I do not think that all the MSP barracks are encrypted on FiRST. I know for a fact that MSP-I (Easton) is not encrypted on their regular dispatch channel. Tac channels may or may not be encrypted.All of the Frederick City police are encrypted so you cannot listen to them. I do not find much traffic on Maryland State Police Barracks B. I believe all other barracks are encrypted on Phase 2 FIRST system. I am using a small dedicated computer running Linux with software to decode. You could use a Windows machine to decode Phase 1 however. Depending on your computer technical level you could try that route. From what I have read most scanners do a poor job of decoding P25 simulcast systems like we have in Frederick County. The computer/software solution does a good job of it. There is a forum here for Software Defined Radio that has more info.
Maryland has a statewide system called 'FIRST' which is Phase 2, but it is not at all active in Frederick. But that could change in the next year or two.
All Barrack Dispatch Channels are in the clear. Each Barrack has a Tac Channel and CID Channel. All Barrack Tac and CID Channels statewide are encrypted. There are various other MSP tac channels, special ops, etc. are both in the clear and encrypted.I do not think that all the MSP barracks are encrypted on FiRST. I know for a fact that MSP-I (Easton) is not encrypted on their regular dispatch channel. Tac channels may or may not be encrypted.
On the flip side of the encryption coin, most of MD DNR traffic is encrypted.