I bought a Whites Coinmaster 5 Supreme in 1976, depth was fantastic! I must admit from about 1985 to now it's mostly sat on a shelf, I bought fresh batteries and powered it up expecting the kind of depth I remember. It still works, but about half the depth! It has great sentimental value so it isn't going anywhere, even if I have to use it as a paper weight, but I'd rather be digging coins. I'd appreciate any advice.