcast signal by an inch or two or horizontal
        spacing.  My cable company does this on one channel, and I hate
        it.
                [credit Andrew Klossner andrew@frip.wv.tek.com]

6.      And while we're discussing these (very interesting) topics, can
        someone in-the-know briefly explain how, for example, a
        rapacious cable company would detect 1) a "universal
        descrambler" from a Radio Electronics article, 2) a second TV
        connected in another room (believe it or not, some cable
        companies have the unmitigated greed to want to charge EXTRA to
        hook up a second TV in a bedroom, for example. Contrast this
        with the phone company, which charges you for the LINE, not how
        many phones you have connected to that line. But I digress...
        ;-) 3) How such detection can be circumvented.
        -       scott@blueeyes.kines.uiuc.edu (Scott Coleman)

        [DISCLAIMER: Doing anything with the CATV coax coming into your]
        [house other than connecting it to Cable Co. equipment or      ]
        [directly into ONE TV or VCR is considered illegal in most     ]
        [cable franchises (theft of service).                          ]
        [This FAQL answer in no way endorses such behavior.            ]

        1)      The R-E article box only accepts NTSC composite
                video input, therefore no one would detect it.
                It requires an external RF tuner if you want to feed
                a channel into it (such as the RCA connector labeled
                'video out' on the back of most VCRs).

        2)      TDR? (Time Domain Reflectometer - can show the 
                electrical topology of a cable) and or RF leakage
                (backwash).  Although many modern cable unscrambler
                boxes are 'addressable' by the central Cable Co. office
                many rec.video people don't believe they are 2-way
                (is this a fallacy?).  I am not sure whether the
                cable co. can measure the load you are placing on the
                coax cable - but if you are not using a powered splitter/
                signal strength amplifier you will soon see that having 2
                sets on one cable will result in a weaker/worse signal.

        3)      Pass the CATV signal through something that will
                isolate, clean up, amplify and shield from RF
                interference before distributing it to non-sanctioned
                equipment???  Some splitters, or daisy chain the CATV
                coax from VCRs to TV (or vice versa).


7.      Why does cable descrambler box only output on Channel X (2/3/4),
        rendering my VCR useless for recording premium channels?

        Check and see if your cable box can be programmed or if you
        can obtain a timer/remote for it from your cable co.
        A VCR+ might make your life easier (elsewhere in this FAQL).
        There are some TV/Monitors and VCRs that have multiple RF inputs
        (and often multiple RF outputs) - these are sometimes labled 
        Antennae and CATV.  You can have the unmucked cable coax connected
        to the RF input labeled CATV and the output from the converter
        box connected to the RF input labeled Antenna (assuming you aren't
        using an antenna).  In some case you are provided with an RF output
        labeled 'decoder loop' that you can run to your converter box
        (so that you don't need an RF splitter).

^L
===============================================================================
CAMCORDERS, SEPARATE & STILL VIDEO CAMERAS
===============================================================================
Glossary
---------------
AE              Automatic Exposure (Iris, and possibly shutter) 
AF              Automatic Focusing (IR or image sharpness method)
AFM             Audio Frequency Modulation - audio method for encoding on tape.
CCD             Charge Coupled Device - one of the two different types of
                        solid state devices that replaced video tube technology.
IR              Infra-Red.  Light frequency below red in the (visible) spectrum.
                Used by some AF systems (mostly older) and remote controls.
Lux             Light Intensity measurement.
MOS             Metal Oxide Semiconductor - one of the two different types of
                        solid state devices that replaced video tube technology.
PCM             Pulse Code Modulation - audio method for encoding on tape. Rare.
---------------

8.      Why do camcorder batteries hold less and less of a charge
        after many uses?  Is there anything I can do about it?

        A memory pattern effect occurs (NiCad rechargable batteries
        'learn' a memory pattern of past charge levels) but is somewhat
        overrated.  What most users see is really the fast discharge
        rate of a NiCad (they will discharge much more quickly than
        Alkaline batteries when both are sitting on a shelf not being
        used).

