Nmsp
Hello,
It seems my fellow New Mexicans have gotten shy. I live in Santa Fe, so all I can speak about it how the State Police operates in the Northern part of the State.
At one time there were 14 Districts covering New Mexico. Up here, the State Police call signs are the numbers you see on the cars and on their license plates. For example, if the SP car you see has the number 323 on it, then normally that is the call sign you will hear from dispatch. In NM we dispatch sort of back wards. Instead of Unit 323 Santa Fe, you will here Santa Fe Unit 323. The SP generally follow the APCO 10 codes but do have some variation to the codes. I hope that helps. Like I said, I don't know if they dispatch differently down south.
Tim/icemantim8