Frogman,
Now I remember a similar experience with a three-pin Decca which belonged to a friend. At first it sounded fine, in fact quieter than mine. But it suddenly developed this loud buzzing which I couldn't get rid of. Since it didn't belong to me, I simply disconnected it and went back to my own Decca. I never did find out what was wrong with it, but I have heard that the armature of older Deccas can rust: they do eventually die. I hope this isn't the case with yours, but if after all of the previous experiments it still buzzes, then slide the cover back and see what you can see. If it's toast, then I'd try something desperate like opening it and pouring an anti-rust agent in it, or something like that. Ken Kessler of HiFi News is probably the world's leading expert on Deccas, maybe you could e-mail him. Or ask London/Decca themselves, I think a refurbishment is much cheaper than buying new. Is it worth all the trouble? I think so, but mine is now working perfectly, and my previous one, which I foolishly sold, also worked very well. The problem with Deccas is that once you hear one working well, you never forget. Good Luck! Let me know how it goes.
Now I remember a similar experience with a three-pin Decca which belonged to a friend. At first it sounded fine, in fact quieter than mine. But it suddenly developed this loud buzzing which I couldn't get rid of. Since it didn't belong to me, I simply disconnected it and went back to my own Decca. I never did find out what was wrong with it, but I have heard that the armature of older Deccas can rust: they do eventually die. I hope this isn't the case with yours, but if after all of the previous experiments it still buzzes, then slide the cover back and see what you can see. If it's toast, then I'd try something desperate like opening it and pouring an anti-rust agent in it, or something like that. Ken Kessler of HiFi News is probably the world's leading expert on Deccas, maybe you could e-mail him. Or ask London/Decca themselves, I think a refurbishment is much cheaper than buying new. Is it worth all the trouble? I think so, but mine is now working perfectly, and my previous one, which I foolishly sold, also worked very well. The problem with Deccas is that once you hear one working well, you never forget. Good Luck! Let me know how it goes.