        You shouldn't really charge a NiCad frequently (if you are just
        going to store it) or continually top it off after use unless you
        need to use it for a full cycle again right way - you will just
        be wasting cycles in the life of the NiCad (~ 500 - 1000 cycles).
        On the other hand NiCads should NEVER be fully discharged
        or reverse charged - this can shorten the life and even
        damage the battery (some people use home-brew methods such as
        paperclips and lightbulbs to short and discharge the battery).

        Some posters in sci.electronics have suggested sparking the
        batteries with a good jolt from a car battery to get them
        to forget the memorized pattern.  While this might work to
        blast away the filaments of material shorting individual cells
        it may result in an explosion and is not endorsed here.
        An electrolytic capacitor can be used for this purpose,
        be careful out there....

        According to much popular wisdom (in the 'Info-Hams' mailing
        list) many of the commercial products (D'Charger, etc.) are
        harmless at best and shorten the life of your battery at worst.
        Most new camcorder battery chargers (both the camcorder vendor
        and 3rd party 'quick' chargers) stop charging them (overcharging)
        after they are fully charged and some units perform 'pulse'
        charging (preferred).

        You need to be careful to use a charger that is appropriate for
        your NiCad battery.  Some 'quick-chargers' can build up gas
        pressure quickly in batteries that are not designed for them.

        Some full size systems and lights use sealed lead acid
        (sometimes called gel-cells) that do not like full discharge,
        they should be stored charged, and topped off to keep them at
        full charge.  Storing them discharged is bad for them.

        [credit : larson@snmp.sri.com (Alan Larson),
                instructions in my SunPak camcorder light battery,
                "Hugh_E._Wells.ElSegundo"@Xerox.COM,
                popular wisdom in the 'Info-Hams' mailing list     ]

9.      How good are consumer DC camcorder lights?

        Most of the 20-30 watt DC units are only good for 10-20 feet.
        And the batteries last for less than a hour (although you can
        get Pro units that will last for 2 hours or longer they
        generally require external battery packs).

10.     Define the terms : Lux, Zoom, and Pixels

        Lux - Light sensitivity.  1 lux is the light from one candle (?).
        Most 1 lux cameras use electronic enhancement to obtain an image
        (and the quality is not very good at one Lux - but hey, neither
        is Ektachrome pushed to 1600 ISO!).

        Zoom - Most camcorders have a zoom lens which can capture a range
        of angles of view from wide through (what is considered) normal
        to telephoto.  The 'X' rating is the number of 'times' the
        image is magnified (optically) at the highest setting (as in
        binocular ratings).  Most camcorders have 6x1 (low),8x1,10x1
        or 16x1 (high-end) ratings.

        Pixels - Picture Elements.  Individual light gathering elements
        (usually) on a chip.  Analogous to 'rods' and 'cones' in our eye.
        Better camcorders have over 400,000 pixels.

11.     "Which Camcorder should I buy?"

        The answer depends on many factors.  Do you want the best 
        possible or the best price/performance in a particular class?

        I would not recommend BETA to newcomers to the field unless
        you are willing to put up with compatibility problems.
        If you want to go BETA then you know what you are doing
        (and up against).  VHS has won the consumer VCR market,
        even Sony makes VHS & SVHS equipment now and Sony's real path
        for the future is in 8 and Hi-8 mm.

        If ease of use is your criteria and you own a VHS VCR then you
        should look at VHS or VHS-C (a 20 minute compact format)
        camcorders - you can playback your cassette using your VCR.

        If portability and weight (but not human induced jitter) are
        your concern you might want VHS-C, S-VHS-C, 8mm or Hi-8.

        If capturing high quality video for display now or in the
        future is a concern then I would go with S-VHS[-C] or Hi-8.

        If audio is a concern then look for a unit with HiFi Stereo
        (Minolta 8-808. Sony V-101 has AFM.  Olympus VX-H804 has
        PCM Digital Stereo).

