VHS videotapes are somewhat delicate, and video cassette recorders are complex mechanical devices. To play the tape they extract it from the cassette and wrap it around a rapidly rotating head. No wonder a tape occasionally gets jammed. First you need to get the tape out of the machine, then you need to make it playable again.
Sometimes there’s only a small loop of tape stuck in the machine, which can be gently teased out. More likely the tape is wrapped around part of the mechanism and you’ll need to remove the faceplate or top cover of the switched-off VCR to get to the tape. This will probably involve a combination of unscrewing some screws and pressing some plastic parts in the right places to make them “unclip”.
If at all possible, don’t touch the tape because finger oils will lead to later decay of the tape. Clean cotton gloves would be ideal. You will be discarding any crumpled or tangled parts of the tape, so you can handle those while extracting the tape from the machine. Once it is all removed, reassemble your machine.
Now you must choose between attempting a repair yourself, or having the repair done professionally. Professionals naturally recommend using a professional repair service, and warn that a poor repair can easily damage the rotating head on your VCR, making it unusable.
The general idea behind the repair is to cut out the damaged pieces of tape and join the free ends together, before carefully winding the loop of tape back into the cassette. If you attempt the repair yourself, you can use a tape splicer kit (which should come with gloves, screwdriver, splicing tape and instructions) or you can splice it yourself with sticky tape (scotch tape or sellotape).
The risk is that the stickiness from the tape will ooze onto the VCR heads, damaging them, so this repair technique can at best be considered for single use only, e.g. to enable you to transfer the contents of the tape to DVD.
If you are splicing it yourself, a more complicated but safer technique is to transfer one half of the now-cut tape into an empty cassette case (obtained by discarding the tape from a no-longer-needed VCR). This technique has the advantage that the splicing tape connects the tape directly to the cassette hubs, and the sticky tape is not drawn past the VCR heads. You will end up with two cassettes, each of which contains part of your tape. You should immediately transfer these to DVD.
If you would prefer to have your tape recovered commercially, there are many businesses that offer this service. Most of them operate on a “pay only if it can be fixed” basis, but claim that the vast majority of tapes are fixable (although of course you will lose any content that was on the chewed-up piece). Here are services from the USA and the UK, although we are unable to vouch for them and there are many others.
Note that it is not possible to recover the previous content from any part of a tape which has been recorded over.
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