RFO and response filed, initial hearing this Monday, no marriage no prior orders. Mother is limiting contact anything I can do?

You would have to make your argument(s) in court that the opposing party is limiting contact with your son (and describe how the opposing party is doing that). In addition, you would have to argue about what is in the best interest(s) of your son. Ultimately, at the end of the day, the court will make its ruling based upon what is in the best interest(s) of your son.

You deal with it in court Monday. You deal with it by asking the court to Order a specific time for calls, and depending on the age of the child that Mom is not in room or on other line. You can request the Judge to Order Skype calls if he has computer access as the kids enjoy seeing the parent. Alternatively you can ask the Judge to Order that you can buy kid cell phone for his personal use to call or text you anytime without Mom's supervision or interference. Just make sure the phone is set up with parental restrictions so he can't get on adult sites. I always recommend just before bedtime as the kids are settled down, done with homework and dinner. Mom will most likely suggest a time that won't work so explain to the Judge bedtime is better for reasons stated. I suggest for younger kids to read a story after you gab, have the child get the same book from the school or local library so they can read along. The Judges like this and most parents find at bedtime the kids are less distracted and more willing to talk. This is a court Order, Mom must comply or face consequences. For the next hearing, and it will probably be continued,, file your documentation by filing a Declaration, CA Judicial Council Form MC-030 in which you make a statement about your evidence based on your personal knowledge and attach your evidence to the Declaration. A good example and directions is at http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=FAM&sectionNum=7822.