I have been detecting in an old park about 1 block from my house. I use a prizm II and have been very happy with it. I have found a few mercury dimes and barber quarters as well as some wheat pennies and buffalo nickels. The park was established in approx. 1895 and was closed around 1970. The nice thing about this is that almost everything found is old (coins). I'm having trouble getting a repeating signal from alot of the coins that i am finding. I get maybe 1 or 2 signals and then nothing. I have been lucky to dig some of the signals and find some coins. Today i found a 1944 mercury dime and a 1920 libery half dollar. I seem to be having trouble getting a repeating signal and i'm wondering is the prizm II is not going deep enough. What might be a good detector for getting deeper than the prizm? Any suggestions would be helpful. Thanks