12.     Sony spec says that V-series models have 450,000 pixels per
        image while F-series models have 270,000 only. I am curious if
        this difference matters since our VT (not HDVT) has a fixed
        number of pixels anyway.  Am I wrong or V-series models are
        really meant for our grandson's- generation?     
                [credit: zhu@wobbegong.cs.indiana.edu (Zheng Zhu)]

         The CCD on Hi8 picks up at about 410,000 pixels and the Hi8
         systems records at about the same "level" (in quotes because
         pixels are transmuted into horizontal lines of resolution but
         it is about the same)... Regular 8 CCD (CCD is the
         charge-coupled-device pickup "tube" of the camera) handles
         about 270,000 pixels altho there are a few regular 8 CCD with
         higher pixel resolution even if the taping system can't
         actually record that high a resolution.  Still results in a
         better picture but nowhere near as good as Hi8.

         Not meant for your grandson, meant for now, if you want to pay
         the price (you also have to buy a Hi8-capable monitor if you
         want to see ALL of the difference, but you will see some of it
         even on a regular monitor or TV).
                [credit: jfr@locus.com (Jon Rosen)]

^L
===============================================================================
STANDARDS
===============================================================================
Glossary
---------------
HDTV            High Definition Television.  Megapixel display systems
                proposed for the US.  Japan and Europe have already selected
                HDTV standards.
NTSC            National Television Standards Committee.  Video signal used
                (broadcast,tape&disc) in the US, Japan and Latin America.
PAL             Phase Alternate Line.  Video signal used (broadcast,tape&disc)
                in most of Europe (and the parts of the world where NTSC &
                SECAM are not used).

RGB             Video signal composed of separate signals for Red, Green &
                Blue.  Many computer monitors (especially higher resolution)
                are often RGB.
SECAM           Sequential Color and Memory.  Video signal used (broadcast,
                tape&disc) pour les hommes Francais et what used to be
                known as the 'Eastern Bloc'.
---------------
13.     Are there Television monitors and VCRs that are compatible with
        multiple video signal standards (PAL, NTSC, SECAM)?

        Yes. Contact Panasonic, Instant Replay (800-749-8779) and others.

14.     Are there kits and plans for RGB to composite video, Y-C, etc.
        and vice-versa?

        Yes.  Find an index for Radio-Electronics magazine at your
        local library.

15.     Why do I get a scrambled mess when I try to copy pre-recorded tapes?
        (scrambled mess is defined as wavering lucidity followed by
        total darkness).  Am I going crazy?

        No.  This is called Macrovision.  It is a copy-protection
        scheme adopted by the home video industry which works by
        varying the video signal gain level causing VHS VCRs to
        track it into video oblivion.

16.     Is there a way to remove Macrovision?
        (because it bothers my TV/monitor with its flickering, of course)?

        [DISCLAIMER: According to FBI warnings on most prerecorded  ]
        [videotapes, copying copyrighted material is illegal.  This ]
        [FAQL answer in no way endorses such behavior.              ]

        There are ads in the back of VIDEO & Radio-Electronics
        purporting to do this.  Some posters say the RXII works well
        ($49 in VIDEO).  Some posters have asked about Y/C cable-ready
        versions : there is now one advertised called the MT IIS
        ($99).

        It is reported that some (older) Beta units are immune to
        Macrovision.  Copying to and then from these Beta machines is
        said to remove it also.  This is apparently not the case with
        some (newer?) Beta units 

        [credit: Scott Coleman scott@blueeyes.kines.uiuc.edu]

        Some camcorders are reportedly immune also and some posters have
        claimed that they can fix up the signal by running it through a
        monitor/tv with AV inputs/outputs.

