Well, silly as this may seem, there isn't any makers identification (i.e. "JVC" or "Panasonic") it just says "Music Center Hi Fi System". I (obviously) haven't got the manual that came with it. It was a present from my (now) wife.
Thanks to everyone for the advice. I now have to find someone who can take a look at "the Old Girl". It may be difficult with lock-downs etc. Nevertheless, you've all been very helpful.