Vintage VHS Camera recording issue

Discussion in 'General Electronics Chat' started by Robin Mitchell, Oct 1, 2016.

  1. Robin Mitchell

    Thread Starter Well-Known Member

    Oct 25, 2009
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    Hi All,

    This will be hard to describe but I will do my best.

    I have an old Panasonic VHS camcorder that records to standard VHS tapes (not the mini ones). When the camera is not recording I can see the image that the camera picks up on the little viewfinder. When I go into record mode the image becomes 4 thick grey bars.

    Audio records fine, the recording head is clean and all caspins are clean too.
    I have noticed that when any of the motors on the VHS system start to operate the image has random lines going across, almost like it is interference.

    What would be my best approach?
    I have a feeling that some filter caps may have gone bad but has anyone here seen this before?
     
  2. wayneh

    Expert

    Sep 9, 2010
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    No idea how to help, but to be clear, does the camera record properly, with the problem only being the display while recording?
     
  3. Robin Mitchell

    Thread Starter Well-Known Member

    Oct 25, 2009
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    Nope, the viewfinder is accurate and the recordings are wrong. Audio is fine but the video is wrong. It is strange because when the system is not recording the image from the camera is fine except for random horizontal lines. As soon as the head begins to record the video feed goes into 4 or 5 thick blocks with some colouration.

    When motors are operating the camera feed shows more "interference" lines
     
  4. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    Can you play a pre recorded video in the camera ok, it maybe the video heads?
     
  5. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    The big cylinder that the tape gets pulled across are not spinning correctly. Make sure it turns. The bearings on these old things are actually bushings made of oil-impregnated sintered powdered brass. The oil dries out over the years and just the additives are left. Resetting the additives with oil is a quest that requires much luck. It usually doesn't work. Even efforts to soak them or wash them out with solvent doesn't work.

    Good luck.
     
  6. Robin Mitchell

    Thread Starter Well-Known Member

    Oct 25, 2009
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    Im going to get some photos of the issue today.

    I doubt it has anything to do with the head because the viewfinder probably takes the feed directly from the camera when its recording. The viewfinder shows the large bars, the playback shows the bars and when I play the VHS on a TV it shows exactly the same. It could only be the head if the camera took footage from the head during the record which seems unlikely.

    For the time being (since I do not have any VHS tapes with some normal footage), assume that the heads are fine and it can playback a VHS (such as a movie).
     
  7. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    The only way to break it down for fault finding, is first establish the heads play a normal pre recorded video that was recorded in another video,

    then if that's ok you're looking at the recording section, so you will need a circuit diagram for that.
     
  8. MrAl

    Well-Known Member

    Jun 17, 2014
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    Hi there,

    Just a little future history note here...

    The very last VHS VCR machine was made about a week or two ago by a company in Japan.
    From what i understand, there will be no more VCR's made anywhere in the world now.
    How many are left in the world unsold as of today 10/02/2016 i dont know.
    How many tapes are left unsold i also dont know.
     
  9. Robin Mitchell

    Thread Starter Well-Known Member

    Oct 25, 2009
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    @Dodgydave thanks for your input, I will try and track down a working tape :)

    One thing I will say, I am convinced that it's a power line issue. When any motor is operating lines appear that match the sound of the motor. When the drum spins there are many thin lines, when eject works there are bigger chunky lines, when the tape goes forward or backward more line appear. My guess so far is that either there is a fault with some power regulation or some bypass caps may not be functioning.
     
  10. bertus

    Administrator

    Apr 5, 2008
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  11. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    These cameras came out at about the same time smd electrolytic caps were introduced. Camera owners would generally buy a new camera if theirs didn't work in the late 80s /early 90s - mostly because few vhs repairmen existed. The few that were repaired seemed to be electrolytic caps (SMDs).

    Now, since your problem appears to be the camera CCD. So, replace the caps on the CCD board. Any power fluctuations will feed right through if the caps across the power are bad and issues occurs when the load changes.

    While I had it open, I would change the caps at the power in for the whole camer as well.
     
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