17.     What is an S-Video connector?

        Also known as Y-C (and sometimes incorrectly referred to as
        SVHS - which is a tape format) it is a cable and connector that
        carries separate lumina (brightness) and chroma (color) signals
        (vs.  composite, in which both - and sync, etc. - are carried
        on the same wire).  This generally gives a better picture on
        those monitors that support it (especially if the source is of
        high quality & resolution).  It is almost always a win to use
        S-Video cable when you already have a high quality video signal
        that has been separated into separate chroma and luminance and
        want to carry it to another component.

18.     What are the upper resolutions of different video devices?
        ( and broadcast standards? )

        HDTV    ????
        IDTV    ????
        SuperNTSC????
        Projection TV   800     (Good quality)
        D-1             720   (specific since it's digital)
        D-2             768
        Video monitors  500-700 (Good quality)
        ED-Beta         500+
        Hi-8            425+
        LaserDisk       425
        CCD 4XX,000 pix 410-450 CCD camera with ~4[15]0,000 pixels/image
        SVHS            400-425
        HiBand Beta     400
        Standard US TV  350
        BI              350
        3/4" -SP        330
        Super Beta Is   330
        Broadcast NTSC  330
        8mm             300
        Beta IIs        300
        SuperBeta       290
        CCD 2XX,000 pix 270-300 CCD camera with ~270,000 pixels/image
        Beta II         250
        VHS(SP)         240-250
        Beta            240
        VHS(EP)         220

        Note that Bob Niland's evaluation of the new Sharpvision LCD
        projection system has shown that you need to be aware of the
        number of lines of vertical resolution (usually counted as the
        entire frame: the sum of the interlaced field lines or around
        250 x 2 = ~ 500 lines because of the persistence of the phosphor).
        The Sharp LCD projector displayed both video fields, but in
        only ~250 lines (both fields on top of each other, giving a
        lower resolution image - more square LCD dots).

19.     What is Dolby 'Surround' and Pro-logic Sound, SRS, THX?

        These are methods of extracting spatial information from
        encoded stereo audio channels (in some cases they can
        be used to synthesize spatial relationships as well by separating
        frequencies and sending them to different speakers).

        See the following by Bob Niland (rjn@hpfcrjn.FC.HP.COM):
        Intro to Surround Sound Part 1 of 2     Revised: 18 Feb 90
                                Part 2          Revised: 06 Sep 90

20.     What is a video frame vs a field?

        NTSC displays two fields of video (each ~ 250 lines each)
        interleaved to create the illusion of an 'image'.  
        
21.     What is 'field motion'?

        When freezing a frame (2 fields) with a frame store or VCR, the
        fields may have samples from different times.  This can cause a
        very visible flicker fluttering back and forth from the 2
        positions.

        My old Panasonic PV-1650 VCR did this.  The Sony TR-5 camcorder
        does this (which really ruins the advantage of the high-speed
        shutter.)       [credit: larson@snmp.sri.com (Alan Larson)]


22.     What does 'lines of resolution mean? 

        The number of lines that can be shown...
        The vertical resolution is fairly fixed around 480 - 488 for
        NTSC, and is because there are that many lines shown.

        The horizontal resolution depends on the frequency response of
        the system, and is 3/4 the number of vertical lines that could
        be seen on the screen.  The 3/4 is a scaling to the vertical
        size, so lines of equal width will result in the same number.

        A quick relation is that there are about 80 lines of resolution
        for each megahertz of video bandwidth.  Since the performance
        of consumer video equipment is such that the upper frequency
        response is not a sharp point, this number is somewhat
        imprecise.
                [credit: larson@snmp.sri.com (Alan Larson)]

23.      NTSC has 525 what???

        The 525 figure is the ratio of horizontal to vertical
        frequencies, and has nothing to do with lines of resolution.
                [credit: larson@snmp.sri.com (Alan Larson)]

        NTSC has 525 horiz. scan lines, but the horizontal res. varies
        from VHS to SVHS to broadcast NTSC....  There are test patterns
        available to determine horiz. res.
                [credit: george@Seri.GOV (George Scott)]

24.     What is CLV, CAV, PCM, digital vs. linear audio tracks, etc.?

        Read Bob Nilands (rjn@hpfcrjn.FC.HP.COM) papers on
        LaserDisc topics.  I have read the following :

