Philips VR948

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The Philips VR948 is a VCR (Video/VHS Tape/Casette Recorder). Most of the problems and solutions here will be the same for many other VHS players. You will probably be able to find a lot of information about these on the internet, but there are a lot of home-remedies out there that don't really solve the problem or destroy the hardware.

The internal electronics and the moving parts are very much alike the Grundig GV 440 (might help you find information and service manuals). A link to a service manual for the VR984: [1]

Reasons for repairing and quick references[edit | edit source]

You might not want to repair this to put it back in your living room, because magnetic tapes are very fragile and are not very well suited for frequent playing. However it is essential to be able to repair these devices as new devices are becoming very scarce, but a lot of people still have a lot of memories on them. You can digitize these easily using an analogue (CVBS/Composite, Component or S-Video and analogue audio) capture card off ebay. Easy way: on windows, mac and linux you could use OBS screen recorder in lossless mode. A guide for how to capture lossless video and audio on linux for more control: [2]. Or if you really know what you are doing, it is even possible to read out the raw signals of the video and audio heads with an analogue-digital converter and decode them in software (using vhs-decode (forked from ld-decode): [3]), meaning you can make near-perfect copies without all the processing done by the tape recorders aging electronics.

When an internet source is quoted (starting with: "On the internet it is said"), nobody working on this article has actually successfully tried the solution and it should be taken with a grain of salt. These are here for reference purposes.

Known problems and solutions[edit | edit source]

Problem Solution
  • Only a snowy image or a partly video and partly snowy image. This might improve after running a tape for a while, but come back after stopping the playback and restarting.
  • Sound is fine
  • This is the case with any tape you try
  • This is often because of dirty video heads (the tiny black slits (with tiny inductors) on the bottom of the rotating part of the video drum). These should NOT be cleaned with a Q-tip, because the cotton can get stuck in there and that will be very hard to remove without damaging the fragile heads. The drum and the heads can be cleaned with a piece of paper dipped in a pure alcohol (like isopropyl alcohol), Don't use a solution or unpure alcohol as the residue that will leave behind can make the heads dirty or even erode them. See Picture [4] 2 are the tape heads.
  • Player "eats" Tapes (What you see is a tape that gets stuck in the player and when ejecting it wrinkles the tape). That part of the tape might not be salvageable anymore, but the rest of the tape is probably still fine. A very good video: [5]. If it is really bad, you can try something like this: [6].
  • Do NOT try another tape; The same thing will happen. A common cause for this is a cracked pinch roller. See Picture: [7]. The pinch roller has a rubber part that often dries up (also happens in Audio Cassette Decks). The Rubber might get cracks in it, where the tape can get stuck. The best fix would be to replace the pinch roller entirely, but good luck finding that part at a fair price or at all.
  • This fix is not recommended way to fix it (the Jumping image problem might occur when doing it wrong), but if you have nothing to lose: It might be worthwhile to cut away the rubber. If there is erosion on the metal part, sand it. Then use very high shrink ratio polyolefine shrink wrap. for this particular roller use: 1:4 24mm. And shrink it around the metal part. The middle might bulge a little, but that might not cause a problem. This material acts kind of the same as the rubber and, if it has the right thickness, the pressure of the roller should make sure that the tape goes at the right speed. The roller should be pressed against the capstan by a strong spring, not the mechanism. Example of the kapstan (left) and the roller (right) on an audio casette player: [8] (Note that the pinch roller is degraded and might start "eating" tapes). Put in some oil in the ball-bearings, while you're at it and slide it back.
  • Image jumps up and down the screen.
  • This might be because the tape speed changes quickly, which is often caused by a degraded pinch-roller. The pinch roller is probably not cracked yet in this case, otherwise you might not be able to eject the tape without the player "eating" it. The pinch-roller might be shrunk on one side of the roller. The solutions to the Tape eating problem will solve this.
  • On the internet it is said that this can be fixed with rubber-renew. Source:[9]
  • Not starting at all
  • Not starting immediately, but after a while
  • This is pretty specific to the power supply in the VR948. This might be because of a bad PSU. The part combination in the PSU that can break and cause these symptoms: TDA-4606-3, CNY17(-f) (in some models the equivalent part: K1150PG), TL431C, 56uF/35V Elco, MP3-X2 68N. If you keep using it regardless of these symptoms the RFI-Capacitor might break and start emitting smoke. Replacing these and maybe also the 47uF/400V and MP3-X2 100N should solve the problem.
  • A single tape can't start playing (when opening the device and putting in the VHS tape, you see the mechanism trying to grab the tape-lint, but it can't take it out (all the way and definitely can't start playing it))
  • This can be because of something called sticky shed syndrome and it means that that particular tape was made with a material that reacted with water or was stored in a very humid place, which makes the tap stick to itself and the other moving parts. On the internet it is said that this can be solved by baking the VHS tape on a low temperature for some time to allow the water to reverse the binding of water atoms. However heat will definitely degrade the magnetic information on the tape and therefor the image and audio quality will suffer. Source: [10]
  • A single tape won't show a clear image (snow) on the player (other tapes after it might also not play well anymore).
  • That particular tape might be dirty. This will be bad for the heads and after such a tape was played and the image quality of other tapes suffers, the solution to the snowy image problem might solve the problem. Trying the same tape again is NOT recommended.
  • This might have the same cause as the single tape not playing problem and might be solved by the same solution.
  • It can be dirty because of mold, in this case the tape is probably not salvageable and trying to play it, can damage the player. However if the data on the tape is more important than the VHS player: On the internet it is said that the tape can be cleaned by putting cloth against it when fast-forwarding and after that removing the rest. [11]. However the tape might get damaged (nothing to lose there), but the VHS player might get damaged because of the mold. Also: live or dead mold always excretes (sometimes invisible) spores that are sometimes very poisonous. This can make you very sick and therefor proper safety precautions should be taken. At least use a good air-particle/dust filter mask (On the internet it is said that N95 is recommended [12]) and try doing this outside with no people around to protect those around you.