So 172.375 and 164.9375 aren't digital correct?
I can hear those.
Correct.
Use 151.430 to listen to Fish and Game. I don't know if you have taken advantage of the database on this site. It lists frequencies by agency and whether they are on a trunked system and what type of modulation is used be it digital, AM or FM.
You will also find a list of the frequencies used by the San Bernardino, Cleveland and Los Padres National Forests. Listening to State Parks can be interesting too. They use 800 MHz frequencies and are not trunked or digital. They are harder to hear depending on your location due to the more limited distance that 800 MHz signals travel. The L.A. County Fire Department responds to structure fires, medical incidents and traffic accidents on the Angeles NF. The L.A. Sheriff's Department responds with large helicopters to many of those accidents, many of which occur on the Crest Highway and involve motorcycles.
The Angeles is the most difficult National Forest in the country from a people management standpoint. San Gabriel Canyon tops the list of the most difficult areas to manage. From a fire management perspective it is one of the most dangerous National Forest. There is a lot of action on the Angeles.
This is a great hobby. For most of us the more we listen the more we want to hear. We like figuring out the procedures agencies use, their unit designator systems (some call them call signs), lingo and terms, and their channels plans. This website is the best on the internet for finding those things out. Take some time and explore the various forums. Spend time exploring the database. Make sure to click on the wiki page for each each database page as you will often find useful information. Read the forums and ask questions. There are a lot of people who like to help beginners. There are no stupid questions here, we all started from the same place you are. Many topics that are not covered in the geographically specific area forums are discussed in the general scanning forum. Here you can ask questions and read about how to use radios and ask questions that pertain to public safety agencies, utility companies and businesses.
Welcome to the hobby!