        LD Media Care & Repair  Part 1 Revised: 31 Mar 90
                                Part 2 Revised: 28 Jul 90
                                Part 3 Revised: 05 Aug 90
        Intro to Imported LDs   Part:       1 of 3 Revised: 14 Sep 90
                                Part:       2 of 3 Revised: 13 Nov 89
                                Part:       3 of 3 Revised: 13 Nov 89
        Intro to Laser Disc     Revised:  29 Sep 90
        Intro to Surround Sound Part 1 of 2     Revised: 18 Feb 90
                                Part 2          Revised: 06 Sep 90
        Film/video 2-3 pulldown and "white flags" Last Revised: 06 Nov 90
        Looking back: CED       Revised: 14 Dec 90
                (re: Capacitance Electronic Disc system)
        
^L
===============================================================================
VIDEOCASSETTE RECORDING/PLAYING         ([S-]VHS/[ED-]BETA/[Hi-]8MM/0.75"/etc.)
===============================================================================
Glossary - Video Tape Formats
-----------------------------
8mm             Videotape format promoted by Sony and others using 8mm tape.
Beta            Videotape format promoted by Sony, much less prevalent than VHS.
D1 (aka D-1)    Digital tape professional format.
D2 (aka D-2)    Total digital tape professional format.
ED Beta         Extended Definition Beta.  Higher resolution Beta format.
Hi-8            Higher resolution 8mm format using higher quality formula tape.
HiFi            Higher fidelity sound encoding on videotape.  Usually
                implies stereo channels.  Up to 20KHz frequency response.
SuperBeta       Improved Beta.  How???
S-VHS           Super VHS.  Enhanced version of VHS dictating the use of high
                quality tape formulation to store higher bandwidth signal.
                Can only be played in S-VHS decks and VCRs with Quasi-S-VHS
                (aka Modoki) mode.
S-VHS Mark II   Super VHS with digital soundtracks (in addition to
                HiFi and linear track(s)).
VHS             Video Home System.  1/2" tape in cassette. NTSC and PAL
                composite video versions.  Standard promoted by JVC & others.
VHS-C           VHS Compact.  Smaller cassette holding 20 minutes of VHS tape.
                Usually for small camcorders.  Can be played in VHS players
                with an adapter (some VCRs can play VHS-C w/o an adapter).
U-Matic         3/4" cassette professional videotape format.  Dying.
------------------------------
Glossary - Video Tape Time Code Standards
------------------------------
RC              Sony 8mm standard?
SMPTE           Society of Motion Picture and Television 
VITC            Vertical Interval Time Code
-----------------------------

25.     What is the proper way to store video tapes?

        So that the tape is flat (and the weight is not on the edge of
        the tape - or it will warp/buckle) - meaning the cassette
        stored upright.  And not on top of your TV, VCR, oven, car
        dashboard or large
        magnet :-)

26.     Now I am totally confused as to how one should store video tapes....

        One of the smallest sides of the cassette box should be on the
        bottom and the other on the top:

                    +----+
                   / T  /
                  /  O / |
                 /   P/  |
BEST            +----+   |    
                |    |   |     
                | L  |(O)|      
                | A  |   |   OR ...
                | B  |   |         
                | E  |(O)|          +---------------------------+
                | L  |   |         +---------------------------+|
                |    |   |         |                           ||
              / | S  |   +         |                           ||
             /  | I  |  /          |     ( O )     ( O )       ||
            /   | D  | /           |                           ||
           /    | E  |/            |      GHOST - 1990         |/
          /     +----+             +---------------------------+
         /                                
        +--------------------------------------------------------....
        |        Shelf
        +--------------------------------------------------------....

27.     Are head cleaners bad?  What is the best way to clean heads?

        The cheap abrasive tapes and solvents are reputed to be.

        The Scotch cleaner tapes are supposed to be safe.

