BCD436HP Checking Signal Strength P25 II

Can anyone help out a digital newbie? Is there any way to check the incoming signal strength while trying to aim my 9.95$ yagi? The signal strength display does not vary much from a few bars. I am outside of the user area of the system, and I get the "dat" steady, but the audio seems garbled.

Also, can anyone interpret what the ERR codes mean?



Thanks

Mike

W2MDM