The Radio Information Board

I am trying to figure out why the pl codes that i have entered are not working. is there a special board or chip that is needed?

Nope, it should work if programmed correctly. there some adjustments for tone and balance for PL but you need a scope to do it right. Peter

Do you have the hang-up button on the back of the mic grounded? If not, the radio thinks it is "off-hook", and is in monitor (PLs defeated).

Thanks for the information...I think it has to do with the Off Hook as mentioned...

You can program the tone to ignore the hangup signal.