        Take your unit apart (some units have easier access than others)
        and clean the heads with a professional head cleaning kit or
        take it to a professional for servicing.

28.     What is HiFi sound and how is it recorded on tape?

        HiFi sound (usually found on higher-end consumer VHS VCRs and
        usually stereo) is a wider frequency response signal (to 20KHz)
        - than normal linear VHS audio and MTS - with 
        noise reduction recorded in a magnetic layer under the video
        signal before (or while?) the video signal is recorded.
        Since is is not a separate track from the video track it cannot
        be erased or redubbed without destroying the video track.

        On NTSC Beta decks the HiFi signal is not in a separate layer.
        It fits in the available bandwidth of the video heads.
                [credit: Bob Clements, K1BC, clements@bbn.com]
        ...2 head Beta is equivalent to 4 head VHS. 
                [credit: Richard Shetron <multics@ACM.RPI.EDU>]

29.     "What is the story behind VHS (& the lack of SVHS) LP mode?"

        Before EP (sometimes called SLP) was invented by JVC some
        manufacturers created a mode that was twice the playing time of
        SP.  It was never blessed by JVC (the VHS standards keeper) -
        and they superceded it with EP (which has 3 times the playing
        time of SP).

        Supporting  multiple playing speeds properly dictates
        additional heads.  Therefore 4 head players are better at
        displaying EP mode tapes.  ( 2 head machines use a compromise)
        An additional set of heads would be useful to support LP mode
        in a proficient manner.

        This is why most 4 head machines don't have special effects
        (freeze frame, slo-mo, etc.) in LP mode.

30.     What is the VCR+?

        It is a device that uses the functions your remote controller
        (for cable converter, VCR) supports to simplify VCR
        programming.  Numbers available in some newspaper TV listings
        are codes which entered into it will program a VCR.


31.     "Which VCR should I buy?"

        The answer depends on many factors.  Do you want the best 
        possible or the best price/performance in a particular class?

        I would not recommend BETA to newcomers to the field unless
        you are willing to put up with compatibility problems.
        If you want to go BETA then you know what you are doing
        (and up against).  VHS has won the consumer VCR market,
        even Sony makes VHS & SVHS equipment now and Sony's real path
        for the future is in 8 and Hi-8 mm.

        If you want to play a wide variety of pre-recorded material
        available at your local rental outlet you should purchase
        a VHS or S-VHS VCR.

        If you want to record live, or copy SVHS, Hi-8 videocassettes,
        LaserDiscs and other high quality video sources I would
        recommend S-VHS or Hi-8mm.

        If you want to do both of the above you should get an SVHS
        deck.

        If size and/or portability is an overriding concern get a
        Hi-8mm deck (although they are very scarce and most Hi-8
        camcorders will function as players).

        There are generally 5 tiers of VCRs, find the best price
        and brand within one for your deal:

        1. $150 Lower class: 2 heads, mono audio. Some play only.

        2. $200 Lower middle: HQ w/either 4 head only or 2 Head with HiFi

        3. $300 Middle Class: HQ, 4 heads, HiFi, MTS/SAP, CATV ready.
                (Most popular currently, I can find these for $250
                 sometimes for people - such as PV4060, but for just a
                 few $$$ more often you can get the ....)

        4. $500 Upper Middle Class: Either #3 VHS with digital special
                                effects or #3 in SVHS.

        5. $750 Upper Class: SVHS, 5+ heads, digital special effects.

        6. $X000 Rich:  Professional SVHS & Hi-8 decks for editing.
                
32.     Can you put a hole in VHS tapes to record in SVHS mode on them?

        Yes.  The best way is to melt a hole (drilling leaves particles)
        - look at an SVHS cassette to see where to make the hole.
        Not all tapes produces satisfactory (video) results (high
        quality tapes are better).

33.     How come the RF output from my VCR (one Channel 3/4/X) lacks MTS?

        The tuners in both my VCR and TV have MTS and I am playing a
        HiFi tape....

