This can be a problem with the record circuitry, or with one of the
heads. You would have to have a way to follow through the signal path
using a scope, and see where the signal loss is occuring. This would
require a scope, service manual (unless you are very familiar with the
design), and the knowledge of about how the VCR design functions.

Considering that a very good VCR can be bought at a reasonable price,
and that your model is fairly old, I would consider a new machine.
Jerry G.
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