Tip & How-To about Televison & Video

How a VCR and Videotape Work and the Most Common Problems

A common complaint about videotape is that over time, playback becomes unstable and often deteriorates to the point that the tape becomes unplayable or that the tape works on one VCR, but not another. All of these problems can be traced to tape path alignment in the VCR and damage to the tape itself. I will address each issue separately.
First you need to understand a little about the tape media. When you record on VHS videotape, the recorder lays down three (four for stereo sound) magnetic tracks on the ½ inch wide tape. Analog audio is recorded along the top edge as a thin horizontal stripe (or parallel stripes for stereo) for the entire length of the recording. In the center of the tape, video is recorded as diagonal parallel stripes by two or four heads that rotate on a drum at 360 RPM. On the bottom edge (the most vulnerable place for damage to occur) there is another horizontal track that is critical to playback. It is the sync track and it's purpose is provide the VCR with the feedback it requires to maintain the tape speed within extremely tight parameters. If the tape does not move at a precise speed, the picture and sound can become unstable to the point that it will be unusable.
As you record, a fixed frequency sine wave is recorded on the sync track. If during recording, the tape speed increases or decreases, it will be reflected on the sync track. During playback, the VCR's circuitry senses the small millisecond-to-millisecond speed fluctuations of the tape movement over the heads and adjusts the speed so the tape speed always matches the speed at which it was recorded. If the sync track is ever damaged, your tape can become useless.
Unfortunately, videotape is a very delicate media. It is easily damaged and once damaged, it usually cannot be repaired. The most common failure is due to tape stretch. Videotape is not very elastic. Anything more then slight tension during use can stretch the tape to the point that it cannot rebound. If the sync track is stretched, the recorded frequency will change and the VCR will react accordingly by making incorrect speed corrections resulting in picture and sound disruptions. Your recorder has tensioning arms that control tape tension as it moves through the system. If the tension in the tape path is incorrectly adjusted, the tape will be damaged as it is recorded or played.
Improper storage is the other common cause of edge damage. If you lay your cassettes flat for prolonged periods, the weight of the tape above will press against the sync track and can damage it. Always store your tapes vertically. Extremes in temperature and humidity can cause stretch. Store tapes in a cool dry place. Also, periodically restack your tapes. To restack a tape, put it in your recorder and fast-forward it to the end and back to the beginning. That will redistribute the tension on the tape. After playing a tape, always restack it once or twice. I have a large collection; over 1,000 tapes. I cannot restack them all on a regular basis. But when I play them, I take that as an opportunity to restack them.
Now that you understand some basics about the media, I will now turn you attention to your VCR. As I hope you are starting to understand, proper playback requires precise alignment of many moving elements. The two broad categories are tape path alignment and head alignment. None of this is a do it yourself job. In addition to specialized electronic test equipment, VCR alignment requires specialized tools along with expensive custom made for the brand and model alignment jigs along with (again expensive) alignment tapes. The alignment tape is important beyond the obvious. In order for a tape recorded on one machine to play properly on another, the two machines must have matching alignment. VCR manufacturers record their own alignment tapes using precisely and frequently aligned recorders. The tapes are used to align a specified number of VCRs and then discarded because each time a tape is used it wares. Since there is a uniform standard for these tapes, a tape recorded on one brand of VCR should play on another. That is the theory.
Now for the real world; the consistent interchangeability we all wish for is hard to maintain. Consider this. The tolerances that must be maintained at every point in all of the processes relative to VCRs and tapes are very close to what is possible; little room for slight variations. Since the tolerance for one part of the process may accumulate with another part of the process either mathematically positively or negatively, it is often the case that each individual part of the chain is within tolerance, but the sum total is out of tolerance.
What in plane language does this all mean? Two alignment tapes made on the same machine will be different. Tapes from different manufactures will be different. The tape you local technician or factory service center uses will have inconsistencies. The net effect is that two seemingly properly aligned machines may not be able to properly play each other's tapes.
I do not mean to suggest that you should not have your VCR properly aligned and maintained by a professional. My point is that videotape is an old technology with flaws that could not fully be overcome in the time frame that it would have been profitable for manufacturers to do so. That is why we have moved on to digital technologies. My advice is to enjoy your videotapes while you can. They will not last forever. If you have important tapes, transfer them to digital media to protect your memories as soon as possible.

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Using a Sylvania DVR90VF, how can I record from a VHS tape to a DVD?


OK here's what the user manual has to say on it!
PS If you need the user manual I will E-Mail on request.