        It would be  expensive to produce and include RF transmitter
        circuitry (for VHF channel X) that would do decent MTS (using
        IF) (the normal RF baseband unit is cheap).  Converting HiFi to
        MTS will result in a degraded audio quality anyway.  Use your
        stereo (L & R) VCR audio outputs to hear HiFi.  Hook them up to
        your stereo if your TV doesn't have stereo audio inputs.


^L
===============================================================================
LASERDISCS & OTHER VIDEO DISC FORMATS
===============================================================================
Glossary
---------------
CAV             Constant Angular Velocity - storage/access method for a disc
                        media where inside tracks contain the same amount of
                        data as outside tracks.
CD              Compact Disc standard (5" and 3" versions),
                usually refers to a disc with all audio track (70+ minutes).
CD-ROM          Compact Disc - Read Only Media.  5" disc containg digital
                binary data tracks.  Often structured according to ISO 9660
                and/or High Sierra (although the data can also be structured
                as a SunOS Unix File System or Macintosh filesystem, etc.).
CD+G            Compact Disc plus Graphics.  Mixed audio and data tracks.
                I believe the graphics are encoded in the data tracks (probably
                digitally compressed) and are used in some 16 bit game systems.
CDI             Compact Disc Interactive.  Mixed audio and less than full
 (aka CD-I)     frame/motion video system just getting off the ground (Fall 91).
                Competing with CDTV.  Some believe CDI will be able to provide
                VHS quality for 72 minutes with data compression.
CDTV            Commodore Dynamic TeleVision - Another 5" disc format with mixed
                audio, video/graphics and binary data.  Competing with CD-I.
                Currently less than full frame/motion video. Just released,
                primarily for interactive video games and education.
CDV             Compact Disc with Video.  CD format with 5 minutes of Audio and
 (aka CD-V)     Video, 20 minutes of audio-only.  Can be played in standard
                (audio-only) CD players.
CLV             Constant Linear Velocity - storage/access method for a disc
                media where outside tracks contain more data than
                inside tracks (by reading the outside tracks at a slower
                speed almost the complete density of the disc is used).
LaserVision     Licensed trademark for 8" and 12" laser disc standard.
---------------

34.     Is the video on laserdiscs (LDs) digitally encoded?

        No.  This is a popular misconception that the LD manufacturers
        often gloss over.  LD video is analog.  The original LD audio
        tracks were/are analog also, most newer LDs have CD-quality
        digital stereo audio tracks as well.
^L
===============================================================================
AUDIO
===============================================================================
Glossary - Audio
----------------
AM              Amplitude Modulation - analog method of encoding audio
                information (usually for broadcast) by varying the
                amplitude of the signal.
Chace           Licensed process of synthesizing stereo and surround
                channels from audio sources where they didn't exist (by
                separating and directing different frequencies to
                different channels).
DBX             Patented audio noise reduction method by ???.
Dolby(tm)       Trademark and name of laboratory which licenses several audio
 aka [)(]       processing/encoding methods to preserve fidelity and reduce
                noise.
Dolby Surround(tm)      Dolby Labs Trademark and name of its process of 
                phase encoding spatial information using the 2 channels of a
                (normally) stereo sound source.
Dolby Pro-Logic Surround(tm)    Dolby Labs Trademark denoting a process 
                incorporating its standard (or meeting its criteria) for
                decoding Dolby Surround(tm) into 5 channels (& speaker 
                placements): Center (dialog), Left Front, Right Front, 
                Left Rear, Right Rear.
FM              Frequency Modulation - analog method of encoding audio
                        information by varying a (high) frequency carrier.
Q-Sound         Method licensed by ????.  Creates spatial sound
                effects with only 2 speakers (using phase tricks).
                Requires careful listener placement.  One rec.video
                reader reported he bought Madonna's Immaculate
                Collection album set just to hear Q-Sound.
SRS             Sound Retrieval System(tm).  Hughes system for
                creating spatial sound effects with two speakers.
                Incorporated into some newer monitors/televisions.
THX             1) A licensed trademark from Lucasfilm that certifies 
                a that a particular theater meets their standard for
                acoustic quality, audio equipment and speaker placement.
                2) A method of mixing surround sound channels for a
                film, with verification in a THX-certified theater.
                3). A brand for (high-end) consumer audio/video gear
                meeting Lucas specs.
                [credit: Bob Niland     rjn@FC.HP.COM]
^L
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

[Scroll credits....]

