The system isn't that complicated (assuming that it hasn't changed since I was familiar with it). AFAIK, troopers use both the SP's own system and whatever local systems are available (since 911 centers more and more directly dispatch troopers, a lot different from the good ole days where that would have gone over like a lead brick). The latter (cruisers working local systems) is no different than the radios in other cruisers. The former (SP's own system) isn't really that complex.
SP's own system consists primarily of the VHF lowband patrol channels used by the patrol Troops 1-6. They are half-duplex: base transmits on one freq (almost [?] always the lower of the pair), and mobiles transmit on the other, with no automatic repeating (i.e., so you have to listen to both). Because of our beautiful terrain, SP detachments that dispatch are linked to the patrol channels through assorted mountain tops by remote bases (as I described in my previous email, on VHF midband and UHF).
Many cruisers also (at least used to) have mobile repeaters, using VHF highband simplex channels to repeat back through the cruiser's lowband radio. And along with the mobile repeater frequencies, there are also a handful of car-to-car VHF highband channels.
Troop 7 (Turnpike) uses a VHF highband repeater. It used to have (I think) two slaved transmitters on the same frequency -- 155.430 -- that were linked with some combination of wire and 900 MHz links (there were places where you could hear the 155.43 transmitters phase beat with together... neat effect.. weeeooooeeeooowwooowww). That freq is also used as a talkaround channel, when it's called "DIRECT." Tamarack has a UHF repeater linked (one-way, I think) to Troop 7 F-1 (I suspect so that the Tamarack folks can listen to the Turnpike repeater on their UHF HTs). T7 also used to use UHF mobile repeaters, and the Turnpike Authority had a pair of VHF high simplex channels, although I haven't heard anybody on them for ages.
[<funnystory> .. I was told at a meeting once by a Moto rep who will remain nameless that Troop 7 started to put a second repeater system on the air. It was intended to be [I think] 3 repeaters that were SecureNet protected. He told me that the funding dried up, though, so the system was never implemented. But I told him that one of the repeaters [the one in Charleston] _was_ on the air (it can be keyed up). His -- surprised -- response was that he thinks nobody knows this. I told him I had NEVER heard anyone on it, although I listen to it regularly. Plus, its input is adjacent to the output of Raleigh County SO 1, so whenever RCSO switches to SecureNet, the Turnpike's "phantom" repeater will sporadically key up. I bet if you used that repeater, _nobody_ would ever hear you. If he got this right, it says a lot about Moto equipment... been up for years and nobody even knows about it.
And that reminds me of another funny story related to another thread here. One time ages ago, I went with an OES tech to work on one of the IFLOWS voice transmitters that the 911 center reported hadn't been working for some number of months or years. We pulled the transmitter away from the wall and discovered that somehow the audio/mic wire, which was made with 2-pair telco wire, had become stripped and twisted, so that all four circuits were shorted together. That transmitter had been on the air {and still was when I got there} for almost a YEAR without missing a beat! Go, Moto! </funnystory>]
Troop 8 (BCI) also uses a system of standalone VHF highband repeaters and a number of tactical simplex channels. AFAIK, the detachments also have radios on the BCI repeaters, as I hear the BCI guys talking with each other and the detachments occasionally.
The Executive Protection Troop has its own VHF highband repeater at the Governor's Mansion, and also a handful of tactical simplex channels.
What am I forgetting?? I hope this is all correct; if it's not, I hope someone who actually knows will correct me. Finally, this is all subject to eventual change given the State's plans to migrate to P25 UHF.
...R