Prepare for the recording on the DVDRW/ R disc or the videotape. Make sure:• Insert a recordable disc and a videotape with a record tab.
Note for recording to a disc:
• Make sure that the disc is recordable.
1
Hit [SETUP].
Easy Setting Menu or Advanced Setting Menu will appear. If Advanced Setting Menu is displayed,
proceed to step 3.
2
Using [
K / L], select “Advanced Setting Menu”.
Hit [ENTER].
Advanced Setting Menu will appear.
3
Using [
K / L], select “Recording”. Hit [ENTER].
Recording menu will appear.
4
Using [
K / L], select “Dubbing Mode”. Hit
[ENTER].
Option window will appear.
Recording
Auto Chapter 10 minutes
Timer Programming
DVD-RW Recording Format Video mode
Auto Finalize
Dubbing Mode VCR DVD
VCR DVD
Recording
Auto Chapter 10 minutes
Timer Programming
DVD-RW Recording Format Video mode
Auto Finalize
Dubbing Mode VCR DVD
DVD
VCR
DVD-RW DVD-R
VR
DVD-RW
Video
Note
For VCR to DVD duplication:
• After starting VCR to DVD duplication, the picture may be distorted because of the auto tracking function. This is not a malfunction.
5
Using [
K / L], select “VCR DVD”. Hit [ENTER].
6
Hit [SETUP] to exit.
Make sure to select a recording speed using [REC SPEED].
7
Hit [PLAY
B].Then hit [PAUSE F] at the point you
wish to start recording.
• Since it takes about a few seconds before the actual dubbing begins, please allow extra 5 seconds
when selecting the starting point.
8
Hit [DUBBING].
VCR to DVD duplication will start.
9
Hit [STOP
C] to stop the
recording.
When you turn off the unit after setting the Dubbing Mode to DVD VCR, the setting will be set to VCR DVD automatically.
• Dubbing Mode is available only if the videotape or disc is not copy protected.
• You cannot change the output mode during VCR to DVD or DVD to VCR duplication.

For VCR to DVD duplication:
• The playback sound mode is followed by the setting of VCR playback sound mode on page 77. Set the playback sound mode to which you wish to record to the DVD.

May 12, 2010 | Televison & Video

1 Answer

The VHS ate a tape, no power,wont eject, can't get it to work.


Are you asking how to get the tape back? Partial disassembly of the case (UNPLUGGED) would allow removal of the tape.
If you are asking how to repair a VCR, no one can tell you how to do that on a forum. VCRs have quite a number of moving parts, mostly driven by rubber belts. These stretch with time and the mechanisms quit working. Since a simple belt replacement costs as much as a cheap DVD player most people change to DVD at this point.
If you have high-personal-value videotapes (home movies) , these can be converted to DVDs by any local photo service and would last a long time in the new format. They will NOT copy commecial videotapes for you.

Jan 02, 2010 | Toshiba MW27F51 27 in. TV/VCR/DVD Combo

2 Answers

Rolling of picture


Hi,
You camera is PAL and you are attaching with Ntsc TV or VCR. Both Pal and Ntsc are different systems and incompatible to each other.
If you want to see correct playback of your Camera, it requires Pal or Multi-System color TV.
Need further info, please let me know.

Oct 04, 2008 | Sony Handycam CCD-TRV68 Camcorder

2 Answers

ERROR CODES E24 ~& E4 54037380 ON MY DVD RECORDER, CAN ANYONE TELL ME WHAT THESE MEAN, THANKS


If you are trying to record vhs tapes to the dvr side, first you need to get 1x up to 8x DVD-R dvds. You can find them on ebay. The machine has problems recognizing the up to 16x type. Put the blank DVD in and let it load. Then start playing (not dubbing but playing) the videotape for at least 6-8 seconds. If you have somewhat of a lead-in on the videotape you can let it go even 10 seconds. Only after the videotape has been playing for this period of time, press the dubbing button. If the error code does come up, rewind the tape and start again, but in most cases the error code will not happen if you do it like this.

Mar 31, 2008 | Sylvania SRD3900 DVD Player/VCR

1 Answer

Remove tape error message


  1. Condensation is detected – If condensation is detected by the camcorder, the “Remove the Cassette” warning may occur.
  2. Component failure – If an electrical or mechanical component in the camcorder fails, the safety mode may activate to prevent any further damage to the camcorder.
  3. Sand or grit damage – The camcorder’s tape drive mechanism consists of many tiny gears. Sand or grit can cause a gear to jam and stop turning. This will cause the camcorder's safety mode to activate.
  4. Impact damage – If a camcorder is accidentally dropped or bumped against a hard surface, it is possible that a misalignment of the tape drive mechanism may occur.
  5. Liquid damage – If either the camcorder or the tape is exposed to water or any other liquid, a variety of malfunctions may result. Please avoid this situation.
  6. Improper videotape insertion – If a tape is forced into the cassette compartment, or if the cassette compartment is pressed down while the tape is loading, damage may occur to the tape drive mechanism. Please refer to the User's Manual.
  7. Damaged or defective tape – If a tape becomes damaged, please discontinue its use.
Operational Recovery Steps
Depending on the conditions that caused this message to appear, it is possible that the camcorder operation may recover. Please follow these steps:
  1. Eject the videotape
    Insert a new or known good videotape. If the message does not persist, it is possible that the tape was damaged. If the camcorder still displays the message with a new tape, please proceed to step 2.
  2. If condensation had been detected causing the Remove the Cassette warning, remove the cassette, and allow at least one hour for the moisture to dry.

Nov 19, 2007 | Canon Elura 100 Mini DV Digital Camcorder

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