Thanks for many answers, suggestions and posting gleanings to :

        Bob Niland rjn@hpfcrjn.FC.HP.COM
        B.King@ee.surrey.ac.uk (Bevis R W King)
        goldberg@dtoa3.dt.navy.mil (Mark Goldberg)
        wlrc@uhura.neoucom.EDU (William R. Cruce)
        brown@vidiot.UUCP (Vidiot)
        (Andrew Klossner   (uunet!tektronix!frip.WV.TEK!andrew)    [UUCP]
                        (andrew%frip.wv.tek.com@relay.cs.net)   [ARPA]
        larson@snmp.sri.com (Alan Larson)
        "Hugh_E._Wells.ElSegundo"@Xerox.COM
        taj@hpcuhc.cup.hp.com (Tom Jack)
        ben@val.com (Ben Thornton)
        scott@blueeyes.kines.uiuc.edu (Scott Coleman)
        David.Weaver@earth.Eng.Sun.COM (David Weaver)
        Seng-Chou Timothy Chou <chou@cs.uiuc.edu>
        Bob Clements, K1BC, clements@bbn.com
        george@Seri.GOV (George Scott)
        Richard Shetron <multics@ACM.RPI.EDU>
        schuster@cup.portal.com (Michael Alan Schuster)
        gpinzone@george.poly.edu (A1 gerard pinzone (ee))
        dfh@dwx3bs.att.com (Dave Haertig)
        "Frank J. Wancho"       WANCHO@WSMR-SIMTEL20.ARMY.MIL
        John Mc jmclachlan@draper.com
        zhu@wobbegong.cs.indiana.edu (Zheng Zhu)
        jfr@locus.com (Jon Rosen)
        ingram@hotair.enet.dec.com (Larry J. Ingram)
        Nick Sayer <mrapple@quack.sac.ca.us>
        Bill Ranck <RANCK@VTVM1.BITNET>
        bill@bilver.uucp (Bill Vermillion)
        boyajian@ruby.dec.com (Jerry Boyajian)
        kimnach@lims01.lerc.nasa.gov (GREG KIMNACH)
[end credits.... fade to black]
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

                      Copyright 1991 H. Morrow Long

                   All Rights Under Copyright Reserved

                Quoted and derivative material contributed by
                persons other than the above author/editor
                remains their intellectual property.
                      
    Permission is granted for the automatic redistribution of this article,
    unedited, through the Usenet video newsgroups and the Internet
    VIDEOTECH Digest.  Permission is granted for each Usenet reader, each
    VIDEOTECH subscriber and each person who received this article via
    electronic mail from the author to redistribute it electronically, and
    via hardcopy reproductions of this edition of this article for personal
    non-commercial uses, and provided that no material changes are made to the
    article or this copyright statement.  Other uses of this material are
    prohibited without the express written consent of the author/editor,
    H. Morrow Long.

    Disclaimer: Any views expressed here are mine and do not
                necessarily represent those of Yale University.

H. Morrow Long, Mgr of Dev., Yale Univ., Comp Sci Dept, 011 AKW, New Haven, CT
06520-8285,     VOICE:  (203)-432-{1248,1254}           FAX:    (203)-432-0593
INET: Long-Morrow@CS.Yale.EDU UUCP: yale!Long-Morrow BITNET: Long-Morrow@YaleCS
WWW:    http://www.cs.yale.edu/HTML/YALE/CS/HyPlans/long-morrow.html

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
----------------------------end of rec.video FAQL




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