I have a later model 51SL, 4.14.5 firmware, 700/800mhz. I was all setup for my area systems which consist of a 800mhz system and 700mhz system, both P25 trunked. I successfully programmed these systems with correct WACN and system id's and was able to monitor them (without affiliation ofcourse). Anyway, all was fine for a while until I noticed the 700mhz system not receiving. 800mhz is working just fine. I double checked the control freqs and they are good. I decided to program in a control channel directly and see if I could hear the distinct sounds that a control channel should make and I hear just plain static. If I program that same control channel to monitor directly in my scanner, I can hear the scratchy control signals. Its like i'm just not receiving 700mhz. I tried a different antenna, no change. I talked to a tech at EFJohnson, he thought my logic board could have went bad??? Just like that? Anyone have any other ideas? Does the RF deck contain the logic board and if so, anyone have an RF deck for sale?